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A nitrogen-doped nanocrystalline electrochemical graphite sensor for the sensitive determination of oleuropein (OL) from extra virgin olive oils (EVOOs) is presented. The sensor was developed by the deposition of nanocrystalline graphite (NCG) using plasma-enhanced chemical vapour deposition (PECVD) on silicon wafers. Scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and X-ray diffraction analysis (XRD) were used to characterise the microstructure and morphology of the developed materials. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SWV) were used to investigate the electrochemical properties of the material and the performance of the sensor. The developed sensor showed good analytical performance against OL over a concentration range of 5.00-500.00 mu M, with a good detection limit of 3.93 mu M and a good sensitivity of 0.057 mu A mu M-1. The reproducibility of the electrochemical sensor was excellent, with a relative standard deviation (RSD) of 8.56% for seven measurements.

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The present study evaluated three green extraction methods, accelerated solvent extraction (ASE), ultrasound-assisted extraction (UAE), and laser irradiation extraction (LE), for the polyphenolic compounds and vitamin C extraction of Cornus mas L. and Crataegus monogyna fruit extracts. The polyphenols and vitamin C of extracts were quantified using HPLC-DAD, and the total phenolic content, flavonoid content, antioxidant activity (DPPH and reducing power), and antidiabetic activity were also studied. The antidiabetic activity was examined by the inhibition of alpha-amylase and alpha-glucosidase, and in vitro on a beta TC cell line (beta-TC-6). The results showed significant differentiation in the extraction yield between the methods used, with the ASE and LE presenting the highest values. The C. mas fruit extract obtained by ASE exhibited the best antioxidant activity, reaching an IC50 value of 31.82 +/- 0.10 mu g/mL in the DPPH assay and 33.95 +/- 0.20 mu g/mL in the reducing power assay. The C. mas fruit extracts obtained by ASE and LE also have the highest inhibitory activity on enzymes associated with metabolic disorders: alpha-amylase (IC50 = 0.44 +/- 0.02 mu g/mL for the extract obtained by ASE, and 0.11 +/- 0.01 mu g/mL for the extract obtained by LE at combined wavelengths of 1270 + 1550 nm) and alpha-glucosidase (IC50 of 77.1 +/- 3.1 mu g/mL for the extract obtained by ASE, and 98.2 +/- 4.7 mu g/mL for the extract obtained by LE at combined wavelengths of 1270 + 1550 nm). The evaluation of in vitro antidiabetic activity demonstrated that the treatment with C. mas and C. monogyna fruit extracts obtained using ASE stimulated the insulin secretion of beta-TC-6 cells, both under normal conditions and hyperglycemic conditions, as well. All results suggest that C. mas and C. monogyna fruit extracts are good sources of bioactive molecules with antioxidant and antidiabetic activity.

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A chloroform bulk liquid membrane and Aliquat 336 ionic liquid as a carrier (ligand) were used to remove aspartame (ASP) from an aqueous solution. Experiments were performed in a tube-in-tube setup, under mechanical stirring of inner tube (200 rpm), for 7 h. The inner tube contained a stripping phase (an aqueous solution of HCl) and the outer tube the liquid membrane at the bottom and a feed phase (an aqueous solution of ASP and NaOH) at the top. Maximum extraction, stripping, and recovery efficiencies of ASP of 97.0 %, 75.4 %, and 73.1 % were obtained under the following working conditions: initial concentrations of ASP and NaOH in the feed phase of 10(-4) mol/L and 10(-2) mol/L, respectively, initial concentration of Aliquat 336 ligand in the chloroform membrane of 10(-2) mol/L, and initial concentration of HCl in the stripping phase of 10(-2) mol/L. A characteristic kinetic model of consecutive irreversible first-order reactions was used to predict ASP concentrations in the phases of the membrane system under optimal conditions. The extraction and stripping rate constants (k(1) = 2.48 x 10-4 s(-1) and k(2) = 0.574 x 10-4 s(-1)), i.e., the model parameters determined from experimental data, suggested that the chemical reaction occurring at the interface between the membrane and stripping phase was the rate-limiting step in the mass transfer of ASP.

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We have developed a bienzymatic biosensor that contains acetylcholinesterase together with butyrylcholinesterase co-immobilized on the same electrode modified with a stabilized copper containing Prussian blue electrodeposited on electrodes coated with 4-aminothiophenol monolayer using diazonium chemistry and copper nanoparticles for improved sensitivity. There are organophosphorus and carbamate neurotoxic insecticides that inhibit only one of the two enzymes, e.g., pirimicarb inhibits butyrylcholinesterase at much lower concentrations than acetylcholinesterase while methomyl inhibits only acetylcholinesterase. Our system is simple and in a single measurement provides a sensitive signal for insecticides' presence based on the inhibition of the enzyme with the highest affinity for each toxic compound. The limits of detection are 50 ng/mL pirimicarb for the bienzymatic biosensor in comparison with 400 ng/mL pirimicarb for the acetylcholinesterase biosensor and 6 ng/mL methomyl for the bienzymatic biosensor, while inhibition is obtained for the butyrylcholinesterase biosensor at 700 ng/mL.

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Background: Targeting gut dysbiosis to treat chronic diseases or to alleviate the symptoms is a new direction for medical adjuvant therapies. Recently, postbiotics have received considerable attention as they are non-viable probiotic preparations that confer various health benefits to the host without the safety problems associated with using live microbial cells. Objective: The aim of the study is to obtain selenium (Se) and zinc (Zn) enriched Saccharomyces boulardii postbiotic biomass and to analyze its modulation effect because these minerals play an important role in reducing gut dysbiosis linked to cardiovascular (CV) diseases. Method The effect of the S. boulardii and Se/Zn enriched yeast postbiotics on CV microbial fingerprint was studied in vitro using the gastrointestinal system (GIS 1) and analyzed by microbiological, chemical, and qPCR methods. Result: There was a 2.2 log CFU/mL increase in the total bacterial load after SeZn postbiotic treatment and in the qPCR counts of Firmicutes phyla for both treatments. Beneficial taxa, Bifidobacterium spp. and Lactobacillus spp., as well as Bacteroides spp. were up to 1.5 log higher after mineral-enriched postbiotic application, while the acetic acid level increased. Conclusion: These preliminary studies highlight the therapeutic potential of using Se/Zn enriched yeast postbiotics as adjuvants for clinical treatments of CV diseases.

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Essential oils (EOs) extracted from various medicinal plants offer a promising alternative to non-selective chemical substances commonly employed in conventional agriculture. Their chemical composition includes several classes of chemical compounds with beneficial properties, such as monoterpenes, sesquiterpenes, and phenylpropanoids, which can selectively control microbiological elements in soil and plants. The aim of the present study was to evaluate the essential oils and floral waters obtained from a new variety of marigold (Tagetes patula L., fam. Asteraceae, Nanuk variety) across various parameters, including biochemical characterization using GC-MS, antioxidant activity evaluated under three methods (DPPH, ABTS, FRAP), antimicrobial properties (for three G(-) bacteria: Perctobacterium carotovorum, Pseudomonas marginalis, Pseudomonas syringae and against three phytopathogenic fungi: Rhizoctonia solani, Fusarium oxysporum, Botrytis cinerea), and insecticidal activity. The results showed that when applied in high concentrations, marigold essential oil has a potential bactericidal effect on P. carotovorum, as well as a potential fungicidal effect on B. cinerea.

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Ag nanoparticles (AgNPs) were biosynthesized using sage (Salvia officinalis L.) extract. The obtained nanoparticles were supported on SBA-15 mesoporous silica (S), before and after immobilization of 10% TiO2 (Degussa-P25, STp; commercial rutile, STr; and silica synthesized from Ti butoxide, STb). The formation of AgNPs was confirmed by X-ray diffraction. The plasmon resonance effect, evidenced by UV-Vis spectra, was preserved after immobilization only for the sample supported on STb. The immobilization and dispersion properties of AgNPs on supports were evidenced by TEM microscopy, energy-dispersive X-rays, dynamic light scattering, photoluminescence and FT-IR spectroscopy. The antioxidant activity of the supported samples significantly exceeded that of the sage extract or AgNPs. Antimicrobial tests were carried out, in conditions of darkness and white light, on Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Candida albicans. Higher antimicrobial activity was evident for SAg and STbAg samples. White light increased antibacterial activity in the case of Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa). In the first case, antibacterial activity increased for both supported and unsupported AgNPs, while in the second one, the activity increased only for SAg and STbAg samples. The proposed antibacterial mechanism shows the effect of AgNPs and Ag+ ions on bacteria in dark and light conditions.

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In recent years, various studies have been carried out to increase the concentration of antioxidant active principles in red wines as a consequence of the effects of winemaking techniques on the polyphenols content. In this study, in order to obtain the most optimal wine in terms of content and efficiency of antioxidant activity, various winemaking technologies (punching-down and pumping-over maceration) were tried with diverse gradations (Feteasca Neagra and Cabernet Sauvignon wines) and the addition of different concentrations of melatonin in must. Suitable HPLC and spectrophotometric methods were used to follow the evolution of the antioxidant compounds from wines during aging (for 12 months). After comparing the acquired results, an increase was observed in the antioxidant compound concentrations, particularly in resveratrol (85%), peonidin-3-glucoside (100%) or cyanidin-3-glucoside (100%), and antioxidant activity (10-40%). The most enriched wine was obtained in the case of Feteasca Neagra by the addition of 0.5 mg of melatonin per 1 kg of must using the punch-down technology and, in the case of Cabernet Sauvignon, by the addition of 0.05 mg of melatonin per 1 kg of must using the pumping-over technique. This study can provide winemakers with an approach to enhance red wines with antioxidant compounds.

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This paper aimed to investigate the bioactive compounds in the dry powder residue of honeysuckle cultivars after extracting the juice. Based on the analyses performed on the total content of phenolic compounds, flavonoids, anthocyanins, tannins, carotenoids and vitamin C, the results indicated that dried Lonicera caerulea residue represented a rich source of phenolic compounds (8041.36 mg GAE 100 g(-1)), of which about 80% were tannins (6432.10 mg GAE 100 g(-1)). The flavonoid content varied around 2436.95 mg CE 100 g(-1). Vitamin C (185 mg 100 g(-1)), lycopene and beta-carotene (over 2.5 and 2.8 mg 100 g(-1), respectively) were also quantified. Among the phenolic acids, chlorogenic acid predominated (316 mg 100 g(-1)), followed by cryptochlorogenic acid (135 mg 100 g(-1)) and neochlorogenic acid (32 mg 100 g(-1)). Flavonoids were mainly represented by catechin (2594 mg 100 g(-1)) and anthocyanins (1442 mg 100 g(-1)). Similar amounts of epicatechin and rutin were measured (156 mg 100 g(-1) and 148 mg 100 g(-1)), while the isoquercetin concentration was below 15 mg 100 g(-1). In conclusion, the high level of phytocompounds and the diverse composition of dry Lonicera caerulea residue support its high nutraceutical value and high health-promoting potential.

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The increasing incidence of diabetes has prompted the need for new treatment strategies, including natural products that reduce glycemia values. This work examined the in vitro and in vivo antihyperglycemic effects of new metabiotics derived from Boletus edulis extracts. The metabiotics were obtained from 100% B. edulis, and two other products, CARDIO and GLYCEMIC, from Anoom Laboratories SRL, which contain other microbial species related to B. edulis. Our in vitro investigations (simulations of the microbiota of patients with type 2 diabetes (T2D)) demonstrated that B. edulis extracts modulate the microbiota, normalizing its pattern. The effects were further tested in vivo, employing a mouse model of T2D. The tested extracts decreased glycemia values compared to the control and modulated the microbiota. The metabiotics had positive effects on T2D in vitro and in vivo, suggesting their potential to alleviate diabetes-associated microbiota dysbiosis.

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The present study evaluated the antioxidant and antidiabetic properties of Medicago sativa and Solidago virgaurea extracts enriched in polyphenolic compounds. The extracts were obtained by accelerated solvent extraction (ASE) and laser irradiation. Then, microfiltration was used for purification, followed by nanofiltration used to concentrate the two extracts. The obtained extracts were analyzed to determine their antioxidant activity using DPPH radical scavenging and reducing power methods. The antidiabetic properties have been investigated in vitro on a murine insulinoma cell line (beta-TC-6) by the inhibition of alpha-amylase and alpha-glucosidase. M. sativa obtained by laser irradiation and concentrated by nanofiltration showed the highest DPPH center dot scavenging (EC50 = 105.2 +/- 1.1 mu g/mL) and reducing power activities (EC50 = 40.98 +/- 0.2 mu g/mL). M. sativa extracts had higher inhibition on alpha-amylase (IC50 = 23.9 +/- 1.2 mu g/mL for concentrated extract obtained after ASE, and 26.8 +/- 1.1), while S. virgaurea had the highest alpha-glucosidase inhibition (9.3 +/- 0.9 mu g/mL for concentrated extract obtained after ASE, and 8.6 +/- 0.7 mu g/mL for concentrated extract obtained after laser extraction). The obtained results after evaluating in vitro the antidiabetic activity showed that the treatment with M. sativa and S. virgaurea polyphenolic-rich extracts stimulated the insulin secretion of beta-TC-6 cells, both under normal conditions and under hyperglycemic conditions as well. This paper argues that M. sativa and S. virgaurea polyphenolic-rich extracts could be excellent natural sources with promising antidiabetic potential.

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The present study aimed to conduct a comparative investigation of the biological properties of phenolic and polysaccharide extracts obtained using an ultrasound-assisted technique from Aloe vera gel and their effects on each stage of the wound healing process in in vitro experimental models. HPLC analysis showed that the phenolic extract contained aloin, ferulic, and caffeic acid, as well as quercetin dihydrate, as major compounds. Capillary zone electrophoresis indicated the prevalence of mannose and glucose in the polysaccharide extract. Cell culture testing revealed the anti-inflammatory properties of the phenolic extract at a concentration of 0.25 mg/mL through significant inhibition of pro-inflammatory cytokines—up to 28% TNF-α and 11% IL-8 secretion—in inflamed THP-1-derived macrophages, while a pro-inflammatory effect was observed at 0.5 mg/mL. The phenolic extract induced 18% stimulation of L929 fibroblast proliferation at a concentration of 0.5 mg/mL, enhanced the cell migration rate by 20%, and increased collagen type I synthesis by 18%. Moreover, the phenolic extract exhibited superior antioxidant properties by scavenging free DPPH (IC50 of 2.50 mg/mL) and ABTS (16.47 mM TE/g) radicals, and 46% inhibition of intracellular reactive oxygen species (ROS) production was achieved. The polysaccharide extract demonstrated a greater increase in collagen synthesis up to 25%, as well as antibacterial activity against Staphylococcus aureus with a bacteriostatic effect at 25 mg/mL and a bactericidal one at 50 mg/mL. All these findings indicate that the phenolic extract might be more beneficial in formulations intended for the initial phases of wound healing, such as inflammation and proliferation, while the polysaccharide extract could be more suitable for use during the remodeling stage. Moreover, they might be combined with other biomaterials, acting as efficient dressings with anti-inflammatory, antioxidant, and antibacterial properties for rapid recovery of chronic wounds. © 2024 by the authors.

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We have developed a bienzymatic biosensor that contains acetylcholinesterase together with butyrylcholinesterase co-immobilized on the same electrode modified with a stabilized copper containing Prussian blue electrodeposited on electrodes coated with 4-aminothiophenol monolayer using diazonium chemistry and copper nanoparticles for improved sensitivity. There are organophosphorus and carbamate neurotoxic insecticides that inhibit only one of the two enzymes, e.g., pirimicarb inhibits butyrylcholinesterase at much lower concentrations than acetylcholinesterase while methomyl inhibits only acetylcholinesterase. Our system is simple and in a single measurement provides a sensitive signal for insecticides’ presence based on the inhibition of the enzyme with the highest affinity for each toxic compound. The limits of detection are 50 ng/mL pirimicarb for the bienzymatic biosensor in comparison with 400 ng/mL pirimicarb for the acetylcholinesterase biosensor and 6 ng/mL methomyl for the bienzymatic biosensor, while inhibition is obtained for the butyrylcholinesterase biosensor at 700 ng/mL. Graphical Abstract: (Figure presented.) © The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature 2024.

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Our study was aimed to characterise the hemp seeds and cake from the point of view of proximate chemical composition and bioactive compounds, as alternative feedstuffs for ruminants' nutrition. Hemp seeds and cake presented high concentrations of several trace minerals (e.g., iron, manganese, zinc), especially hemp cake had the higher content of these compounds (0.001

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Lately, there has been increased interest in the development of phytochemical alternatives for the prevention and treatment of type 2 diabetes, the alternatives that are able to reduce or prevent glucose absorption by inhibiting digestive enzymes. In this context, this study aims to analyze the inhibitory alpha-amylase and alpha-glucosidase activities of Artemisia abrotanum and Symphytum officinale polyphenolic compound-rich extracts obtained by membrane technologies (micro- and ultrafiltration). Polyphenols and flavones content, HPLC-MS polyphenolic compounds profiling, antioxidant activity, and cytotoxic potential of these herbs were determined. Major phenolic acid compounds were chlorogenic acid, ellagic acid, caffeic acid, and rosmarinic acid. The flavone content was higher in the case of A. abrotanum extracts, and the major compounds were rutin and umbelliferone. The polyphenolic-rich extract of A. abrotanum had the highest quantities of polyphenols, 977.75 mu g/mL, and flavones, 552.85 mu g/mL, as well as a pronounced alpha-amylase inhibitory activity (IC50 1881.21 +/- 1.8 mg/mL), a value close to acarbose inhibitory activity (IC50 1110.25 +/- 8.82 mg/mL) that was used as the control for both enzymes. The alpha-glucosidase inhibitory activity was higher for both herb extracts, more pronounced for S. officinale polyphenolic-rich extract (IC50 291.56 +/- 2.1 mg/mL), a value higher than that of acarbose (IC50 372.35 +/- 3.2 mg/mL). These plants show potential as a complementary therapy for type 2 diabetes management.

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Ultrasound generates cavities in liquids with high-energy behaviour due to large pressure variations, leading to (bio)chemical effects and material modification. Numerous cavity-based treatments in food processes have been reported, but the transition from research to industrial applications is hampered by specific engineering factors, such as the combination of several ultrasound sources, more powerful wave generators or tank geometry. The challenges and development of cavity-based treatments developed for the food industry are reviewed with examples limited to two representative raw materials (fruit and milk) with significantly different properties. Both active compound extraction and food processing techniques based on ultrasound are taken into consideration.

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In recent years, the wine industry has shown a considerable degree of interest in the occurrence of melatonin in wines. Sample pretreatment may be the most important step in trace analysis. Since wine is a complex matrix and melatonin is present in low amounts (ppb), an adequate extraction technique is required. In this study, the effect of several extraction methods, such as solid phase extraction (SPE), Quick, Easy, Cheap, Effective, Rugged, and Safe extraction (QuEChERS), and dispersive liquid-liquid micro-extraction (DLLME) was studied and the variable parameters that can arise throughout the extraction process were optimized to obtain the best results. A high-performance liquid chromatography with fluorescence detector (HPLC-FL) method was adapted and validated, including measurement uncertainty, for the analysis of melatonin in wines and to assess the efficiency of the extraction yield. After comparing the acquired results, the DLLME method was optimized. Extraction recoveries values ranging from 95 to 104% demonstrated that the approach may be successfully applied for the extraction and concentration (enrichment factor of almost eight) of melatonin in wine samples prior to HPLC-FL analysis. The first report of melatonin levels in Feteasca Neagra wines has been made. The data obtained for Cabernet Sauvignon revealed that the final levels of melatonin in the wines are dependent on the winemaking process.

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Until recently, the main antioxidant role among wine constituents was attributed to polyphenolic compounds, but once the presence of melatonin in wines was confirmed, an interesting new field of research opened up due to its possible synergistic effects with other antioxidants in the winemaking process, which may lead to a change in the profile of polyphenolic compounds and antioxidant activity. In order to investigate the evolution of active principles from the phenylpropanoid metabolism associated with the synergistic effects of melatonin, for the first time, a melatonin treatment was performed in the pre-stage of the different winemaking processes of Feteasca Neagra and Cabernet Sauvignon wines with different melatonin concentrations. After comparing the acquired results for the evolution of the polyphenolic compound profile and antioxidant activity of treated wines, we ascertained an increase in the antioxidant compound concentrations, especially in resveratrol, quercetin, and cyanidin-3-glucoside, directly proportional to the used melatonin concentration; an intensification in activity of PAL and C4H enzymes; and the modification in the expression of specific anthocyanin biosynthesis genes, especially UDP-D-glucose-flavonoid-3-O-glycosyltransferase. It was also shown that the application of melatonin in the pre-stage of the winemaking process can be successfully used to obtain red wines with increased antioxidant activity (almost 14%).

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A new method for the determination of the antiplatelet drug dipyridamole (DIP) in pharmaceuticals using a molecularly imprinted polymer (MIP)-modified pencil graphite electrode (PGE) is proposed. The modified electrode was prepared simply and rapidly by electropolymerization of caffeic acid (CA) in the presence of DIP and subsequent DIP extraction with ethanol, resulting in a cost-effective, eco-friendly disposable modified electrode (MIP_PGE). Several working conditions (monomer and template concentration, number of voltametric cycles, scan rate extraction time, and solvent) for the MIP_PGE preparation were optimized. The differential pulse voltammetric (DPV) oxidation signal of DIP obtained at MIP_PGE was 28% higher than that recorded at bare PGE. Cyclic voltammetry emphasized DIP irreversible, pH-dependent, diffusion-controlled oxidation at MIP_PGE. Differential pulse and adsorptive stripping voltammetry at MIP_PGE in phosphate buffer solution pH = 7.00 were applied for the drug quantitative determination in the range of 1.00 x 10(-7)-1.00 x 10(-5) and 1.00 x 10(-8)-5.00 x 10(-7) mol/L DIP, respectively. The obtained limits of detection were at the tens nanomolar level.

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The main strategy of this study was to combine the traditional perspective of using medicinal extracts with polymeric scaffolds manufactured by an engineering approach to fabricate a potential dressing product with antimicrobial properties. Thus, chitosan-based membranes containing S. officinalis and H. perforatum extracts were developed and their suitability as novel dressing materials was investigated. The morphology of the chitosan-based films was assessed by scanning electron microscopy (SEM) and the chemical structure characterization was performed via Fourier transform infrared spectroscopy (FTIR). The addition of the plant extracts increased the sorption capacity of the studied fluids, mainly at the membrane with S. officinalis extract. The membranes with 4% chitosan embedded with both plant extracts maintained their integrity after being immersed for 14 days in incubation media, especially in PBS. The antibacterial activities were determined by the modified Kirby-Bauer disk diffusion method for Gram-positive (S. aureus ATCC 25923, MRSA ATCC 43300) and Gram-negative (E. coli ATCC 25922, P. aeruginosa ATCC 27853) microorganisms. The antibacterial property was enhanced by incorporating the plant extracts into chitosan films. The outcome of the study reveals that the obtained chitosan-based membranes are promising candidates to be used as a wound dressing due to their good physico-chemical and antimicrobial properties.

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Berries of three Romanian Lonicera caerulea cultivars 'Cera', 'Kami', and 'Loni', grown at the Research Institute for Fruit Growing, Pitesti, Romania, were analyzed between 2020 and 2022 in terms of chemical composition. The study aimed to determine the concentrations of some compounds with antioxidant activity, highlight the most valuable cultivar, encourage the consumption of honeysuckle berries, and indirectly stimulate growers' interest in this little-known species in Romania. Some phenolic compounds-lycopene, beta-carotene, and vitamin C-were quantified. As a result of the study, the 'Loni' cultivar's high total phenolic content, flavonoids, anthocyanins, vitamin C, lycopene, chlorogenic and neochlorogenic acids, catechin, and rutin are to be noted. 'Cera' cultivar had the highest cryptochlorogenic acid content, and 'Kami' summarized the highest carotenoid level. These characteristics indicated that the three honeysuckle cultivars' berries could have multiple uses, from fresh consumption, as part of a diet focused on maintaining human health, to being used as raw materials in the para-pharmaceutical industry, to obtain food supplements. The novelty characteristics and the nutritional value of its berries highlighted by this study have indicated that honeysuckle can become a crop of interest and profitability.

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The administration of chokeberry extract in vitro in the GIS1 system was evaluated for the modulation capacity of the dysbiotic pattern resulting from the consumption of stevia. The microbial pattern determined by molecular method, the metabolomic one (fatty acids), the evolution of the antioxidant status, and the cytotoxic effect were determined comparatively for six months. This study presented for the first time that Aronia extract has a strong antimicrobial effect but also a presence of new organic acids that can be used as a biomarker. The functional supplement had the impact of a gradual increase in antioxidant status (DPPH scavenging activity) for up to three months and a subsequent decrease correlated with the reduction of the microbial load (especially for Enterobacteriaceae). The effect on metabolomic activity was specific, with butyric acid being generally unaffected (0.6-0.8 mg/mL) by the antimicrobial effect manifested after three months of administration. The pH was strongly acidic, corresponding to the constant presence of maximum values for acetic and lactic acid. The non-selective elimination of a part of the microbiota could also be correlated with a decrease in metabolomic efficiency. The results in the GIS1 system indicated for the first time that the controlled use of this extract had a pronounced antimicrobial and cytotoxic effect. This has helped to correct the dysbiotic pattern that results after the long-term use of sweeteners based on an increase of 0.2 log UFC/mL for favorable strains.

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Brewer's spent yeast (BSY) is a byproduct of the beer industry, rich in proteins and bioactive compounds. The effects of BSY were investigated through a 6-week feeding trial on 30 lactating dairy Blackhead sheep (54.7 +/- 5.66 kg, 177.34 days in milk) distributed under a completely randomised design in two groups: a control group (with soybean meal and sunflower meal as protein sources), and a BSY group, where soybean meal was totally replaced by BSY (5.4% inclusion, DM basis). The inclusion of BSY led to a 25% decrease in ruminal propionate and in the acetate/propionate ratio. BSY influenced the milk fatty acid profile by significantly decreasing the omega 6: omega 3 ratio and increasing the contents of caproic, capric, and lauric acids. Also, the inclusion of BSY was associated with an increase in the milk's total polyphenols. Consistently, determinations of the parameters of the milk fat's oxidative stability revealed a decrease in conjugated diene contents. Moreover, the mineral contents of milk were influenced, with an increase in Ca content noted. Overall, these results indicate that BSY represents an alternative feedstuff for ruminants' nutrition, which could have the potential to induce changes in ruminal fermentation and milk composition that are beneficial for consumers.

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The regular administration of antibiotics is a public concern due to the prejudices of large population groups and the high frequency with which antimicrobial products are prescribed. The current study aimed to evaluate the in vitro effect of a new extract from Boletus edulis (BEE) on the human microbiota. One of the disadvantages of this extensive use is the disruption of the human microbiota, leading to potential negative health consequences. The in vitro evaluation of BEE consisted in determining its cytotoxicity, influence on the concentration of four types of cytokines (IL-6, IL-10, IL-1 & beta;, TNF & alpha;), and capacity to modulate the human microbiota after administering antibiotics. The latter was assessed by microbiome analysis and the evaluation of short-chain fatty acid synthesis (SCFAs). Simultaneously, the content of total polyphenols, the antioxidant capacity, and the compositional analysis of the extract (individual polyphenols composition) were determined. The results showed that BEE modulates the microbial pattern and reduces inflammatory progression. The data demonstrated antioxidant properties correlated with the increase in synthesizing some biomarkers, such as SCFAs, which mitigated antibiotic-induced dysbiosis without using probiotic products.

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Brewer’s spent yeast (BSY) is a byproduct of the beer industry, rich in proteins and bioactive compounds. The effects of BSY were investigated through a 6-week feeding trial on 30 lactating dairy Blackhead sheep (54.7 ± 5.66 kg, 177.34 days in milk) distributed under a completely randomised design in two groups: a control group (with soybean meal and sunflower meal as protein sources), and a BSY group, where soybean meal was totally replaced by BSY (5.4% inclusion, DM basis). The inclusion of BSY led to a 25% decrease in ruminal propionate and in the acetate/propionate ratio. BSY influenced the milk fatty acid profile by significantly decreasing the omega 6: omega 3 ratio and increasing the contents of caproic, capric, and lauric acids. Also, the inclusion of BSY was associated with an increase in the milk’s total polyphenols. Consistently, determinations of the parameters of the milk fat’s oxidative stability revealed a decrease in conjugated diene contents. Moreover, the mineral contents of milk were influenced, with an increase in Ca content noted. Overall, these results indicate that BSY represents an alternative feedstuff for ruminants’ nutrition, which could have the potential to induce changes in ruminal fermentation and milk composition that are beneficial for consumers. © 2023 by the authors.

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The regular administration of antibiotics is a public concern due to the prejudices of large population groups and the high frequency with which antimicrobial products are prescribed. The current study aimed to evaluate the in vitro effect of a new extract from Boletus edulis (BEE) on the human microbiota. One of the disadvantages of this extensive use is the disruption of the human microbiota, leading to potential negative health consequences. The in vitro evaluation of BEE consisted in determining its cytotoxicity, influence on the concentration of four types of cytokines (IL-6, IL-10, IL-1β, TNFα), and capacity to modulate the human microbiota after administering antibiotics. The latter was assessed by microbiome analysis and the evaluation of short-chain fatty acid synthesis (SCFAs). Simultaneously, the content of total polyphenols, the antioxidant capacity, and the compositional analysis of the extract (individual polyphenols composition) were determined. The results showed that BEE modulates the microbial pattern and reduces inflammatory progression. The data demonstrated antioxidant properties correlated with the increase in synthesizing some biomarkers, such as SCFAs, which mitigated antibiotic-induced dysbiosis without using probiotic products. © 2023 by the authors.

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<h2 id="html-abstract-title">Abstract</h2> <div>Recently, there has been increased interest in the discovery of new natural herbal remedies for treating diabetes and inflammatory diseases. In this context, this work analyzed the antidiabetic and anti-inflammatory potential of&nbsp;Artemisia absinthium,&nbsp;<span class="html-italic">Artemisia vulgaris</span>&nbsp;and&nbsp;Trigonella foenum-graecum&nbsp;herbs, which have been studied less from this point of view. Therefore, extracts were prepared and processed using membrane technologies, micro- and ultrafiltration, to concentrate the biologically active principles. The polyphenol and flavone contents in the extracts were analyzed. The qualitative analysis of the polyphenolic compounds was performed via HPLC, identifying chlorogenic acid, rosmarinic acid and rutin in&nbsp;<span class="html-italic">A. absinthium</span>; chlorogenic acid, luteolin and rutin in&nbsp;A. vulgaris; and genistin in&nbsp;<span class="html-italic">T. foenum-graecum</span>. The antidiabetic activity of the extracts was analyzed by testing their ability to inhibit &alpha;-amylase and &alpha;-glucosidase, and the anti-inflammatory activity was analyzed by testing their ability to inhibit hyaluronidase and lipoxygenase. Thus, the concentrated extracts of&nbsp;T. foenum-graecum&nbsp;showed high inhibitory activity on a-amylase&mdash;IC₅₀&nbsp;= 3.22 &plusmn; 0.3 &mu;g/mL&mdash;(compared with acarbose&mdash;IC₅₀&nbsp;= 3.5 &plusmn; 0.18 &mu;g/mL) and high inhibitory activity on LOX&mdash;IC₅₀&nbsp;= 19.69 &plusmn; 0.52 &mu;g/mL (compared with all standards used). The concentrated extract of&nbsp;A. vulgaris&nbsp;showed increased &alpha;-amylase inhibition activity&mdash;IC₅₀&nbsp;= 8.57 &plusmn; 2.31 &mu;g/mL&mdash;compared to acarbose IC₅₀&nbsp;= 3.5 &plusmn; 0.18 &mu;g/mL. The concentrated extract of&nbsp;A. absinthium&nbsp;showed pronounced LOX inhibition activity&mdash;IC₅₀&nbsp;= 19.71 &plusmn; 0.79 &mu;g/mL&mdash;compared to ibuprofen&mdash;IC₅₀ = 20.19 &plusmn; 1.25 &mu;g/mL.</div>

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Recently, there has been increased interest in the discovery of new natural herbal remedies for treating diabetes and inflammatory diseases. In this context, this work analyzed the antidiabetic and anti-inflammatory potential of Artemisia absinthium, Artemisia vulgaris and Trigonella foenum-graecum herbs, which have been studied less from this point of view. Therefore, extracts were prepared and processed using membrane technologies, micro- and ultrafiltration, to concentrate the biologically active principles. The polyphenol and flavone contents in the extracts were analyzed. The qualitative analysis of the polyphenolic compounds was performed via HPLC, identifying chlorogenic acid, rosmarinic acid and rutin in A. absinthium; chlorogenic acid, luteolin and rutin in A. vulgaris; and genistin in T. foenum-graecum. The antidiabetic activity of the extracts was analyzed by testing their ability to inhibit alpha-amylase and alpha-glucosidase, and the anti-inflammatory activity was analyzed by testing their ability to inhibit hyaluronidase and lipoxygenase. Thus, the concentrated extracts of T. foenum-graecum showed high inhibitory activity on a-amylase-IC50 = 3.22 +/- 0.3 mu g/mL-(compared with acarbose-IC50 = 3.5 +/- 0.18 mu g/mL) and high inhibitory activity on LOX-IC50 = 19.69 +/- 0.52 mu g/mL (compared with all standards used). The concentrated extract of A. vulgaris showed increased alpha-amylase inhibition activity-IC50 = 8.57 +/- 2.31 mu g/mL-compared to acarbose IC50 = 3.5 +/- 0.18 mu g/mL. The concentrated extract of A. absinthium showed pronounced LOX inhibition activity-IC50 = 19.71 +/- 0.79 mu g/mL-compared to ibuprofen-IC50 = 20.19 +/- 1.25 mu g/mL.

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Hypertension is a frequent comorbidity in patients with heart failure; therefore, blood pressure management for these patients is widely recommended in medical guidelines. Bee pollen and postbiotics that contain inactivated probiotic cells and their metabolites have emerged as promising bioactive compounds sources, and their potential role in mitigating cardiovascular (CV) risks is currently being unveiled. Therefore, this preliminary study aimed to investigate the impact of a lactic-fermented bee pollen postbiotic (FBPP) on the CV microbiota via in vitro tests. A new isolated Lactobacillus spp. strain from the digestive tract of bees was used to ferment pollen, obtaining liquid and dried atomized caps postbiotics. The modulating effects on a CV microbiota that corresponds to the pathophysiology of hypertension were investigated using microbiological methods and qPCR and correlated with the metabolic profile. Both liquid and dried FBPPs increased the number of the beneficial Lactobacillus spp. and Bifidobacterium spp. bacteria by up to 2 log/mL, while the opportunistic pathogen E. coli, which contributes to CV pathogenesis, decreased by 3 log/mL. The short-chain fatty acid (SCFA) profile revealed a significant increase in lactic (6.386 +/- 0.106 g/L) and acetic (4.284 +/- 0.017 g/L) acids, both with known antihypertensive effects, and the presence of isovaleric acid, which promotes a healthy gut microbiota. Understanding the impact of the FBPP on gut microbiota could lead to innovative strategies for promoting heart health and preventing cardiovascular diseases.

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The aim of this paper is to study the applications of enzymes, as ecological alternatives in the leather industry. The research proposes to create ecologic leathers/furs with additional functions (non-toxic, with high-quality of soft, well-degreased surfaces) through the use of original enzyme-based biotechnologies, as new additives for leather/fur processing intended for everyday use. Another application of the enzymes studied in this paper is the development of a novel technology based on enzymes and membrane technique, for purifying wastewaters from the leather industry. We selected and analytically characterized lipases, proteases, and also new enzymes: lysozyme, tryptophan deaminase for use in leather industry. The goal was to obtain leathers/furs for everyday use, with high-performance characteristics, by processing them with enzymes - as new additives that have not been used so far in the leather industry as an alternative to the use of potentially polluting chemical materials. Complex and original technologies of ecological bioprocessing of leather/furs were used. The innovation consists in developing new biotechnologies for leather/fur with enzymatic additives in order to achieve ecologic leathers or fur articles. These biotechnologies provided advanced performances for surface quality: intense and bright colors, soft, well-degreased, and resistant to abrasion and water. © 2023, Inst. Nat. Cercetare-Dezvoltare Text. Pielarie. All rights reserved.

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New bioemulsions were created using biotechnologies based on lavender extract (oil) and two surfactants: Tween® 20 and Tween® 80 mixture: E1 – lavender oil/Tween® 20/water; E2 – lavender oil/ Tween® 80/water; E3 – lavender oil/Tween® 20 and Tween® 80 (ratio 1:1)/water, for different concentrations (28.56%, 7.14%) of lavender oil, in order to improve surface properties with applications in leather industry. More concentrated emulsions with oil lavender (28.56%) were marked E1c, E2c, E3c. In the process of finishing the leathers by spraying with six types of emulsions obtained compared to an untreated leather, the aim was to improve the antifungal, antimicrobial properties as well as the softness, appearance of the leathers. The order of introducing components in the developed biotechnologies, the working conditions, and especially the choice of the concentration of surfactants >CMC, are essential in the solubilization of vegetable oils and obtaining the desired bioemulsions. Comparatively, bioemulsions were made for the version with two surfactants, but instead of lavender, immortelle was introduced, resulting in emulsions: Lemulsion, Iemulsion. The bioemulsions and leathers processed with them were analyzed by FTIR-ATR spectroscopy, DLS and microbiological tests. It can be seen that the leather with the largest amount of lavender after processing with concentrated emulsions is E3c (having the highest intensity over the entire spectral range) and the maximum absorption specific to lavender oil was found. The lavender oil is fixed better on the leathers than the immortelle oil, with the new bioemulsions created. © 2023 by the author(s).

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New structured emulsions were obtained by innovative technologies based on sea buckthorn extract (oil) and two surfactants, sodium dodecyl sulfate and Tween® 80 mixture: Es – sea buckthorn oil/sodium dodecyl sulfate/water; Et – sea buckthorn oil/Tween® 80/water; Est – sea buckthorn oil/sodium dodecyl sulfate and Tween® 80 (ratio 1:1)/water, for different concentrations of sea buckthorn extract oil, in order to improve surface properties with applications in leather industry. Sea buckthorn extract (oil) has a strong antimicrobial and antifungal effect due to its content in: vitamins C and E, phytosterols, fatty acids, antioxidants and amino acids. The order of introduction of the components in innovative technologies, the working conditions and especially the choice of the concentration of surfactants >CMC, are essential in the solubilization of sea buckthorn oil and in obtaining the structured emulsions. The emulsions were characterized by optical microscopy with sea buckthorn oil at 23-50°C. The changes in the aggregation process were observed for each type of emulsion, the influence of temperature and the solubilization of sea buckthorn oil. Dynamic light scattering (DLS) for the emulsions showed the stability, concentration, particle size, polydispersity, zeta potential. The antimicrobial properties were analyzed by microbiological tests. FTIR measurements highlighted the interaction mechanism of surfactants with sea buckthorn oil from the structured emulsions. The leather samples were microbiologically tested, and antimicrobial and antifungal effects were observed. The new structured emulsions are original due to the successful inclusion of sea buckthorn extract (oil) with high potential for improved surface properties with applications in the leather industry. © 2023 by the author(s).

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Sensitive and stable electrodes modified with 4-aminothiophenol were developed for heavy metal detection based on coordination bonds between thiol moieties and analyte. The electrodes were modified using diazonium chemistry in one step modification protocol. The presence of 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) in the electrodeposition media avoids the formation of multilayers and improves the performances due to low surface passivation and good electrochemical transfer at the interface with the solution. Electrodeposition of the organic layer on the electrode surface by chronopotentiometry allowed a good control of the electrode modification process, avoids passivation, and leads to reproducible layers with improved characteristics in comparison with modifications carried out by cyclic voltammetry or chronoamperometry. The electrode was able to detect Pb(II) by differential pulse voltammetry with a linear range of 2.5-400 mu g l(-1) and the detection limit of 1.2 mu g l(-1) and Cd(II) with the calibration line in the range of 2.5-400 mu g l(-1) and a detection limit of 1.5 mu g l(-1). Low interferences were observed and the electrodes were applied for analysis of real samples: fruits pomace and waters. (C) 2022 The Electrochemical Society (ECS). Published on behalf of ECS by IOP Publishing Limited.

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Few biosensors are reported for usage in combination with the organic solvent due to their negative impact on the enzymes. The usage of ternary water-organic solvent mixtures in combination with acetylcholinesterase biosensors allows to increase the useable total content of organic solvents with minimum negative effects to a higher content in comparison with a single organic solvent in water. The combination of acetonitrile/ethanol/ water has a smaller negative effect on both enzyme activity and inhibition by insecticides in comparison with acetonitrile/methanol/water mixtures. The insecticides were eluted from solid-phase extraction (SPE) columns with a binary mixture of organic solvents acetonitrile/ethanol in 1/3 ratio and subsequently analysed with an acetylcholinesterase biosensor and the optimum total content of organic solvents of 12%. The analytical method allows the analysis of complex samples with improved selectivity and at improved limits of detection for chlorpyrifos-oxon and carbofuran analysis in river waters and soil samples. The usage of mixtures of organic solvents in combination with enzymes is an interesting approach that allows working with a higher total content of organic solvents than each individual solvent.

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Banana peel, a little-used waste, contains a high amount of biologically active compounds. The aim of the study is to demonstrate in vitro, the antioxidant, cytotoxic, and antimicrobial effects of hydroalcoholic extracts from yellow (BP) and red (BPR) banana peels. The analysis of the extracts by Capillary Zone Electrophoresis (CZE) has confirmed the presence of several bioactive compounds. BPR has a higher in vitro antioxidant activity than BP, which correlates with a significant cytotoxic, antimicrobial effect, with a UVA/UVB rate of 0.9. In the case of BPR, the results confirm the presence of isoquercitrin and kaempferol in a 1:3 ratio. The bioactive compounds from the extracts have shown a different interaction with HCT-8 cell lines and with tested bacterial strains with pathogenic properties. The HCA analysis proved the biological value of BPR to reduce oxidative stress and its potential use in natural products.

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This study presents the preparation of hybrid nanofiltration membranes based on poly(1,4-phenylene ether ether sulfone), polyacrylonitrile, poly(vinyl pyrrolidone), and SBA-15 mesoporous silica. Laser treatment of polymeric solutions to enhance the hydrophilicity and performance of membranes was investigated. The membranes' structure was characterized using scanning electron (SEM) and atomic force (AFM) microscopy and contact angle measurements. The addition of PAN in the casting solution produced significant changes in the membrane structure, from finger-like porous structures to sponge-like porous structures. Increased PAN concentration in the membrane composition enhanced the hydrophilicity of the membrane surface, which also accounted for the improvement in the antifouling capabilities. The permeation of apple pomace extract and the content of polyphenols and flavonoids were used to evaluate the efficacy of the hybrid membranes created. The results showed that the hybrid nanofiltration membranes based on PPEES/PAN/PVP/SBA-15: 15/5/1/1 and 17/3/1/1 exposed to laser for 5 min present a higher rejection coefficient to total polyphenols (78.6 +/- 0.7% and 97.8 +/- 0.9%, respectively) and flavonoids (28.7 +/- 0.2% and 50.3 +/- 0.4%, respectively) and are substantially better than a commercial membrane with MWCO 1000 Da or PPEES-PVP-based membrane.

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Antibiotics are antibacterial agents applied in human and veterinary medicine. They are also employed to stimulate the growth of food-producing animals. Despite their benefits, the uncontrolled use of antibiotics results in serious problems, and therefore their concentration levels in different foods as well as in environmental samples were regulated. As a consequence, there is an increasing demand for the development of sensitive and selective analytical tools for antibiotic reliable and rapid detection. These requirements are accomplished by the combination of simple, cost-effective and affordable electroanalytical methods with molecularly imprinted polymers (MIPs) with high recognition specificity, based on their lock and key working principle, used to modify the electrode surface, which is the heart of any electrochemical device. This review presents a comprehensive overview of MIP-modified carbon-based electrodes developed in recent years for antibiotic detection. The MIP preparation and electrode modification procedures, along with the performance characteristics of sensors and analytical methods, as well as the applications for the antibiotics' quantification from different matrices (pharmaceutical, biological, food and environmental samples), are discussed. The information provided by this review can inspire researchers to go deeper into the field of MIP-modified sensors and to develop efficient means for reliable antibiotic determination.

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The main objective of this study was to evaluate the quality of essential oil (EO) and hydrolate (HY) obtained from a new Romanian variety of hyssop (Hyssopus officinalis L., Lamiaceae family), namely `Catalin'. The chemical composition and the concentration of the compounds was established by gas chromatography coupled to mass spectrometry (GC/MS). The main constituents identified in hyssop EO and HY were cispinocamphone (34.63% and 67.00%), trans-pinocamphone (11.72% and 14.58%), thujenol (1.39% and 6.05%). The evaluation of the antioxidant capacity was performed by three methods (DPPH, ABTS and FRAP), EO proving a higher oxidizing activity compared to HY one. The antimicrobial activity of the essential oil was evaluated in vitro, in order to detect its ability to inhibit G phytopathogenic bacteria (Pseudomonas syringae) and plant pathogenic fungi (Fusarium oxysporum). Eugenol, linalool and estragole standards were used as reference volatile compounds. Regarding Pseudomonas syringae (LMG5090) bacterium, assays showed that hyssop oil does not inhibit its growth. Estragole and eugenol showed pronounced antibacterial activity in all tested concentrations, both in the first 24 hours of incubation and after 3 days. Linalool instead has bacteriostatic activity only at high concentrations (50% and 100%), an inhibitory activity that is maintained only in the first 24 hours of incubation. The results obtained against Fusarium oxysporum reveal that the EO tested has no fungicidal activity but only fungistatic, and it is able to delay mycelial growth and the degree of inhibition depending on the concentration used.

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A simple and rapid differential pulse voltammetric (DPV) method using a single-use electroactivated pencil graphite electrode (PGE*) is proposed for the rapid screening of the total content of polyphenolics (TCP) with intermediate antioxidant power (AOP) in grapefruit peel and fresh juice. The results were compared and correlated with those provided by the HPLC-DAD-MS method. NG voltammetric behavior at PGE* was studied by cyclic voltammetry and an oxidation mechanism was suggested. The experimental conditions (type of PGE, electroactivation procedure, pH, nature and concentration of supporting electrolyte) for NG DPV determination were optimized. The NG peak current varied linearly with the concentration in the ranges 1.40 x 10(-6)-2.00 x 10(-5) and 2.00 x 10(-5)-1.40 x 10(-4) mol/L NG and a limit of detection (LoD) of 6.02 x 10(-7) mol/L NG was attained. The method repeatability expressed as relative standard deviation was 7.62% for the concentration level of 2.00 x 10(-6) mol/L NG. After accumulation for 240 s of NG at PGE* the LoD was lowered to 1.35 x 10(-7) mol/L NG, the linear range being 6.00 x 10(-7)-8.00 x 10(-6) mol/L NG. The developed electrochemical system was successfully tested on real samples and proved to be a cost-effective tool for the simple estimation of the TCP with intermediate AOP in citrus fruits.

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Recent agricultural research aims to identify novel applications for plant extracts as efficient defenses against weeds, insects, or phytopathogenic agents. The main goal of the present study was to evaluate two new varieties of basil (Ocimum basilicum L., fam. Lamiaceae), Yellow basil, Aromat de Buzau variety and Red-violet basil, Serafim variety. The basil varieties were studied under different aspects regarding biochemical characterization using GC-MS, antioxidant activity evaluated under three methods (DPPH, ABTS, FRAP), and antimicrobial properties (for three G-bacteria: Perctobacterium carotovorum, Pseudomonas marginalis, Pseudomonas syringae and three phytopathogenic fungi: Rhizoctonia solani, Fusarium oxysporum, Botrytis cinerea). The results showed that linalool (39.28%; 55.51%), estragole (31.48%; 9.78%), and eugenol (5.42%; 7.63%) are the main compounds identified in the extracts, validating the high antioxidant activity of the studied essential oils and floral waters. When applied in high concentrations, essential oils have shown a potential bactericidal effect on P. carotovorum as well as a potential fungicidal effect on R. solani and B. cinerea.

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Few biosensors are reported for usage in combination with the organic solvent due to their negative impact on the enzymes. The usage of ternary water–organic solvent mixtures in combination with acetylcholinesterase biosensors allows to increase the useable total content of organic solvents with minimum negative effects to a higher content in comparison with a single organic solvent in water. The combination of acetonitrile/ethanol/water has a smaller negative effect on both enzyme activity and inhibition by insecticides in comparison with acetonitrile/methanol/water mixtures. The insecticides were eluted from solid-phase extraction (SPE) columns with a binary mixture of organic solvents acetonitrile/ethanol in 1/3 ratio and subsequently analysed with an acetylcholinesterase biosensor and the optimum total content of organic solvents of 12%. The analytical method allows the analysis of complex samples with improved selectivity and at improved limits of detection for chlorpyrifos-oxon and carbofuran analysis in river waters and soil samples. The usage of mixtures of organic solvents in combination with enzymes is an interesting approach that allows working with a higher total content of organic solvents than each individual solvent. © 2022 Elsevier Inc.

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Sustainable economy means reducing the carbon footprint and minimizing the amount of waste released from productive activities. This paper presents the characterization of composites obtained from by-products of the leather industry based on collagen and keratin extracts. The protein composites have specific properties for the agricultural field and industrial applications in accordance with the current recommendations for a sustainable economy. Chemical-enzymatic hydrolysis of leather and wool by-products was performed for protein extraction. The composites were obtained by addition and crosslinking of collagen and keratin extracts with tannins from vegetable byproducts. The characterization of composites was performed based on the results of analytical investigations by physico-chemical methods: volumetry, potentiometry, Texture Analysis, Dynamic Light Scattering, colorimetry, microscopy. It has been found that new collagen and keratin extracts contain small and medium components size, useful for the biostimulation of agricultural crops, but also contain large size components which give adhesive and film-forming properties, useful in industrial applications. © 2022 Toate drepturile asupra acestei ediţii sunt rezervate editorilor.

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The aim of the paper is to obtain new byproducts based on surfactants (gemini – polymethylene-α, ω-bis (N, N-dialkyl-N-deoxy-d-glucitolammonium iodides or bolaform – demecarium bromide) and protein hydrolysates (keratin and collagen) with micro and macro nutrients for applications in agriculture. A method was developed to include micro and macronutrients in keratin and collagen hydrolysates, in order to obtain new byproducts-bioemulsions (stable because of surfactants), with final goal of application as a new class of root fertilizers for cereals (e.g., corn). The newly obtained byproducts (bioemulsions based on surfactants) were characterized by: dynamic light scattering measurements, contact angle, optical microscopy and microbiological tests against fungal attack of Fusarium spp. and Botrytis cinerea. Better results were obtained for Gemini surfactant based on sugar – polymethylene-α, ω-bis (N, N-dialkyl-N-deoxy-d-glucitolammonium iodides) due to the properties such as: biodegradability, nontoxicity and adherence to surfaces. The new fertilizer created in this research – bioemulsions based on surfactants, can support the general structure of the grains as well as the chlorophyll content, increasing the growth yield. The fertilizer is indicated for any type of crops and soils, with recommended use as additional fertilizer for plants (cereals) in the vegetation and growth phases, with a maximum need for nutrients. © 2022 Toate drepturile asupra acestei ediţii sunt rezervate editorilor.

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The influence of a classical surfactant – palmitoyl-glycylglycine and bola amphiphilic – demecarium bromide upon the elastin membrane preparation and separation mechanism of turmeric from aqueous solutions was studied by: UV-VIS spectroscopy, scanning electron microscopy, dynamic light scattering and separation rates. The tensile strength and hydrophobic property were improved by introducing a surfactant (classic or bola). In this research the influence of surfactants upon the microporous structure and retention of turmeric from aqueous solutions was studied. The biomembranes were produced by a casting-solvent evaporation technique. The elastin powder was dissolved in a water-acetic acid (70:30 v/v) solution with and without plasticizer: glycerol and surfactant (classic or bola), constant continuous stirring for 5-7 hrs. at 60°C, then degassed the solution for 2 hrs. The solution was poured and afterwards maintained in the oven at 45-55°C for 5-8 hrs. Ecological biomembranes are obtained from a biodegradable biopolymer – elastin, and can be used successfully in removing turmeric from wastewaters. © 2022 by the author(s).

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New bioemulsions structured like “networks” were created by innovative technologies based on: elastin/zinc hydroxide/ (bolaamphiphiles mixture: bis [2-butyl (sodium bis-thioacetate) sodium dicarboxylate 1,10 decanediyl ester] and/or sucrose diester)/ acetic acid/water, for improved surface properties development with applications in leather industry. We used in this research two “bolaamphiphiles”. Bolaamphiphilic molecules contain a hydrophobic skeleton (e.g., one, two, or three alkyl chains, a steroid, or a porphyrin) and two water-soluble groups on both ends. The interaction of surfactants with biopolymers in aqueous medium results in the formation of different association structures. There are various morphologies of biopolymer-surfactant association complexes depending on the molecular structure of the biopolymer and surfactant, on the nature of interaction forces between solvents and surfactant or biopolymer. The innovation consists in the technologies for obtaining novel micro and nanostructured bioemulsions, and the compatibilisation with film forming polymers for leather surface finishing. Elastin/zinc hydroxide micro and nanocomposites have been stabilized with bolaamphiphilic surfactants mixture: bis [2-butyl (sodium bis-thioacetate) sodium dicarboxylate 1,10 decanediyl ester and sucrose diester in a 1:1 acetic acid/water ratio, to increase the uniformity of nanocomposites. Micro and nanostructured composites like “networks” developed as a result of biopolymer-surfactants interactions for elastin/zinc hydroxide/surfactants mixture couple in acetic acid/water system are reported by SEM microscopy and DLS analysis. A special class of micro and nanoarchitectures is represented by structures organized as “network” assemblies. The novel micro and nanocomposites can provide the hybrid film with increased resistance to rubbing and water, and to deformation. Environmentally-friendly substrates with smart multifunctional features can be obtained for various applications. © 2022 by the author(s).

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Phenyl aldehyde layers were formed on copper foils by electro-assisted diazonium reactions and subsequently functionalized with either amino-2-propanol or 2-amino-1-butanol. The anticorrosion properties of the two obtained organic films 2-[(phenylmethylidene)amino]butan-1-ol and (phenylmethylidene)amino-propan-2-ol were evaluated in aerated buffer acetate solution pH = 3.5. The electrochemical corrosion inhibition properties were investigated after different immersion times using electrochemical impedance spectroscopy and potentiodynamic polarization analysis (Tafel). Contact angle measurement confirms the hydrophobic nature of the new organic coatings and layer stability after immersion in buffer. The results showed that both developed layers provided good anticorrosion protection and the highest inhibition was achieved using 2-[(phenylmethylidene)amino]butan-1-ol coating on copper, which makes it a useful device for anticorrosion protection. Moreover, correlations between the molecular structures of the corrosion inhibitors and their protecting efficiencies have been established.

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A rapid, simple, and precise electrochemical method was developed for the determination of the total content of antibiotics containing a 5-nitrofuran ring with antibacterial activity including furazolidone, nitrofurazone, nitrofurantoin, and furaltadone in several samples. Boron-doped diamond electrode was used as the working electrode. The electrochemical properties of these compounds were evaluated by cyclic voltammetry. A differential pulse voltammetric method based on the cathodic reduction at high potentials was used for the determination of the total nitrofuran content in a mixture at pH 6.47. The voltammetric measurements showed that the proposed electrochemical method was able to identify the nitrofurazone from a mixture of antibiotics based on its anodic oxidation in alkaline medium (pH 10.6). This method presented good accuracy (between 94.5 and 102.5%) and precision (less than 3.94%), with calibration graphs starting from 50 nmol L-1. The method was applied with success for the determination of total content of compounds with 5-nitrofuran ring and for the selective determination of nitrofurazone in pharmaceutical tablets and food products (milk and honey) without pretreatment of the samples.

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Both climate change and human exploitation are major threats to plant life in mountain environments. One species that may be particularly sensitive to both of these stressors is the iconic alpine flower edelweiss (Leontopodium alpinum Colm.). Its populations have declined across Europe due to over-collection for its highly prized flowers. Edelweiss is still subject to harvesting across the Romanian Carpathians, but no study has measured to what extent populations are vulnerable to anthropogenic change. Here, we estimated the effects of climate and human disturbance on the fitness of edelweiss. We combined demographic measurements with predictions of future range distribution under climate change to assess the viability of populations across Romania. We found that per capita and per-area seed number and seed mass were similarly promoted by both favorable environmental conditions, represented by rugged landscapes with relatively cold winters and wet summers, and reduced exposure to harvesting, represented by the distance of plants from hiking trails. Modeling these responses under future climate scenarios suggested a slight increase in per-area fitness. However, we found plant ranges contracted by between 14% and 35% by 2050, with plants pushed into high elevation sites. Synthesis. Both total seed number and seed mass are expected to decline across Romania despite individual edelweiss fitness benefiting from a warmer and wetter climate. More generally, our approach of coupling species distribution models with demographic measurements may better inform conservation strategies of ways to protect alpine life in a changing world.

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Bum injuries have a major impact on population health, an optimal bum wound dressing with both healing and antibacterial effect being needed. Our purpose was to assess the healing efficacy of chitosan supports containing different quantities of a hydroalcoholic extract obtained from Impatiens noli-tangere and Symphytum officinale, in a rat bum wound model. The antibacterial effect of the extract was also assessed. The efficacy of topical daily administration of the supports and of silver sulphadiazine was evaluated by measuring the thermal lesion area. In addition, tissular hydroxyproline content and IL-6, TNF-alpha plasmatic levels were measured. The chitosan support with the highest content of plant extract showed the most pronounced healing effect. The mixed extract was shown to possess a moderate antibacterial effect, the most sensitive microorganism being S. aureus.

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The nanofiltration composite membranes were obtained by incorporation of KIT-6 ordered mesoporous silica, before and after its functionalization with amine groups, into polyphenylene-ether-ether-sulfone (PPEES) matrix. The incorporation of silica nanoparticles into PPEES polymer matrix was evidenced by FTIR and UV-VIS spectroscopy. SEM images of the membranes cross-section and their surface topology, evidenced by AFM, showed a low effect of KIT-6 silica nanoparticles loading and functionalization. The performances of the obtained membranes were appraised in permeation of Chaenomeles japonica fruit extracts and the selective separation of phenolic acids and flavonoids. The obtained results proved that the PPEES with functionalized KIT-6 nanofiltration membrane, we have prepared, is suitable for the polyphenolic compound's concentration from the natural extracts.

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Edible mushrooms are functional foods and valuable but less exploited sources of biologically active compounds. Herbal teas are a range of products widely used due to the therapeutic properties that have been demonstrated by traditional medicine and a supplement in conventional therapies. Their interaction with the human microbiota is an aspect that must be researched, the therapeutic properties depending on the interaction with the microbiota and the consequent fermentative activity. Modulation processes result from the activity of, for example, phenolic acids, which are a major component and which have already demonstrated activity in combating oxidative stress. The aim of this mini-review is to highlight the essential aspects of modulating the microbiota using edible mushrooms and herbal teas. Although the phenolic pattern is different for edible mushrooms and herbal teas, certain non-phenolic compounds (polysaccharides and/or caffeine) are important in alleviating chronic diseases. These specific functional compounds have modulatory properties against oxidative stress, demonstrating health-beneficial effects in vitro and/or In vivo. Moreover, recent advances in improving human health via gut microbiota are presented. Plant-derived miRNAs from mushrooms and herbal teas were highlighted as a potential strategy for new therapeutic effects.

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The effect of stevioside on human health is still insufficiently highlighted by recent research. The total or partial replacement of sugar with sweeteners influences the general state of health, especially the human microbiota's response as a determining factor in the onset of type 2 diabetes. The present study aimed to present the long-term (one-year) in vitro effect that regular stevioside consumption had on children's pattern microbiota. A metabolomic response was established by determining the synthesis of organic acids and a correlation with antioxidant status. An increase in the number of bacterial strains and the variation of amount of butyrate and propionate to the detriment of lactic acid was observed. The effect was evidenced by the progressive pH increasing, the reduction of acetic acid, and the proliferation of Escherichia coli strains during the simulations. Synthesis of the main short-chain fatty acids (SCFAs) was interpreted as a response (adaptation) of the microbiota to the stevioside, without a corresponding increase in antioxidant status. This study demonstrated the modulatory role of stevioside on the human microbiota and on the fermentation processes that determine the essential SCFA synthesis in maintaining homeostasis. The protection of the microbiota against oxidative stress was also an essential aspect of reducing microbial diversity.

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Enzymatic biosensors enjoy commercial success and are the subject of continued research efforts to widen their range of practical application. For these biosensors to reach their full potential, their selectivity challenges need to be addressed by comprehensive, solid approaches. This review discusses the status of enzymatic biosensors in achieving accurate and selective measurements via direct biocatalytic and inhibition-based detection, with a focus on electrochemical enzyme biosensors. Examples of practical solutions for tackling the activity and selectivity problems and preventing interferences from co-existing electroactive compounds in the samples are provided such as the use of permselective membranes, sentinel sensors and coupled multi-enzyme systems. The effect of activators, inhibitors or enzymatic substrates are also addressed by coupled enzymatic reactions and multi-sensor arrays combined with data interpretation via chemometrics. In addition to these more traditional approaches, the review discusses some ingenious recent approaches, detailing also on possible solutions involving the use of nanomaterials to ensuring the biosensors' selectivity. Overall, the examples presented illustrate the various tools available when developing enzyme biosensors for new applications and stress the necessity to more comprehensively investigate their selectivity and validate the biosensors versus standard analytical methods.

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Hesperidin (HESP) is a plant bioflavonoid found in various nutritional and medicinal products. Many of its multiple health benefits rely on the compound's antioxidant ability, which is due to the presence of oxidizable hydroxyl groups in its structure. Therefore, the present study aimed to investigate the electrochemical behavior of HESP at a cheap, disposable pencil graphite electrode (PGE) in order to develop rapid and simple voltammetric methods for its quantification. Cyclic voltammetric investigations emphasized a complex electrochemical behavior of HESP. The influence of the electrode material, solution stability, supporting electrolyte pH, and nature were examined. HESP main irreversible, diffusion-controlled oxidation signal obtained at H type PGE in Britton Robinson buffer pH 1.81 was exploited for the development of a differential pulse voltammetry (DPV) quantitative analysis method. The quasi-reversible, adsorption-controlled reduction peak was used for HESP quantification by differential pulse adsorptive stripping voltammetry (DPAdSV). The linear ranges of DPV and DPAdSV were 1.00 x 10(-7)-1.20 x 10(-5) and 5.00 x 10(-8)-1.00 x 10(-6) mol/L with detection limits of 8.58 x 10(-8) and 1.90 x 10(-8) mol/L HESP, respectively. The DPV method was applied for the assessment of dietary supplements bioflavonoid content, expressed as mg HESP.

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Resveratrol (RES) is a naturally occurring product with numerous biological activities. Despite its potential benefits, its use is limited due to its low aqueous stability and solubility in its native form. The porous sol-gel silica materials which are able to entrap different organic molecules represent new studied release carriers. The aim of this work was to generate a solid matrix to encapsulate RES ensuring protection, increased solubility and release in solutions. A non-toxic ingredient, namely beta-cyclodextrin (beta-CD), able to form inclusion complexes (ICs) with RES has been used. Ecological formulations have been processed by entrapping the RES containing ICs in silica matrices obtained from a silica colloidal sol by the aqueous route of the sol-gel method. Characterization methods (DSC, FTIR, UV-Vis, fluorescence studies, SEM) have evidenced the presence of RES-beta-CD inclusion complex in the silica powder, RES stability in the matrix and its release in aqueous and organic solutions, and the morphology of the carrier. An evaluation of the antioxidant activity of RES in the present formulation was performed by the chemiluminescence assay and RES release profile in aqueous solutions was obtained by HPLC-MS. The resulted materials can find applications in different domains. Graphic abstract

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This study investigated the potential of using the changes in polyphenol composition of red wine to enable a more comprehensive chemometric differentiation and suitable identification of authentication markers. Based on high performance liquid chromatography-mass spectrometry (HPLC-MS) data collected from Feteasca Neagra, Merlot, and Cabernet Sauvignon finished wines, phenolic profiles of relevant classes were investigated immediately after vinification (Stage 1), after three months (Stage 2) and six months (Stage 3) of storage, respectively. The data were subjected to multivariate analysis, and resulted in an initial vintage differentiation by principal component analysis (PCA), and variety grouping by canonical discriminant analysis (CDA). Based on polyphenol common biosynthesis route and on the PCA correlation matrix, additional descriptors were investigated. We observed that the inclusion of specific compositional ratios into the data matrix allowed for improved sample differentiation. We obtained simultaneous discrimination according to the considered oenological factors (variety, vintage, and geographical origin) as well as the respective clustering applied during the storage period. Subsequently, further discriminatory investigations to assign wine samples to their corresponding classes relied on partial least squares-discriminant analysis (PLS-DA); the classification models confirmed the clustering initially obtained by PCA. The benefits of the presented fingerprinting approach might justify its selection and warrant its potential as an applicable tool with improved authentication capabilities in red wines.

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Cancer is a multifactorial disease involving reprogramming of the gene function in normal cells through both genetic and epigenetic factors. The latter ones are essentially represented by chromatin remodeling factors as transcriptional control of gene expression at the nucleus level. Certain sets of tumor suppression genes controlling vital cell functions such as cell cycle, DNA repair, cell adhesion, and apoptosis are considered candidate genes for defining specific types of cancer. Their silencing may be achieved through somatic mutations or by epigenetic factors as DNA methylation and histone covalent modification. Two major DNA methylation patterns have been described in mammary gland tumors: genome hypomethylation and concomitant in situ hypermethylation in critical genes. Human mammary gland cancer has been studied through animal models, canine one offering opportunity to investigate the molecular aspects that better define the borderline between the primary inflammatory and tumor progression processes. In contrast, both humans and dogs share the same challenging environment. This work presents the preliminary results in a study of the transcriptional epigenetic markers identified in canine mammary glands during tumor development. Bisulfite mutagenesis based methylation-specific (MS)- PCR has been performed for the estimation of BRCA1, and BRCA2 gene promoter hyper-methylation profiles, concomitant to methylation sensible restriction of genomic DNA in order to estimate the global hypo-methylation status have been performed on 9 DNA samples obtained from clinically selected canine tumor tissues. Histone H3K9 trimethylated was stained by immunohistochemical methods (IHC) in normal and tumor tissues. The results are discussed through their crosstalk with DNA methylation dynamics in order to highlight the cancer initiation and progression processes in the context of heritability and the causes of sporadic cases.

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Inonotus obliquus is a parasite on the birch and other trees and is also a well-known medicinal mushroom. Its sterile conk is highly sought for its bioactive compounds such as phenols, polysaccharides, triterpenoids, and steroids. It was traditionally used to treat various gastrointestinal diseases, viral and parasitic infections, to counteract the progression of cancers, and to stimulate the immune system. We used acute gamma irradiation, followed by short-term submerged cultivation, as an oxidative stress inducer to enhance the synthesis of mycelial metabolites. The 300 Gy and 400 Gy doses showed the best results across the whole experimental design. Each assayed criterion had a different corresponding optimal stimulation dose. In one experiment, sublethal doses of irradiation triggered the dry weight of the cultured mycelium to increase by 19.764%. The free radical scavenging potential of the mycelium extracts increased by 79.83%. The total phenolic content of mycelium extracts and culture broth increased by 55.7% and 62.987%, respectively. The total flavonoid and sinapinic acid content of the broth increased by 934.678% and 590.395%, respectively. As such, gamma irradiation pre-treatment of the mycelial inoculum proved an interesting, economically and environmentally effective tool for stimulating secondary metabolite synthesis in submerged mycelium cultures. © 2021 Alexandru Petre et al., published by Sciendo.

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Phenyl aldehyde layers were formed on copper foils by electro-assisted diazonium reactions and subsequently functionalized with either amino-2-propanol or 2-amino-1-butanol. The anticorrosion properties of the two obtained organic films 2-[(phenylmethylidene)amino]butan-1-ol and (phenylmethylidene)amino-propan-2-ol were evaluated in aerated buffer acetate solution pH Æ 3.5. The electrochemical corrosion inhibition properties were investigated after different immersion times using electrochemical impedance spectroscopy and potentiodynamic polarization analysis (Tafel). Contact angle measurement confirms the hydrophobic nature of the new organic coatings and layer stability after immersion in buffer. The results showed that both developed layers provided good anticorrosion protection and the highest inhibition was achieved using 2-[(phenylmethylidene)amino]butan-1-ol coating on copper, which makes it a useful device for anticorrosion protection.Moreover, correlations between the molecular structures of the corrosion inhibitors and their protecting efficiencies have been established. © 2021 Elsevier Masson SAS. All rights reserved.

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Due to the increase of the incidence of type II diabetes nowadays there are attempts to find phytotherapeutic alternatives for the prophylaxis of this disease by inhibiting the enzymes involved in glucose uptake. Thus, in this study the α-amylase and α-glucosidase inhibitory activities of some hydroalcoholic Apium graveolens and Agropyrum repens extracts (50% EtOH, v/v, 10% weight) were analysed. Extracts were processed by membranare processes, microand ultrafiltration for obtaining rich-polyphenolic extracts. The polyphenols and flavones content and antioxidant activity of them were analysed. The extracts of both plants have shown inhibitory activities on the two digestive enzymes. © 2019 Editura Academiei Romane. All rights reserved.

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This study was focused on the phytochemical composition and biological activities of Anchusa officinalis and Melilotus officinalis polyphenolic-rich extracts obtained by nanofiltration. The high-performance liquid chromatography-mass spectrometry analysis showed that chlorogenic acid and rosmarinic acid were the main phenolic acids in both extracts. The main flavonoid compound from A. officinalis extracts is luteolin, whereas rutin and isoquercitrin are the main flavonoids in M. officinalis. M. officinalis polyphenolic-rich extract had the highest alpha-amylase (from hog pancreas) inhibitory activity (IC50 = 1.30 +/- 0.06 mu g/mL) and alpha-glucosidase (from Saccharomyces cerevisiae) inhibitory activity (IC50 = 92.18 +/- 1.92 mu g/mL). However, both extracts presented a significant alpha-glucosidase inhibitory activity. Furthermore, the hyaluronidase inhibition of polyphenolic-rich extracts also proved to be stronger (IC50 = 11.8 +/- 0.1 mu g/mL for M. officinalis and 36.5 +/- 0.2 mu g/mL for A. officinalis), but there was moderate or low lipoxygenase inhibition. The studies on the fibroblast cell line demonstrated that both A. officinalis and M. officinalis polyphenolic-rich extracts possess the cytotoxic effect at a concentration higher than 500 mu g/mL. The experimental data suggest that both extracts are promising candidates for the development of natural antidiabetic and anti-inflammatory food supplements.

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Because melatonin has strong antioxidant activity and wine is an alcoholic beverage of economic relevance, in the present work, the impact of some variable parameters that may occur in the winemaking process on the concentrations of melatonin and its precursors in Romanian wines was studied. Therefore, a sensitive and selective high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for the simultaneous analysis of melatonin, serotonin, and L-tryptophan, and some method performance parameters including selectivity, detection limit, precision (by comparing with an alternative HPLC-FL method), accuracy, and robustness were validated. These determinations are significant and the final amounts of analytes are dependent on the microorganisms involved in the winemaking process, the grape variety, geographic regions of vineyards, and aging of wines. In the future, the method may be useful to increase the melatonin content and the antioxidant activity in wines by improved steps in the winemaking process, especially based on application of selected yeasts and improved fermentation conditions.

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Since early times, various plants have been used as remedies for treating different kinds of diseases and lesions with satisfying results. The phenolic compounds are secondary metabolites from medicinal plants which include a wide category of compounds such as phenolic acids, flavonoids, tannins, stilbenes, curcuminoids, xanthones, coumarins, lignans, etc. Between these, lignans are considered important in cancer prevention and treatment, besides other beneficial health effects, e.g. antioxidant, anticarcinogenic, antimutagenic, and anti-estrogenic effects. This review summarizes the most recent literature and the most important results concerning plant lignans and their derivatives in cancer prevention and treatment, both in vitro and in vivo assessments. The mechanistic aspects will be also highlighted.

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The tendency of using herbs extracts or natural compounds extracted from herbs for preventing or treating different illnesses, including cancer, continues to be an alternative to drug use. Many studies of plant compounds aimed at finding substances with selective cytotoxicity on abnormal cells. Phenolic compounds, as important secondary metabolites from plants, are one of them. In this review, the recent literature data from the past five years about anticancer/antitumor effect of flavonoids and tannins extracted from medicinal plants are surveyed. The cytostatic/antitumor effects of the individual compounds extracted from plants and/or of the plants' polyphenolic extracts are considered, in order to point out the most significant constituents or plants with anticancer potential. The most important results concerning these compounds and their derivatives in cancer prevention and treatment, the importance of their chemical structure, their mechanism of action in vitro and in vivo, and some bioavailability aspects are discussed.

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Numerous studies have demonstrated the role of the microbiota in supporting the physiological functions, owing to its metabolomic component. The presence of biocomponents generally leads to the correction of the microbial pattern correlated with the reduction of oxidative pressure. This study aims to present the main processes that correlate the bioavailability and bioactivity of some functional components through the action of the human microbiota. The use of probiotics and prebiotics is an innovative manner involving alternatives that increase the bioavailability of certain natural or metabolic components has been proposed. Probiotic strains (Saccharomyces cerevisiae or Lactobacillus (L.) plantarum) may represent an intermediary for increasing the antioxidant bioactivity, and they may be administered in the form of a biomass enriched with functional compounds, such as phenolic acids. The limiting effect of gastrointestinal transit is, in several cases, the key to the biopharmaceutical value of new products (or supplements). The identification of newer ways of formulating supplements also involves the compatibility of different types of products, the testing of bioaccessibility, and the elimination of biotransformations.

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This work proposes a novel method for determining the composition of mixtures of natural polyphenolic compounds: caffeic acid, gallic acid, ellagic acid, rosmarinic acid and quercitrin in plants. The method is based on the formation of colored spots by these compounds upon reaction with nano-oxides of Al2O3, ZnO, MgO, CeO2, TiO2 and MoO3 impregnated on filter paper and constituting a colorimetric sensor array (CSA). The image of the colored spots was analyzed and the intensity of the blue colour (BCI) component has shown maximum sensitivity in relation to phenolic compounds. The inverse of BCI was linearly correlated with the logarithm of the individual phenolic compound concentrations. Chemometric analysis by partial least squares regression (PLSR) of 1/BCI values for 24 synthetic mixtures of the 5 phenolic compounds measured with the colorimetric sensor array has demonstrated good correlation between the actual and the predicted concentration of quercitrin. For the other phenolic compounds, the colors measured with the colorimetric sensor array were greatly influenced by the concentrations of the other components in the mixture. The method was applied to the determination of quercitrin in medicinal teas and the results were compared to those obtained by HPLC. The discussion of the results emphasizes possible interferences in the tea samples. While further optimization of the colorimetric sensor array-based method appears necessary, tailored to the particular targeted application in real samples, the proposed method for polyphenol determination has advantages that include simplicity, low cost, and portability.

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Coffee grounds are a valuable source of bioactive compounds. In Romania, most of the amount obtained is lost through non-recovery; the rest is occasionally used as organic fertilizer. The coffee grounds were selected according to the roasting degree: blonde roasted (BR), medium roasted (MR), and dark roasted (DR). The study aimed to evaluate three extracts, obtained with a mixture of ethanol/water/acetic acid (50/49.5/0.5), depending on the roasting degree. The majority phenolic component, the antioxidant, and anti-inflammatory effect, as well as the role that gastrointestinal transit had on the bioavailability of bioactive compounds were determined. Chlorogenic acid was inversely proportional to the roasting degree. BR showed the best correlation between antioxidant and anti-inflammatory activities in vitro/in vivo. The antiproliferative capacity of the extracts determined an inhibitory effect on the tumor cells. Antimicrobial activities, relevant in the control of type 2 diabetes, were exerted through the inhibition of microbial strains (Escherichia coli). Following gastric digestion, BR demonstrated a maximum loss of 20% in the stomach. The recovery of coffee grounds depended on the pattern of functional compounds and the bioavailability of the main component, chlorogenic acid.

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Herein, several nitrogen-doped nano-crystalline graphite films (N-NCG) were prepared via plasma-enhanced chemical vapor deposition (PECVD); nano-crystalline graphite (NCG) was doped by adding ammonia gas during the PECVD growth. To develop electrochemical probes that can compete with glassy carbon (GC) electrodes for anthracene sensing, the N-NCG electrodes were systematically investigated using different techniques, including atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) analysis, Raman spectroscopy, cyclic voltammetry (CV), and differential pulsed voltammetry (DPV). The obtained sensors were tested against anthracene in an acetonitrile/water mixture (80/20 v/v) wherein the N-NCG 3 and N-NCG 5 electrochemical probes showed analytical features comparable with those of the GC electrode. The best competitor for GC was N-NCG 3 in terms of linear working range (2.5 mu M-1 mM) and sensitivity (y = 6.09 x 10(-6)+ 1.21 x, r(2)= 0.9997 and y = 1.23 x 10(-5)+ 0.84 x, r(2)= 0.9959 for GC and N-NCG 3, respectively).

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Because melatonin has strong antioxidant activity and wine is an alcoholic beverage of economic relevance, in the present work, the impact of some variable parameters that may occur in the winemaking process on the concentrations of melatonin and its precursors in Romanian wines was studied. Therefore, a sensitive and selective high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for the simultaneous analysis of melatonin, serotonin, and L-tryptophan, and some method performance parameters including selectivity, detection limit, precision (by comparing with an alternative HPLC-FL method), accuracy, and robustness were validated. These determinations are significant and the final amounts of analytes are dependent on the microorganisms involved in the winemaking process, the grape variety, geographic regions of vineyards, and aging of wines. In the future, the method may be useful to increase the melatonin content and the antioxidant activity in wines by improved steps in the winemaking process, especially based on application of selected yeasts and improved fermentation conditions. © 2020 American Chemical Society

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The tendency of using herbs extracts or natural compounds extracted from herbs for preventing or treating different illnesses, including cancer, continues to be an alternative to drug use. Many studies of plant compounds aimed at finding substances with selective cytotoxicity on abnormal cells. Phenolic compounds, as important secondary metabolites from plants, are one of them. In this review, the recent literature data from the past five years about anticancer/antitumor effect of flavonoids and tannins extracted from medicinal plants are surveyed. The cytostatic/antitumor effects of the individual compounds extracted from plants and/or of the plants' polyphenolic extracts are considered, in order to point out the most significant constituents or plants with anticancer potential. The most important results concerning these compounds and their derivatives in cancer prevention and treatment, the importance of their chemical structure, their mechanism of action in vitro and in vivo, and some bioavailability aspects are discussed. © 2020 Bentham Science Publishers.

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A stable and reproducible layer of Prussian blue (PB) modified with copper was electrodeposited on carbon paper electrodes for the multiple detection of ester flavorants with a bienzymatic biosensor. Carbon fiber composite paper was investigated as high-surface, low-cost substrate for biosensor development. The pre-activation of the electrode surface by cyclic voltammetry was necessary to improve the electrochemical properties before the electrochemical deposition of Prussian blue-copper film (PB-Cu). The stability and the reproducibility of the obtained PB-Cu carbon paper electrode was demonstrated at pH 7.4, optimum for biosensor development. The developed biosensor is based on the immobilization of two enzymes (carboxyl esterase and alcohol oxidase) by cross-linking with glutaraldehyde onto PB-Cu carbon paper electrode. A mixture of key aroma ester compounds (methyl butyrate, ethyl butyrate, methyl cinnamate and ethyl cinnamate) was detected in several food samples with low interferences.

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A thick nano-crystalline graphite film (NCG, similar to 350 nm) was grown on dielectric substrate (SiO2, similar to 110 nm) using plasma-enhanced chemical vapour deposition (PECVD) aiming the development of an electrochemical sensor for caffeic acid. The obtained sensor was characterised using several investigation techniques such as atomic force microscopy (AFM), X-ray diffraction (XRD), Raman spectroscopy, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The data evidenced the coexistence in the investigated sample of the nano-crystalline graphite/graphene domains, while the NCG sheet resistance (similar to 340 U/sq.) is matching well the value reported for few-layers graphene film, revealing for the nano-crystalline graphite film a better ordered graphene structure and an improved electrical conduction in the interconnected graphene domains. The sensor for caffeic acid, operating at an applied potential of +0.4 V vs. Hg/Hg2Cl2 reference electrode showed a linear working range comprised between 5.0 X 10(-5) and 1.0 X 10(-3) M, and very good capabilities against real samples analysis. The reproducibility of the developed sensor was assessed in the presence of 0.1mM caffeic acid and the relative standard deviation was 5.84% (n = 11). (c) 2019 Elsevier Ltd. All rights reserved.

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A Si wafer coated with a low temperature oxide (LTO) was used as substrate (Si/SiO2) during the deposition of a thick nano-crystalline graphite (NCG) film by means of plasma-enhanced chemical vapour deposition (PECVD) procedure. The process parameters, the atomic force (AFM) and scanning electron (SEM) micrographs, Raman spectrum and X-ray diffraction (XRD) pattern are herein illustrated. The as deposited NCG film was electrochemically pretreated (3 mA applied current, during 240 s, in 10 mM phosphate buffer saline (PBS) solution containing 0.1 M KCl, pH 7) and thereafter used as electrode for sensing the caffeic acid content in lyophilised berries and dried chokeberries in Nano-crystalline graphite film on SiO2: Electrochemistry and electro-analytical application [1]. (C) 2019 The Author(s). Published by Elsevier Inc.

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This study evaluated the biological activities of Eryngium planum and of Cnicus benedictus extracts enriched in polyphenols obtained by nanofiltration. The HPLC-MS analysis showed that E. planum contains mainly flavonoids, especially rutin, while in C. benedictus extracts show the high concentration of the phenolic acids, principally the chlorogenic acid and sinapic acid. Herein, there is the first report of ursolic acid, genistin, and isorhamnetin in E. planum and C. benedictus. C. benedictus polyphenolic-rich extract showed high scavenging activity (IC50=0.0081 mg/mL) comparable to that of standard compound (ascorbic acid) and a higher reducing power (IC50= 0.082 mg/mL), with IC50 having a significantly lower value than IC50 for ascorbic acid. Both extracts were nontoxic to NCTC cell line. Among the investigated herbs, E. planum polyphenolic-rich extract showed the highest inhibitory activities with the IC50 value of 31.3 g/mL for lipoxygenase and 24.6 g/mL for hyaluronidase. Both polyphenolic-rich extracts had a higher inhibitory effect on -amylase and -glucosidase than that of the acarbose. The synergistic effect of ursolic acid, rutin, chlorogenic acid, rosmarinic acid, genistin, and daidzein identified in polyphenolic-rich extracts could be mainly responsible for the pharmacological potentials of the studied extracts used in managing inflammation and diabetes.

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Mesoporous silica nanoparticles (MSNs) coated with biopolymers are already known for their enormous benefits, as a pharmaceutical matrix, in the medical and pharmaceutical fields. Here, we report the preparation of two types of hybrid matrices, containing SBA-15-MSNs covered with mucilaginous polysaccharides extracted from Althaea officinalis folium in natural and acid pH conditions and polyphenols fraction from Betonica officinalis, respectively. The analysis of phenol composition reveals a selective polysaccharides fraction immobilized on SBA-15-MSNs and evidences higher concentration of polyphenols in Althaeae extract obtained in natural conditions. The acid pH of the extraction conditions favored immobilization of polyphenols on the surface of silica support compared to those obtained under natural conditions. The results regarding the two plant extracts cytotoxicity against the tumour cell line Hep-2 suggest that if Althaeae folium extract is able to reduce the viability of Hep-2 cancer cells likely by reducing the accessibility of the tumour cells to nutrients from the medium, Betonica officinalis extract has the capacity to reduce Hep-2 tumour cell viability by interfering with inner metabolism of the cell. Given these, new effective antiproliferative material biocomposites are expected when combining Althaeae and Betonica extracts.

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The paper presents a study of the phenomena that take place at membrane system interfaces in the process of indole-3-acetic acid (IAA) transport. The results were obtained in a bulk liquid membrane system using trioctylamine, tributylphosphate, trioctilphosphine oxide as carriers in chloroform. The main equilibriums that take place at the interface feed phase% membrane phase were identified and the diffusion coefficient of the indole-3-acetic add complex (DLS) and the extraction constant (Kex) were assessed. The influence of the chemical potential gradient on these parameters was considered.

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Non-nutritive sweeteners represent an ingredient class that directly affects human health, via the development of inflammatory processes that promote chronic diseases related to microbiota dysbiosis. Several in vitro tests were conducted in the static GIS1 simulator. The aim of the study was to highlight the effect of sweeteners on the microbiota pattern of healthy individuals, associated with any alteration in the metabolomic response, through the production of organic acids and ammonium. The immediate effect of the in vitro treatment and the influence of the specific sweetener type on the occurrence of dysbiosis were evaluated by determining the biomarkers of the microbiota response. The presence of the steviol reduced the ammonium level (minimum of 410 mg/L), while the addition of cyclamate and saccharin caused a decrease in the number of microorganisms, in addition to lowering the total quantity of synthesized short-chain fatty acids (SCFAs). The bifidobacteria appeared to decrease below 10(2) genomes/mL in all the analyzed samples at the end of the in vitro simulation period. Barring the in vitro treatment of steviol, all the sweeteners tested exerted a negative influence on the fermentative profile, resulting in a decline in the fermentative processes, a rise in the colonic pH, and uniformity of the SCFA ratio.

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The multiple causes of cardiovascular diseases signify a major incidence and developmental risk of this pathology. One of the processes accountable for this pathologic development is the instauration of dysbiosis and its connection with an inflammatory process. Low antioxidant colonic protection encourages the progression of inflammation, with cardiovascular dysfunctions being a secondary consequence of the dysbiosis. Curcumin is one of the bioactive compounds displaying promising results for the reduction of an inflammatory process. The present study aims at demonstrating the capacity of three extracts drawn from Curcuma (C.) longa through an in vitro simulation process, for microbiota modulation in patients with hypertension. The acidic pH in the extraction process determined a high curcumin content in the extracts. The major phenolic compound identified was curcumin III, 622 +/- 6.88 mu g/mL for the ethanol/water/acetic acid extract. Low EC50 values were associated (0.2 mu g/mL for DPPH scavenging activity) with the presence of curcumin isomers. A metabolic pattern became evident because the relationship between the short-chain fatty acids acted as a clinical biomarker. The curcumin present stimulated the formation of butyric and propionic acids. Microbiota activity control included a high degree of curcumin degradation and biotransformation in the other phenolic compounds. This developmental process was supported by the progression in the enterobacteria with a corresponding escalation in the pH level. The metabolomic pattern demonstrated a performance similar to the administration of dietary fibre, with the positive effects being dose-dependent.

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An interconnected graphene network (IGN) structure with excellent photoluminescence (PL) properties was synthesized using a one-pot microwave-assisted hydrothermal carbonization route. The material exhibited intense and excitation-wavelength dependent PL emission located mainly in the UV-blue light range (300-450 nm). The result demonstrates that graphene networks could also be included in the emerging class of tunable PL carbon nanomaterials. Furthermore, we have taken a first step towards their incorporation into solar cell devices by fabricating IGN/p-SiNWs radial heterojunctions using the versatile potentiostatic electrodeposition technique. The IGN modified p-SiNW solar cell showed the best performance with an overall enhancement of power conversion efficiency of 7.5 times higher than the reference cell. We emphasize that the structural and electronic characteristics of the as-prepared IGN combined with tapering effects are directly responsible for the tripled short circuit current density and 9% improvement of open circuit voltage with respect to the reference cell. Finally, we have demonstrated that the IGN successfully passivated the Si nanowires' surface using intensity modulated photocurrent/photovoltage spectroscopy (IMPS/IMVS). These promising findings indicate that further IGN exploitation may help to gain efficiency in future energy conversion applications.

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In this work we aimed to examine the influence of the main abiotic factors (temperature, rainfall, relative humidity, atmospheric pressure) on the synthesis of active compounds (phenolics, flavonoids), with antioxidant and therapeutic effect of two herbs - Capsella bursa-pastoris (shepherd's purse) and Marrubium vulgare (horehound) collected from two different areas of Romania: Dobrogea (Constanta) and Muntenia (Bucharest). The studies have shown that biogenesis and accumulation of secondary metabolites that gives the therapeutic properties of medicinal plants is influenced by biotic and abiotic factors. In this work we aimed to determine the profile of concentrations of biologically active compounds from the studied herbs depending on the harvest time period and variability of the environmental factors. The medicinal herbs had harvested in autumn (September, 2013) and in spring (May – June, 2014); the alcoholic and aqueous extracts were analyzed in terms of composition: In main biologically active compounds (phenolics, flavonoids) and antioxidant activity as DPPH and ABTS, and spectral data analysis by FTIR. Experimental data obtained showed a significantly higher phenolics and flavonoids content and also a higher antioxidant activity in herbs harvested from the Dobrogea (Constanta) area, for the herbs studied. © 2019, Gheorghe Asachi Technical University of Iasi, Romania. All rights reserved.

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A thick nano-crystalline graphite film (NCG, ∼350 nm) was grown on dielectric substrate (SiO 2 , ∼110 nm) using plasma-enhanced chemical vapour deposition (PECVD) aiming the development of an electrochemical sensor for caffeic acid. The obtained sensor was characterised using several investigation techniques such as atomic force microscopy (AFM), X-ray diffraction (XRD), Raman spectroscopy, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The data evidenced the coexistence in the investigated sample of the nano-crystalline graphite/graphene domains, while the NCG sheet resistance (∼340 Ω/sq.) is matching well the value reported for few-layers graphene film, revealing for the nano-crystalline graphite film a better ordered graphene structure and an improved electrical conduction in the interconnected graphene domains. The sensor for caffeic acid, operating at an applied potential of +0.4 V vs. Hg/Hg 2 Cl 2 reference electrode showed a linear working range comprised between 5.0 × 10 −5 and 1.0 × 10 −3 M, and very good capabilities against real samples analysis. The reproducibility of the developed sensor was assessed in the presence of 0.1 mM caffeic acid and the relative standard deviation was 5.84% (n = 11). © 2019 Elsevier Ltd

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The intensive use of toxic and remanent pesticides in agriculture has prompted research into novel performant, yet cost-effective and fast analytical tools to control the pesticide residue levels in the environment and food. In this context, biosensors based on enzyme inhibition have been proposed as adequate analytical devices with the added advantage of using the toxicity of pesticides for detection purposes, being more biologically relevant than standard chromatographic methods. This review proposes an overview of recent advances in the development of biosensors exploiting the inhibition of cholinesterases, photosynthetic system II, alkaline phosphatase, cytochrome P450A1, peroxidase, tyrosinase, laccase, urease, and aldehyde dehydrogenase. While various strategies have been employed to detect pesticides from different classes (organophosphates, carbamates, dithiocarbamates, triazines, phenylureas, diazines, or phenols), the number of practical applications and the variety of environmental and food samples tested remains limited. Recent advances focus on enhancing the sensitivity and selectivity by using nanomaterials in the sensor assembly and novel mutant enzymes in array-type sensor formats in combination with chemometric methods for data analysis. The progress in the development of solar cells enriched the possibilities for efficient wiring of photosynthetic enzymes on different surfaces, opening new avenues for development of biosensors for photosynthesis-inhibiting herbicides.

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Acrylamide (AA) is a toxic compound formed in thermally prepared foods by Maillard reaction. Besides foods, AA may be found in cosmetic products as an impurity of the widely-used non-toxic polyacrylamide. We present a novel, fast and selective detection method based on the amperometric monitoring of the coupling reaction between reduced glutathione (GSH) and AA catalyzed by glutathione S-transferase (GST) to produce an electrochemically inactive compound. We have used electrodes modified with cobalt-phthalocyanine to monitor the decrease of GHS concentration at +300 mV. Our system is simple, does not require supplementary substrates such as 1-chloro-2,4-dinitrobenzene (CDNB) nor have disadvantageous competitive kinetics characteristic to inhibition like signals. Using the optimum concentration of 100 M GSH we have obtained a linear calibration graph from 7 to 50 M AA and a limit of detection of 5 M AA. The method is not affected by interfering compounds usually found in foods and was applied for real sample analysis.

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The electrochemical behaviour of the flavonoid naringenin (NGN) was investigated for the first time by cyclic voltammetry (CV), using a disposable electroactivated pencil graphite electrode (PGE*). In this electrochemical sensor, NGN is irreversibly oxidized, giving rise to two pH-dependent peaks due to mixed (diffusion- and adsorption-controlled) electrode processes involving the same number of electrons and protons, namely two and one, respectively. Exploiting these peaks, differential pulse voltammetry (DPV) and square wave voltammetry (SWV) at PGE* in 0.05 mol L-1 potassium hydrogen phthalate were applied for quantitative determination of NGN. The new proposed methods presented linear ranges covering more than three orders of magnitude (7.86 x 10(-8) to 1.82 x 10(-4) mol L-1 NGN for DPV and 7.50 x 10(-8) to 1.00 x 10(-4) mol L-1 NGN for SWV) and low limits of detection (LoD) and quantification (LoQ) (LoD = 3.06 x 10(-8) mol L-1, LoQ = 1.02 x 10(-7) mol L-1 NGN for DPV and LoD = 4.40 x 10(-8) mol L-1, LoQ = 1.11 x 10(-7) mol L-1 NGN for SWV), similar to or better than those reported in the literature. The developed voltammetric methods were applied with good results to determine the intermediate antioxidant power polyphenolics content expressed as mg naringenin equivalent per L grapefruit juice.

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It is well known that the secretion of melatonin begins after the first months of life and is necessary to be supplied through mother's milk or infant formula. It is also important to know the concentrations of compounds involved in the synthesis of melatonin in the pineal gland from the composition of infant formula. Therefore, an HPLC method with UV and fluorescence detection was developed which enables the simultaneous determination of melatonin, serotonin, L-tryptophan, and vitamins B-3 and B-6 in 30 min. The chromatographic method was validated in terms of selectivity, linearity range of the response (R > 0.9997), detection limit (0.0011-0.01 mg L-1), limit of quantitation, precision, accuracy, and robustness and has been proved that it may be used as a tool for evaluating these compounds in infant formulas and also in the manufacture of baby foods. The chromatographic method was applied for the quantification of analytes of interest and for the first time, it has proven the existence of melatonin (0.00045-0.00824 mg/g) and serotonin (0.00002-0.00056 mg/g) in infant formulas from birth onwards.

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Background: In the last years, the production and applications of nanoparticles based on iron oxides in the field of biomedicine presented a great interest due to their particular properties. Because of the expansion of the pharmaceutical industry numerous new systems for drugs delivery have appeared, and those centered on magnetic nanoparticles are in a particular attention and in different promising developmental stages. Objective: In this mini review, some representative, interesting and feasible magnetic nanostructures obtained recently (from last 5-6 years) with possible use in antitumor/anticancer therapy are presented. Results: The synthesis of these nanostructures with magnetic properties implies very simple assembling procedures and presents one of the lowest cytotoxic profiles. Magnetic nanostructures displayed possible appliance in a large diversity of biotechnological and medical fields, both for diagnose and therapy. Conclusion: Different types of magnetic nano-carriers loaded with different antitumor/ anticancer agents and the cases tested in vivo are considered.

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This work presents the efficacy of various green extraction methods used to ensure the optimal amount of antioxidant compounds extracted from vegetal material. The new developed extraction procedures are easy-to-use and have a low implementation cost providing health-safe and high-quality extracts (products). The complete characterization of the obtained extracts was performed by a HPLC method (quantification of antioxidant compounds) and the ORAC method (efficacy assessment). These methodologies have high potential in by-products industry, where managing the residues is an important step in increasing the technological process economic efficiency and mitigation of environmental impact and, moreover, can by further extended to other types of raw materials.

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This study presents the effect of two new products based on atomized extracts from edible wild mushrooms (RoBioMush1, RoBioMush2) on the microbiota of three target groups: clinically healthy (NG) individuals, individuals with nutritional disorders (ND), and individuals with cardiovascular diseases (CVD). The microbiota fingerprints were determined by quantitative polymerase chain reaction (qPCR). Modulations in the simulated microbiome were established and correlated with the presence of phenolic compounds released in the in vitro environment (a three-stage culture system GIS2 simulator, www.gissystems.ro). The high metabolizing capacity of NG and CVD correlated positively with the rest of the biological activities expressed in vitro. ND microbiota consumed a wide spectrum of monosaccharides from the products. Xylose was present in large quantities in the descending segment (minimum: 175 mu g/mL for ND). The primary conclusion was that the microbiological ecosystem was modulated, as proven by the presence of specific biomarkers (e.g., ammonium levels and fingerprints of short-chain fatty acids-SCFAs), which stimulate the organism's health status and were correlated with the restoration of a normal microbiota fingerprint.

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Berteroa incana is a wild herb widespread in temperate zones which was practically not studied for its biological effects. Methanolic and aqueous extracts of B. incana were assessed for the content in polyphenols and the related antioxidant and antimicrobial activities and the polysaccharide extract for the content in saccharides and the associated cytostatic effect. The results obtained highlighted that the methanolic extracts of B. incana contain moderate amounts of polyphenols, the most representative been isoquercitrin 4.41 +/- 0.02 mg100 g(-1)dry weight plant material (DW), quercetin 4.21 +/- 0.05, sinapic acid 5.23 +/- 0.12 and ferulic acid 5.05 +/- 0.12 mg 100 g(-1)DW, with correlated moderate antioxidant activities (IC (50) 13.40 +/- 0.01 mu g mL(-1)) and absent antibacterial activity. The polysaccharide fraction showed high content in saccharides, especially in arabinose (312.22 +/- 7.54 mg g(-1) polysaccharide extract) and glucose (279.22 +/- 5.59), and promising cytostatic effect. [GRAPHICS] .

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The challenge for conformal modification of the ultra-high internal surface of nanoporous silicon was tackled by electrochemical polymerisation of 2,6-dihydroxynaphtha lene using cyclic voltammetry or potentiometry and, notably, after the thermal treatment (800 degrees C, N-2, 4 h) an assembly of interconnected networks of graphene strongly adhering to nanoporous silicon matrix resulted. Herein we demonstrate the achievement of an easy scalable technology for solid state supercapacitors on silicon, with excellent electrochemical properties. Accordingly, our symmetric supercapacitors (SSC) showed remarkable performance characteristics, comparable to many of the best high-power and/ or high-energy carbon-based supercapacitors, their figures of merit matching under battery-like supercapacitor behaviour. Furthermore, the devices displayed high specific capacity values along with enhanced capacity retention even at ultra-high rates for voltage sweep, 5V/s, or discharge current density, 100 A/g, respectively. The cycling stability tests performed at relatively high discharge current density of 10 A/g indicated good capacity retention, with a superior performance demonstrated for the electrodes obtained under cyclic voltammetry approach, which may be ascribed on the one hand to a better coverage of the porous silicon substrate and, on the other hand, to an improved resilience of the hybrid electrode to pore clogging.

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The electrochemical behaviour of the flavonoid naringenin (NGN) was investigated for the first time by cyclic voltammetry (CV), using a disposable electroactivated pencil graphite electrode (PGE∗). In this electrochemical sensor, NGN is irreversibly oxidized, giving rise to two pH-dependent peaks due to mixed (diffusion- and adsorption-controlled) electrode processes involving the same number of electrons and protons, namely two and one, respectively. Exploiting these peaks, differential pulse voltammetry (DPV) and square wave voltammetry (SWV) at PGE∗ in 0.05 mol L -1 potassium hydrogen phthalate were applied for quantitative determination of NGN. The new proposed methods presented linear ranges covering more than three orders of magnitude (7.86 × 10 -8 to 1.82 × 10 -4 mol L -1 NGN for DPV and 7.50 × 10 -8 to 1.00 × 10 -4 mol L -1 NGN for SWV) and low limits of detection (LoD) and quantification (LoQ) (LoD = 3.06 × 10 -8 mol L -1 , LoQ = 1.02 × 10 -7 mol L -1 NGN for DPV and LoD = 4.40 × 10 -8 mol L -1 , LoQ = 1.11 × 10 -7 mol L -1 NGN for SWV), similar to or better than those reported in the literature. The developed voltammetric methods were applied with good results to determine the intermediate antioxidant power polyphenolics content expressed as mg naringenin equivalent per L grapefruit juice. © 2018 The Royal Society of Chemistry.

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In this study several investigations and tests were performed to determine the antioxidant activity and the acetylcholinesterase and tyrosinase inhibitory potential of Pulmonaria officinalis and Centarium umbellatum aqueous extracts (10% mass) and ethanolic extracts (10% mass and 70% ethanol), respectively. Moreover, for each type of the prepared extracts of P. officinalis and of C. umbellatum the content in the biologically active compounds – polyphenols, flavones and proanthocyanidins was determined. The antioxidant activity was assessed using two methods, namely the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and reducing power assay. The analyzed plant extracts showed a high acetylcholinesterase and tyrosinase inhibitory activity in the range of 72.24–94.24% (at the highest used dose – 3 mg/mL), 66.96% and 94.03% (at 3 mg/mL), respectively correlated with a high DPPH radical inhibition – 70.29–84.9% (at 3 mg/mL). These medicinal plants could provide a potential natural source of bioactive compounds and could be beneficial to the human health, especially in the neurodegenerative disorders and as sources of natural antioxidants in food industry. © 2016

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A 120 kilometers reach of the Prut River, Romania was surveyed and the concentrations of four trace metals (copper, cadmium, lead and zinc) were determined in water and sediments. These elements are the main pollutants expected in the region, as a steel-producing factory in Romania is located in the close neighborhood of an area under protection, the Lower Prut Floodplain Natural Park. Samples were collected in 2010 and 2011 from the water-sediment interface at six locations along the lower sector of the Prut River. Sediments were sampled only once whereas water samples were collected during four campaigns organized at the end of the summer and beginning of the autumn in order to include both high and low flow regimes of the river. Toxic metals (Pb and Cd) were not found to reach notable levels. The resulted concentrations for all trace metals were lower than the values determined in other Romanian rivers (e.g. Danube) and within the values range imposed by the Romanian regulations for water and sediments quality. © 2018, Gheorghe Asachi Technical University of Iasi, Romania. All rights reserved.

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Acrylamide (AA) is a toxic compound formed in thermally prepared foods by Maillard reaction. Besides foods, AA may be found in cosmetic products as an impurity of the widely-used non-toxic polyacrylamide. We present a novel, fast and selective detection method based on the amperometric monitoring of the coupling reaction between reduced glutathione (GSH) and AA catalyzed by glutathione S-transferase (GST) to produce an electrochemically inactive compound. We have used electrodes modified with cobalt-phthalocyanine to monitor the decrease of GHS concentration at +300 mV. Our system is simple, does not require supplementary substrates such as 1-chloro-2,4-dinitrobenzene (CDNB) nor have disadvantageous competitive kinetics characteristic to inhibition like signals. Using the optimum concentration of 100 μM GSH we have obtained a linear calibration graph from 7 to 50 μM AA and a limit of detection of 5 μM AA. The method is not affected by interfering compounds usually found in foods and was applied for real sample analysis. © 2018 The Royal Society of Chemistry.

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A Sense and Control Circuit (SCC) developed for amperometric concentration evaluation is redesigned, based on preliminary experimental investigations. This cost-effective circuit comprises a potentiostat for three-electrode electrochemical cell (biosensor) control and a transimpedance amplifier for cell current sensing. Stability, noise robustness and response time are improved, as demonstrated by experiments and simulations. SCC performances are evaluated in comparison with a professional system, by H2O2 concentration measurements.

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Copper substrates deposed on a gold screen-printed electrodewere coveredwith different aryl diazonium salts by electrodeposition at 0.25 mA for 30 or 300 s. Seven compounds were investigated: 4-aminophenylacetic acid, 4-aminophenethyl alcohol, 4-fluoroaniline, 4-(heptadecafluorooctyl) aniline, 4-aminoantipyrine, 4-(4-aminophenyl) butyric acid and 3,4,5-trimethoxyaniline. Quantitative monitoring of the electrodeposition process was carried out by electrogravimetry using quartz crystal microbalance (QCM). The electrodeposited mass varies between 26 ng/cm(2) for 4-fluoroaniline formed during 30 s to 442 ng/cm(2) for 4-phenylbutyric acid formed during 300 s. The corrosion inhibition properties of aryl-modified layers have been studied in buffer citrate with pH = 3 or 3.5% NaCl solutions using electrochemical noise (ECN) and Tafel potentiodynamic polarization measurements. A corrosion inhibiting efficiency up to 90% was found. The highest corrosion inhibition was obtained for 4-(4-aminophenyl) butyric acid and the lowest for 4-fluoroaniline. A relation between the inhibition efficiency and the chemical nature of the substituents in the protective layer was found.

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The goal of the present work was to study the influence of winemaking procedures and the effect of bottle-aging on the antioxidant activity and on the variation of low molecular weight phenolics of Feteasca Neagra and Negru Aromat red wine from the Valea Calugareasca vineyard, Romania. The free radical-scavenging activity was measured using the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical from bottles sampled every 3 months up to the 9th month. The results indicated that Negru Aromat obtained by classical maceration had the highest activity at 6th month. The highperformance liquid chromatography results showed that the most abundant low molecular weight phenolic compounds were catechin, (-)-epicatechin, gallic acid, malvidin, and peonidin 3-O-glucoside. For the phenolics, Feteasca Neagra prepared by classical maceration and Negru Aromat by run-off juice were the richest. For anthocyanidins, the Feteasca Neagra and Negru Aromat wine by classical maceration had the highest concentrations. These results suggest that classical maceration is the winemaking procedure of choice to obtain the highest quality wine from the Valea Calugareasca vineyard.

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In the present study the antioxidant and cytostatic capacities of some 8% Geranium robertianum (geranium) aqueous extracts processed by membrane procedures (micro- and ultrafiltration) were determined. The extracts were purified by microfiltration and then concentrated by successive ultrafiltrations using Millipore membranes with 10,000 and 1000 Da cut-off. Two methods were used to establish the extracts' antioxidant activity: DPPH and ABTS; the cytostatic capacity was evaluated on HEp-2p cell lines, by a qualitative method (cytochemical stain with Giemsa solution) and quantitative one (MTT test). Four concentrations of Geranium aqueous extracts were used to test cell viability: 100, 500, 1000 and 2000 mu g/mL, 24 and 48 h, against the control culture (100% viability). The concentrated samples had the highest content of total polyphenols and the strongest antioxidant effect, having also the biggest impact upon cell viability. (C) 2013 Production and hosting by Elsevier B.V. on behalf of King Saud University.

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Background: Arum hygrophilum is a traditional medicinal plant indigenous to Jordan. The present study explores its phytochemistry, antioxidative, antidiabesity, and antiproliferative potentialities. Materials and Methods: Column chromatography and HPLC-MS analysis were used for its phytochemical evaluation. Using leaf crude water and ethanol extracts, the antioxidative capacities, their modulation of pancreatic beta-cell proliferation, and insulin secretion as well as glucose diffusion and enzymatic bioassays were evaluated. Results: Three flavonoids (luteolin, isoorientin, and vitexin) and beta-sitosterol have been isolated and their structures determined. HPLC-MS analysis of the ethanol extract further revealed the presence of caffeic, ferulic, gallic, and rosmarinic acids and quercetine-3-O-rhamnoside. The ethanol extract exhibited DPPH and ABTS radical scavenging and antioxidative capacities. A. hygrophilum (1), vitexin (2), and rosmarinic acid (3) inhibited pancreatic lipase (PL) dose dependently with PL-IC50 (mu g/ mL) values in an ascending order: (3); 51.28 +/- 7.55 < (2); 260.9 +/- 21.1 < (1); 1720 +/- 10. Comparable to GLP-1-enhanced beta-cell proliferation in 2-day treatment wells, a dose-dependent augmentation of BrdU incorporation was obtained with the A. hygrophilum aqueous extract (AE) (0.5 and 1 mg/ mL, with respective 1.33-and 1.41-folds, P < 0.001). A. hygrophilum AE was identified as an inhibitor of alpha-amylase/alpha-glucosidase with IC50 value of 30.5 +/- 2.1 mg/mL but lacked antiproliferative effects in colorectal cancer cell lines (HT29, HCT116, and SW620) and insulinotropic effects in beta-cell line MIN6. Conclusion: A. hygrophilum extracts inhibited gastrointestinal enzymes involved in carbohydrate and lipid digestion and absorption.

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Polysaccharides display several biological activities, such as antitumour, anti-oxidation, hypoglycaemic, antiviral and immunity enhancing properties. The polysaccharide fraction from Phemeranthus confertiflorus was extracted, hydrolysed and 8 monosaccharides were analysed and quantified by capillary electrophoresis. The polysaccharide fraction was further assessed for cytotoxicity on normal and tumour cell lines. The results obtained can promote Phemeranthus as an eligible plant with potential for human health, because of high monosaccharides content (predominant rhamnose) and promising cytostatic effect of polysaccharide fraction.

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A fast separation method for simultaneous determination of eleven organic acids was validated and applied to different commercial food items to evaluate their organic acids content. The present method gives detection limits between 0.04 and 4.65 mu g mL(-1), recovery values in real samples between 78.2 and 97.3% and relative standard deviation values for precision lower than 5%. All validation data were in acceptable range and prove the method's fit for purpose. The advantages of the method are the short runtime analysis (15 min), no preparation step for the samples before the injection combined with good sensitivity which recommends it for routine control analysis in food industries. Moreover, this methodology has high potential in drinks industry but can by further extended to other types of food items.

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Novel molecularly imprinted polymers (MIPs) designated for the solid-phase extraction of antibiotics containing a 5-nitrofuran ring (nitrofurantoin and furaltadone) are reported. The synthesis of these MIPs was based on commercial monomers and cross-linking agents capable of forming hydrogen bonds with the template molecules. Thus, the designed MIPs should involve acceptable costs and easier accessibility. Their retention properties were studied by solid-phase extraction (SPE) procedures and the breakthrough curves were evaluated for both imprinted and non-imprinted polymers (NIPs). Due to the presence of adsorption sites created in polymers by imprinting, the MIPs showed a significant difference in the retention property in comparison to NIPs. The MIPs were also immobilized onto a gold electrode surface by entrapment into a silane sol-gel matrix for the development of a sensor based on electrochemical impedance measurements. The good mechanical adherence of the sol-gel matrix on the gold electrode surface was achieved by formation of a self-assembled monolayer using 3-mercaptopropyl trimethoxisilane that acts as an anchoring bridge.

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Propolis, a known bee product for its beneficial effects on the human health, was the focus of many investigations recently carried out. In the present study we evaluated antioxidant and antifungal activity of propolis fractions and ethanolic extracts of propolis (EEP) from different regions of Romania. The evaluation of the antimicrobial activity of propolis samples was performed by an adapted disc diffusion and serial microdilutions methods. The EEP influence on biofilm development on the inert substratum was investigated by the microtiter method. The antioxidant activity was evaluated using the free radicals1,1-diphenyl-2-picryl-hydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) scavenging methods. The propolis fractions and EEPs used in this study exhibited antifungal and antibiofilm activity against all tested Candida albicans strains and revealed a strong free radical scavenging capacity. These results recommend Romanian propolis as a natural antioxidant and a potential therapeutic agent useful in the prevention and therapy of oxidation-related diseases and Candida albicans infections. An updated data analysis in the changing foodborne pathogens evolution in Romania and improvements in food chain traceability.

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Therapeutic benefits of phytochemicals are widespread, but the association of natural lipophilic and hydrophilic compounds in the same nanostructured delivery system represents a challenge that was not considered up to present. This work aimed to evaluate the effects of two plant-derived oils rich in omega-3 (rosehip oil Ro) and omega-6 (black caraway oil Bco) on the synthesis of marigold extract (ME) and azelaic acid (AzA) co -loaded nanostructured lipid carriers(NLC) and to determine its in vitro and in vivo anti-inflammatory action. The lipid core and surfactant shell guaranteed a high encapsulation efficiency of both water soluble -AM and lipid soluble -ME(93% entrapment for carotenoids and 83% for AM). A high degree of biocompatibility in the concentration range of 5-400 mu g/mL NLC-ME-AzA for 72 h of treatment was determined (i.e. at 400 mu g/mL the L929 cells displayed a proliferative effect with a cell viability of 110%). The co-presence of ME and AM in the same NLC was accompanied by a reduced expression of inflammatory IL-6 and IL-1 beta cytokines, as evidenced by ELISA method. The in vivo plestismometric method showed that paw edema was significantly reduced for 3 h following NLC-ME-AzA hydrogel treatment (0.006 mg ME and 26.2 mg AAz) in rats challenged with carrageenan.

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Portulaca pilosa L and Portulaca oleracea L were comparatively studied for the total content of polyphenols and flavonoids, antioxidant activity, individual polyphenols, short-chain organic acids, and saccharides in extracts of plants collected from Bucharest ''delta'' using spectrometry and capillary electrophoresis. The polysaccharide fractions were assessed for cytotoxicity on normal and tumor cell lines. The results obtained highlighted that Portulaca pilosa could be considered more valuable than Portulaca oleracea because of its higher content in important flavonoids (quercetin 101.70 +/- 2.68 mu g g(-1) dry weight plant material, rutin 96.24 +/- 0.74 mu g g(-1) DW plant material) and some phenolic acids (chlorogenic acid 161.33 +/- 0.67 mu g g(-1) DW plant material, p-coumaric acid 61.40 +/- 5.50 mu g g(-1) DW plant material) of the ethanolic extracts, for its lower content in oxalic acid that is considered anti-nutrient of the aqueous extracts, and for its higher content in saccharides, especially rhamnose and xylose, with consequently higher cytostatic effect of the polysaccharide fraction. The current study presented for the first time the content in polyphenols, short chain organic acids, and saccharides of Portulaca pilosa and proved that this species has noticeable antioxidant activity, low toxicity on normal cells, and high toxicity on tumor cells and could be considered important for health and food industry.

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Some aspects of the chemical composition were studied in extracts of unexplored Phemeranthus confertiflorus L, an alien plant collected from Bucharest delta. 16 polyphenols and 10 short-chain organic acids were analysed and quantified by capillary electrophoresis in Phemeranthus extracts and antioxidant activity was investigated. The results obtained could promote Phemeranthus as an eligible plant with potential in food industry and for human health, because of the high antioxidant activity, high content of flavonoids (naringenin, rutin, daidzin) and lactic acid.

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Indole-3-acetic acid is a growth phytohormone considered the most important representative of auxin class. This paper presents the assessment of some kinetic parameters in the process of transport of indole3-acetic acid taking into consideration the kinetic model of consecutive irreversible first order reactions. It was pursued the influence upon the process of parameters such as: feed phase concentration, stripping phase concentration in the presence of two type carriers: tributyl phosphate (TBP) and trioctylphosphine oxide (TOM), Depending on these transport parameters were calculated kinetics parameters such as: pseudo-first-order apparent membrane entrance and exit rate constants, the maximum flux at the entrance and exit out of the membrane. The highest values of the transport flux is obtained in the presence of carrier trioctylphosphine oxide (TOPO) at the concentration in the feed phase of 10(-4) indole-3-acetic acid and a concentration of 10(-2) moUL NaOH in the stripping phase.

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An optical/amperometric biosensor based on algal cells immobilized in calcium alginate gel was developed. Various Chlamydomonas reinhardtii strains mutated at the level of photosynthetic D1 protein were used as biomediators to quantify the capacity of the carotenoid xanthophylls to protect the photosynthetic apparatus from photoinhibition. The highly sensitive/selective biosensor was used for studies on cell physiology aimed to determine the antioxidant and light filtering effects of the xanthophyll astaxanthin. The biosensor was proved to be suitable for the determination of the exogenous supplied astaxanthin, showing in a short time a reliable response with a detection limit of 3 mu M. This technique revealed the photoprotective effect of astaxanthin-enriched extracts of Haematococcus pluvialis in algal cells. The results suggest that in algae astaxanthin exploits both filtering and antioxidant effects at different light intensities. This bioinspired approach can provide new insights into biological, biomedical, environmental and agricultural research applications and nutraceutical studies. (C) 2016 Elsevier B.V. All rights reserved.

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The objectives of this study were to define the phenolic profile, antioxidant, antimicrobial and anti-inflammatory properties of extracts from Betonica officinalis and Salvia officinalis herbs used in traditional medicine. The results indicated that the extract inhibits scavenges stable 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radicals. In the present study, Salvia officinalis was potent antibacterial agent against Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa. The extracts inhibited cyclooxygenase (COX-1) and denaturation of protein, which suggests these species might be a potential source of plant-derived anti-inflammatory substances. Our study, for the first time, revealed the antimicrobial and anti-inflammatory activity of the Betonica officinalis herb. The results of this study could be helpful to develop medicinal preparations and uses of this species as an antimicrobial, anti-inflammatory and wound healing agent.

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Frequent occurrence of food contamination, growing concern about public safety, and the adoption of more stringent legislations have promoted research efforts in the agrifood industry as well as in environmental monitoring, attempting to guarantee improvements in food quality and safety. In addition, the increasing demand for sustainable agriculture has led to the introduction of novel processing methods for raw materials to achieve stable foods. For this reason, it is imperative that efficient and reliable diagnostic tools be developed to detect potential hazards in agriculture and for food safety. In this context, biosensor technology represents the cutting -edge frontier in the agrifood and environmental fields. Indeed, smart monitoring of chemical contaminants (i.e., pesticides, heavy metals, toxins, allergenic compounds, and food additives) represents one of the evolving issues challenging the assessment of food quality and safely. Progress in multianalyte screening, functional materials, microlluidics and nanotechnology is amplifying the potential market of biosensors, making this technology more competitive in comparison with conventional lab -based procedures in terms of speed of response and operational held usage. However, despite the large number of publications and patents on biosensors for food analysis, only a few systems have been able to reach the market. Among the main drawbacks to he faced are the limited lifetime of biological components, mass production, as well as portability. In this chapter, current and future trends in analytical diagnostic tools are discussed, with the aim of promoting a deeper cooperation between research and industries and encouraging the use of biosensing technology as a more attractive option for the commercial sector.

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A low-interferences enzymatic sensor for evaluating the antioxidant capacity was developed. Xanthine oxidase was used to produce superoxide radicals that spontaneously dismutate to hydrogen peroxide. Low xanthine concentrations were used to minimize the rapid dismutation of the superoxide radical before its fast reaction with antioxidants. The sensor operates in the reduction mode, and evaluations with low interferences of the antioxidant capacity are based on the detection of remaining hydrogen peroxide using Prussian blue electrodes at low potentials. The linear calibration graph is between 2 - 10 mu M ascorbic acid. No interferences were observed from easily oxidisable substances including uric acid, which is produced in the enzymatic reaction or other substances usually found in foods. The method was used to evaluate the antioxidant capacity in different real juice samples.

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Prussian blue modified with copper was electrodeposited on a platinum microelectrode for the amperometric determination of hydrogen peroxide at -50 mV. The Prussian blue-copper layer was stable for 2 h at pH 7.4 and a storage period of 2 months. The Prussian blue-copper modified microelectrodes were used to develop oxidase based microbiosensors for ethanol and lactate. Lactate and alcohol oxidases were immobilized by cross-linking with glutaraldehyde. No interferences were observed from possible interfering compounds up to a concentration of 0.5 mM. The calibration plot of the lactate microbiosensor was linear between 0.005 and 0.2 mM with a limit of detection of 0.0035 mM lactate. The linear dynamic range of the alcohol microbiosensor was between 0.05 and 2 mM and the limit of detection was 0.02 mM ethanol. The developed microbiosensors were used for the analysis of pickled cucumber juice, yogurt, and wine.

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The quality of red wines is given by phenolic compounds and anthocyanins and is associated with colour, taste and therapeutic effects on human health. This work aims to provide a detailed profile of phenolic compounds and anthocyanins that are found in five red wine samples from Dealu Mare-Valea Calugareasca region. The phenolic and anthocyanin profiles of the red wine samples were determined by high-performance liquid chromatography-photodiode array-mass spectrometry and matrix-assisted laser desorption/ionisation-time of flight, respectively. The results obtained showed that Feteasca Neagra had the highest content of phenolic compounds followed by Pinot Noir while the preponderant compound was gallic acid. Amongst anthocyanins, malvidin was found to be the major compound and the highest anthocyanin content was found also for Feteasca Neagra wine. A simple high-performance liquid chromatography-photodiode array-mass spectrometry method was developed, optimised and applied for the quantification of phenolic compounds in red wine samples from Dealu Mare-Valea Calugareasca region. In the same time, a rapid matrix-assisted laser desorption/ionisation-time of flight method that does not need sample preparation was applied for the identification of anthocyanins. Moreover, the phenolic and anthocyanin composition of red wines from Dealu Mare-Valea Calugareasca region is reported for the first time. The phenolic and anthocyanin profile determination will be beneficial for the Romanian winemakers to produce high-quality red wines.

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The growing scientific interest in exploitation of vegetable bioactives has raised a number of questions regarding their imminent presence in pharmaceutical formulations. This study intends to demonstrate that a dual combination between vegetable oil (e.g. thistle oil, safflower oil, sea buckthorn oil) and a carrot extract represents an optimal approach to formulate safe carrier systems that manifest cell regeneration effect and promising antioxidant and anti-inflammatory activity. Inclusion of both natural actives into lipid carriers imparted a strong negative charge on the nanocarrier surface (up to -45 mV) and displayed average sizes of 70 nm to 140 nm. The entrapment efficiency of carrot extract into nanostructured carriers ranged between 78.3 and 88.3%. The in vitro release study has demonstrated that the entrapment of the extract represents a viable way for an equilibrated release of carotenoids. Besides the excellent antioxidant properties (e.g. scavenging up to 98% of the free oxygen radicals), the results of cellular integrity (e.g. cell viability of 133%) recommend these nanocarriers based on dual carrot extract-bioactive oil as a promising trend for the treatment of certain disorders in which oxidative stress plays a prominent role. In addition, the lipid nanocarriers based on safflower oil and sea buckthorn oil demonstrated an anti-inflammatory effect on LPS induced THP-1 macrophages, by inhibiting the secretion of two pro inflammatory cytokines, IL-6 and TNF-alpha. (C) 2016 Elsevier B.V. All rights reserved.

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In the current work, ethanol and water extracts of Verbascum phlomoides and Solidago virgaureae were examined for their inhibitory effects against acetylcholinesterase and tyrosinase, as well as for their antioxidant activity. The antioxidant activity was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and a reducing power assay. The total content of phenolics, flavonoids and proanthocyanidins, and the high-performance liquid chromatography profile of the main phenolic compounds were also determined. Generally, ethanol extracts showed the strongest antioxidant and enzyme inhibitory activities, both of which were related to the total phenolic content. The V. phlomoides ethanol extract showed the highest inhibitory activity against both acetylcholinesterase (IC50= 0.086 +/- 0.005 mg/mL) and tyrosinase (IC50= 0.109 +/- 0.092 mg/mL). These results reveal that V. phlomoides and S. virgaureae are potential sources of active metabolites with acetylcholinesterase and tyrosinase inhibitory effects. As a result they could be considered for dietary food supplements for preventing neurodegenerative diseases. (C) 2016 Elsevier GmbH. All rights reserved.

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The aim of this study was to investigate the antioxidant, anti-amylase and anti-glucosidase activities of polyphenolic-rich extracts from Betonica officinalis and Impatiens noli-tangere and to analyze their chemical composition by HPLC-MS. Hydro-alcoholic extracts of the two medicinal herbs were processed by microfiltration and ultrafiltration for concentrating the polyphenolic compounds. Phenolic acid, mainly chlorogenic acid and caffeic acid were the dominant compounds of B. officinalis extracts, while the extracts from L nolitangere contain mainly flavonoids, especially isoquercitrin. The polyphenolic-rich extract (retentate UF fraction) from B. officinalis exhibited the most potent DPPH radical scavenging and reducing power activities. The IC50 value of the alpha-amylase inhibitory effect was 4.20 +/- 0.30 mg/mL for the B. officinalis polyphenolic-rich extract, slightly higher than that of I. noli-tangere polyphenolic-rich extract of 4.01 +/- 0.25 mg/mL. The polyphenolic-rich extract from I. noli-tangere showed remarkable a-glucosidase inhibition activity (IC50 0.47 +/- 0.02 mg/mL), compared to the acarbose (IC50 0.38 +/- 0.02 mg/mL). However, I. noli-tangere extracts displayed a stronger inhibitory activity than B. officinalis extract fractions. Our study, for the first time, revealed the anti-diabetic potential of the B. officinalis and I. noli-tangere herbs. The results of this study could be helpful to develop medicinal preparations or functional foods for diabetes. (C) 2015 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

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The electrophoretic method partially validated for separation and quantification of 16 polyphenols from aqueous and ethanolic extracts of Calendula officinalis, Hypericum perforatum, Galium verum and Origanum vulgare in 27 min showed good efficiency and precision, and low detection and quantification limits (between 0.06 - 1.38 mu g mL(-1) and 0.2 - 4.56 mu g mL(-1), respectively). Correlation coefficients (r(2)) exceed 0.994 and recovery values ranged between 86.66 and 101.54 %. Under these conditions the developed electrophoretic method would be suitable for the analysis of various extracts.

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The matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF) and micellar electrokinetic chromatography (MEKC) methods were used to identify and quantify five tannins, (+)-catechin, (-)-epigallocatechin, (-)-epigallocatechin gallate, (-)-epicatechin gallate and (-)-epicatechin, from aqueous, ethanolic and acetonic extracts of Calendula officinalis, Hypericum perforatum, Galium verum and Origanum vulgare. The MALDI-TOF technique was used for screening tannins monomers and oligomers in plant extracts. The sandwich method and matrix 2,5-dihydroxybenzoic acid with a concentration of 10 mg mL(-1) in acetonitrile/ultrapure water/trifluoroacetic acid (20 : 80 : 0.1, vol.) were used. The electrophoretic method developed for the separation and quantification of 5 catechins in 15 min exhibited good efficiency and precision, low limits of detection (0.0032-0.0153 mu g mL(-1)) and quantification (0.0096-0.0466 mu g mL(-1)). The correlation coefficients (R-2) exceeded 0.9986 and the recovery values ranged between 94.25 % and 102.50 %. The present work provides new information on some of the less studied compounds present in plants frequently used in traditional medicine. (C) 2015 Institute of Chemistry, Slovak Academy of Sciences

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It is studied a batch analytical method based on the system Co(II)EDTA/luminol/H2O2 for the determination of antioxidant capacity of different types of sample. The method is based on the oxidation and chemiluminescence of luminol under the influence of reactive oxygen species produced in a Fenton type reaction of hydrogen peroxide with Co(II). The antioxidants from a sample react with the reactive oxygen species and decrease the chemiluminescence signal. It was drawn a calibration graph by plotting the ratio of chemiluminescence intensity in the absence and in the presence of an antioxidant and the concentration of a standard antioxidant (gallic acid). The calibration graph is linear in the domain 10(-6) - 10(-4) M galic acid. The method was applied for the analysis of three types of fruit juices. It has been done a comparison between the results for antioxidant capacity determination obtained with the developed method and the literature data for similar types of samples. The acuracy of the method was verified by using standard addition method.

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Arum dioscoridis and A. palaestinum (Araceae) are indigenous plant species in Jordan. HPLC-MS analysis of A. dioscoridis revealed the presence of apigenin, luteolin, quercetin, quercetin-3-O--glucoside, vitexin, isoorientin, esculin, and caffeic and ferulic acids. Both Arum spp., influenced gastrointestinal carbohydrate and lipid digestion and absorption. Orlistat inhibited dose dependently and highly substantially pancreatic lipase (PL) in vitro. Similar to orlistat, Arum species aqueous extracts (AEs), apigenin, caffeic acid and esculin exhibited a concentration related PL inhibition. Comparable to acarbose, dual inhibition of -amylase/-glucosidase was observed for both Arum species. Like guar gum, A. dioscoridis AE minimised substantially area under 24h glucose curve. Acute starch-induced postprandial hyperglycaemia in overnight fasting rats was highly significantly (p<0.001) decreased by A. dioscoridis AE. A. palaestinum could not perform effectively in either starch- or glucose-fed fasting rats. No antiproliferative effects against colorectal cancer cell lines HT29, HCT116 and SW620 were detected for tested Arum spp. [GRAPHICS] .

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A nanocomposite formed from molybdenum disulphide (MoS2) and graphene quantum dots (GQDs) was proposed as a novel and suitable support for enzyme immobilisation displaying interesting electrochemical properties. The conductivity of the carbon based screen-printed electrodes was highly improved after modification with MoS2 nanoflakes and GQDs, the nanocomposite also providing compatible matrix for laccase immobilisation. The influence of different modification steps on the final electroanalytical performances of the modified electrode were evaluated by UV-vis absorption and fluorescence spectroscopy, scanning electron microscopy, transmission electron microscopy, X ray diffraction, electrochemical impedance spectroscopy and cyclic voltammetry. The developed laccase biosensor has responded efficiently to caffeic acid over a concentration range of 038-100 mu M, had a detection limit of 0.32 mu M and a sensitivity of 17.92 nA mu M-1. The proposed analytical tool was successfully applied for the determination of total polyphenolic content from red wine samples. (C) 2015 Elsevier B.V. All rights reserved.

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Endocrine disrupting chemicals (EDCs) are harmful, xenobiotic compounds requiring a multi-tiered analytical approach for a reliable management. Although worth efforts worldwide, comprehensive EDCs monitoring and risk-assessment still require improvements. This article covers possible risks for public health due to EDCs exposure, and revises the maturity reached in different analytical detection fields, with a special focus on biosensor technology. Among validated laboratory-techniques, hyphenated mass spectrometry-based chromatography provides high selectivity and multi-analyte detection, while in vitro bioassays enable reliable toxicological testing. However, none of these methods is suitable for fast in field, continuous or semi-continuous operations. Due to advances in material science and synthetic biology, now biosensor technology holds the promise to close this gap and, although not included yet in routinely screening programs, fulfill the necessary requirements to sustain a coherent and global strategy to assess the state of environmental pollution. (C) 2016 Elsevier B.V. All rights reserved.

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The feasibility of using laccase from Trametes versicolor for degradation of aromatic hydrocarbons has been investigated. In the experiments, benzo[a]pyrene (BaP) was used. Laccase was immobilized onto mesoporous micelle-templated silica such as Santa Barbara Amorphous (SBA-15) and hexagonal mesoporous silica (HMS) as well as corresponding amino-functionalized supports. The best results were obtained for SBA-15 mesoporous silica however the HMS support could be as well considered for this type of application. The reusability of laccase immobilized into both silica supports was tested for five reaction cycles and the conversion reached about 70% of the initial value.

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Three mesoporous silica (MCM-41, MCM-48 and SBA-15), with different surface properties, pore size and porous structure, were synthesized and used as supports for laccase immobilization. The supports were functionalized with 3-aminopropyl-triethoxysilane (APTES) and 3-glycidyloxypropyltrimethoxy-silane (GPTMS). Laccase immobilization was carried out through physical adsorption and covalent binding on functionalized mesoporous silica with different textural properties. The obtained materials were characterized by X-ray diffraction at small angle, SEM and TEM microscopies, thermal analysis, N-2 adsorption-desorption, UV-Vis and FTIR spectroscopies. Immobilization yield and relative activity of laccase varied with pore size, functionalization and support pretreatment. The best values for these parameters were obtained for SBA-15 support functionalized with GPTMS after its pretreatment with glutaraldehyde. The influence of pretreatment time was also evidenced. The obtained biocatalysts were tested in oxidation of anisole and phenol with H2O2. The obtained results sustain the effect of support and method of immobilization on catalytic performances and biocatalysts stability.

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A Surface Plasmon Resonance (SPR) sensor for the quantitation of lysozyme dimer in monomer-dimer mixtures, reaching a detection limit of 1.4 nM dimer, has been developed. The sensor is based on an aptamer which, although developed for the monomeric form, binds also the dimeric form but with a strikingly different kinetics. The aptasensor was calibrated using a dimer obtained by cross-linking. Sensorgrams acquired with the aptasensor in monomer-dimer mixtures were analysed using Principal Components Analysis and Multiple Regression to establish correlations with the dimer content in the mixtures. The method allows the detection of 0.1-1% dimer in monomer solutions without any separation. As an application, the aptasensor was used to qualitatively observe the initial stages of aggregation of lysozyme solutions at 60 degrees C and pH 2, through the variations in lysozyme dimer amounts. Several other methods were used to characterize the lysozyme dimer obtained by cross-linking and confirm the SPR results. This work highlights the versatility of the aptasensor, which can be used, by simply tuning the experimental conditions, for the sensitive detection of either the monomer or the dimer and for the observation of the aggregation process of lysozyme. (C) 2016 Elsevier B.V. All rights reserved.

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The direct synthesis from elements of tungsten semicarbide, W2C, taking place in a narrow concentration range and at high temperatures, is unsuited for some applications requiring small particle sizes. We report an efficient synthesis method for obtaining pure phase W2C at low temperatures (< 1050 degrees C), through the carbothermal reduction of tungsten oxide species in the presence of metallic palladium nanoparticles obtained in situ. A 1:5 (at.) Pd:W ratio or higher yields pure phase W2C, while increasing the Pd content decreases the carburization temperature. The resulting composite materials contain Pd(0) and W2C particles well-dispersed on carbon, with sizes between 50 and 500 nm. The samples have been tested using cyclic voltammetry and chronoamperometry as potential anode materials for the electrooxidation of formic acid and show improved stability in comparison with commercial Pd and comparable current densities, up to 2 times higher than the commercial catalyst. (C) 2016 Elsevier B.V. All rights reserved.

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beta-Carbolines are inhibitors of monoamine oxidases (MAO-A and MAO-B) and can be found in foods, hallucinogenic plant or various drugs. We have developed a fast analysis method for beta-carbolines based on the inhibition of MAO. The enzymes were immobilized on screen-printed electrodes modified with a stabilized film of Prussian blue that contain also copper. We have used benzylamine as substrate for the enzymatic reaction and the hydrogen peroxide was measured amperometrically at -50 mV. The detection limits obtained were 5.0 mu M for harmane and 2.5 mu M for both harmaline and norharmane. The MAO-A is inhibited by all three tested beta-carbolines (harmane, norharmane, and harmaline) while MAO-B is inhibited only by norharmane. The presence of norharmane in mixtures of beta-carbolines can be identified based on the difference between the cumulative inhibition of MAO-A by all beta-carbolines and MAO-B inhibition. The developed biosensors were used for food analysis. (C) 2015 Elsevier B.V. All rights reserved.

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The optimization of an aptasensor with SPR detection allowed the determination of an allergen protein, lysozyme, with high accuracy, good sensitivity and a detection limit of 2.4 nM for spiked red and white wines. The interaction of lysozyme with specific phenolic compounds from wine was evidenced by circular dichroism and SPR. Quantitative recovery factors higher than 88% for wine lysozyme were achieved based on a sample pre-treatment procedure with high concentration of sodium chloride and Tween-20. This aptasensor is useful to monitor the lysozyme levels during winemaking. Also reported is a new chromatographic method based on size exclusion that provided a good separation of lysozyme from wine components, with a detection limit of 35 nM or 0.5 mu g/mL. (C) 2014 Elsevier B.V. All rights reserved.

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In this work a novel sensor array platform based on a dual carbon screen-printed electrode was developed for the simultaneous determination of chlorogenic acid and caffeine. One of the carbon working electrodes was modified with platinum nanoparticles, reduced graphene oxide and laccase (C-SPE/Pt-NPs/RGO/lacc-biosensor) for chlorogenic acid determination and the second carbon working electrodes was modified with reduced graphene oxide and Nafion (C-SPE/RGO/Nafion-sensor) for caffeine determination. Cyclic voltammetry was used to characterise and optimise the dual sensor array while chronoamperometry was used to investigate the bioelectrocatalytic response. The C-SPE/Pt-NPs/RGO/lacc for biosensing chlorogenic acid exhibited a sensitivity of 0.02 mu A mu M (1) and a detection limit of 2.67 mu M whereas the C-SPE/RGO/Nafion used for sensing caffeine has showed a sensitivity of 1.38 mu A mu M-1 and a detection limit of 0.22 mu M. The developed sensor array was used to determine these two major coffee bean compounds from real coffee samples. Due to its simplicity, feasibility and accessibility, the developed dual sensor array could represent the basis of a valuable analytical tool able to screen both chlorogenic acid and caffeine content from coffee samples offering important information about the phytochemical composition of the samples.

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Context: Eryngium planum, Geum urbanum and Cnicus benedictus plants are an endemic botanical from the Romanian used in folk medicine. Objective: The extracts from three Romanian medicinal plants were investigated for their possible neuroprotective potential. Materials and Methods: Within this study, in vitro neuroprotective activity of the extracts of E. planum, G. urbanum, and C. benedictus plants were investigated via inhibition of acetylcholinesterase (AChE) and tyrosinase (TYR). Total content of phenolics, flavonoids, and proanthocyanidins, high-performance liquid chromatography profile of the main phenolic compounds and antioxidant activity were also determined. Results: Among the tested extracts, the best inhibition of AChE (88.76 +/- 5.2%) and TYR (88.5 +/- 5.2%) was caused by C. benedictus ethanol (EtOH) extract. The G. urbanum extracts exerted remarkable scavenging effect against 2,2-diphenyl-1-picrylhydrazyl (IC 50, 7.8 +/- 0.5 mu g/mL aqueous extract, and IC50, 1.3 +/- 0.1 mu g/mL EtOH extract, respectively) and reducing power, whereas the EtOH extract of C. benedictus showed high scavenging activity (IC 50, 0.609 +/- 0.04 mg/mL), also. Conclusion: According to our knowledge, this is the first study that demonstrates in vitro neuroprotective effects of E. planum, G. urbanum and C. benedictus.

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The main objective of this study is to concentrate the antioxidant bioactive compounds from the hydroalcoholic extract of Phyllitis scolopendrium through the poly(1,4-phenylene ether ether sulfone) (PPEES) ultrafiltration membrane. The PPEES membrane was prepared using the phase inversion method. The total content of phenolics and flavonoids, HPLC profile of the main phenolic compounds, and antioxidant and anti-tyrosinase activities were also determined in the microfiltrate, permeate and concentrate. When the PPEES membrane is used the concentration of polyphenols and flavonoids is higher, reaching the retention index of 0.785 and of 0.683, respectively, than that measured in the case of processing the feed through the PSF membrane. PPEES membranes showed a higher concentration towards anti-tyrosinase compounds (71.9 +/- 4.3%), compared with the PSF membranes (58.7 +/- 2.9%). The obtained results proved that the PPEES membrane we have prepared is suitable for the bioactive compound's concentration from the herbal extracts. This could result in their wide application in the food and pharmaceutical industries.

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Different Roumanian propolis ethanolic extracts were investigated regarding their content in total polyphenols, flavones, flavonols, flavanones and dihydroflavonols. The antioxidant activities were assessed using systems such as 1, 1-diphenyl-2-picrylhydrazyl, 2, 2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid), ferric reducing ability power and linoleic acid emulsion; the results were correlated with the concentrations in active compounds. A high performance liquid chromatography with diode array detection validated method was used for quantitation of 17 polyphenolic compounds in Roumanian propolis samples. The results confirmed that Roumanian propolis is an important sources of polyphenols and possesses a strong antioxidant activity.

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Medicinal plants represent an important source of active biological compounds that could be used for new drugs development. The present work aims the assessment of two Romanian medicinal plants that were not well studied Alchemilla vulgaris and Filipendula ulmaria with respect to their neuroprotective potentiality. The aqueous extracts (10% mass) and ethanolic extracts (10% mass and 70% (v/v) ethanol) of A. vulgaris and F. ulmaria were screened to evaluate their acetylcholinesterase and tyrosinase inhibitory effects as well as their antioxidant activity. The antioxidant activity was determined using two methods, namely 2,2-diphenyl-1-picrylhydrazyl (DPPH) and reducing power assay. The total polyphenolic content determined in the tested compounds was between 88.00 and 112.33 mu g/mL, flavones between 360.00 and 862.00 mu g/mL and proanthocyanidins between 77.66 and 130.00 mu g/mL. The acetylcholinesterase inhibitory activity was determined to be between 77.03 and 98.39% (at the highest used dose -3 mg/mL), the tyrosinase inhibitory activity was found to be between 60.00 and 90.65% (at 3 mg/mL) and the DPPH radical inhibition between 73.90 and 93.49%. These findings support the use of these medicinal plants in the treatment of neurodegenerative disorders such as Parkinson, Alzheimer. (C) 2015 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

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The present work describes the development of an electrochemical method based on the use of 2,2'-diphenyl-1-picrylhidrazyl free radical (DPPH.) for the determination of the antiradical properties of several olive oils. Differential pulse voltammetry was used as measuring technique while the electrochemical process was recorded at a platinum screen-printed working electrode. The decrease in 2,2'-diphenyl-1-picrylhidrazyl peak current intensity was measured at a specific potential value of +160 mV vs. screen-printed pseudo-reference electrode, in the presence of alpha-, delta- and gamma-tocopherol and olive oil samples, respectively. The obtained results using differential pulse voltammetry, as detection technique for real samples analysis, showed a satisfactory agreement with those obtained by high-performance liquid chromatography coupled with fluorescence detection. The reported electrochemical method is rapid and easy to use, feasible and accessible to be used as an alternative to 2,2'-diphenyl-1-picrylhidrazyl spectrophotometric based method. (C) 2014 Elsevier Ltd. All rights reserved.

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Quantitative evaluation of organic acids in plants and foodstuff is important for flavour and nutritional studies and also could be used as indicator of bacterial activity. Organic acids occurring in foods are additives or end-products of carbohydrate metabolism of lactic acid bacteria (LAB). A good selection of LAB (and a criterion should be the content in organic acids) allows the control of mould growth and improves the shelf life of many fermented products and, therefore, reduces health risks due to exposure to mycotoxins. A simple, rapid (15 min) and reliable capillary electrophoresis method was partially validated for the simultaneous quantification of nine aliphatic (formic, oxalic, succinic, malic, tartaric, acetic, citric, lactic, butyric) and three aromatic (benzoic, phenyllactic and hydroxyphenyllactic) organic acids in the fermentation products of lactic acid bacteria. The method was validated in terms of linearity of response, limit of detection (LoD), limit of quantification (LoQ), precisions (i.e. intra-day, inter-day reproducibility) and recovery. The method is simple, rapid, reliable and cost-effective.

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In this paper, a liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry in negative mode method was developed for the identification and quantitative determination of 13 individual phenolics (chlorogenic acid, caffeic acid, coumaric acid, ferulic acid, (1)-catechin, (-)-epicatechin, rutin, quercitrin, isoquercitrin, fisetin, isorhamnetin, hesperidin and chrysin) from ethanolic extracts [30, 50 and 70% (w/v)] of Calendula officinalis, Hypericum perforatum, Galium verum and Origanum vulgare and some commercial extracts of these medicinal herbs. Correlation coefficients (r(2)) from calibration curves for all the compounds were between 0.9971 and 0.9996. Limit of detection was in the range of 0.070-0.280 mg/mL and limit of quantification was from 0.233 to 0.932 mg/mL. The method was partially validated and the results obtained are: the intra-and interday relative standard deviation values were within 0.086 and 2.821% and recovery values vary from 95.84% (coumaric acid) to 103.20% (rutin).

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Some plants collected (Mentha aquatica, Bidens tripartita and Ambrosia artemisiifolia) from an unusual habitat developed in recent years in Bucharest (the so-called Bucharest Delta) and the contents of polyphenolic compounds, short-chain organic acids and heavy metals, and radical scavenger activity, were determined. 12 polyphenolic compounds and 7 short-chain organic acids were quantified using high-performance liquid chromatography and capillary electrophoresis; Mentha aq. extracts presented the highest levels of rosmarinic acid (1.58 mg g(-1)) and ferulic acid (2.84 mg g(-1)) and Bidens extracts presented the highest concentrations of chlorogenic acid (0.44 mg g(-1)); the same extracts contain the most important levels of luteolin (0.52 mg g(-1)) or other flavonoids. All the heavy metals detected in the plants studied were found in very low levels (the highest was Pb(II) in Mentha aquatica, (12.84 +/- 0.48) mu g kg(-1)). The study sought to identify the active compounds and some contaminants in plants collected from the Bucharest Delta with the intention of eventual exploitation of the habitat and to enhance the knowledge of such human-modified ecosystems. (C) 2015 Institute of Chemistry, Slovak Academy of Sciences

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In this work, a simple, reliable and fast capillary electrophoresis method was developed and partially validated for simultaneous detection of 20 polyphenolic compounds (presumed to be found in propolis and plant extracts) in less than 27 min. The best results were obtained using 45 mM tetraborate buffer with 0.9 mM sodium dodecyl sulfate (pH = 9.35) as a background electrolyte. The polyphenolic compound order of elution was the following: resveratrol, pinostrobin, acacetin, chrysin, rutin, naringenin, isoquercitrin, umbelliferone, cinnamic acid, chlorogenic acid, galangin, sinapic acid, syringic acid, ferulic acid, kaempferol, luteolin, coumaric acid, quercetin, rosmarinic acid and caffeic acid. Linearity ranges used for compound quantification were satisfactory, presenting correlation coefficients between 0.997 and 0.999 for all 20 compounds. The method showed good performance characteristics: detection and quantification limits of 0.02 to 1.75 and 0.07 to 5.77 mu g mL(-1), respectively. The relative standard deviation values for repeatability did not exceed 4.86 % for intra-day assays and 5.07 % for inter-day assays. The recovery assays presented results between 87.4 and 114. 2 % for Origanum sample and between 85.0 and 111.0 % for propolis sample. The results obtained from the analysis of samples are in good correlation with literature data and bring new information about less studied samples such us aqueous Romanian propolis extracts and ethanolic Mentha aquatica extract.

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Dipyridine derivatives are used on large scale and pose significant environmental problems. We have synthesized dipyridine derivatives with: 5-chlorovaleric acid, alpha-dichlorhidrin, iodoacetamide and 11-bromoundecanoic acid. The synthesized substituted compounds were investigated by LC-MS. The adsorptive removal of dipyridine derivatives from aqueous solution has been studied using medicinal activated carbon. The adsorption rate has been investigated under the controlled process parameters including adsorption time, carbon and organic compound concentration. The results from this study demonstrated that the activated carbon can be used as a low-cost adsorbent for the removal of environmental cationic dipyridine derivatives from the water environment.

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The main goal of our study was to evaluate the effect of the individual administration of five lyophilized lactic acid bacteria strains (Lactobacillus fermentum 428ST, Lactobacillus rhamnosus E4.2, Lactobacillus plantarum FCA3, Lactobacillus sp. 34.1, Weissella paramesenteroides FT1a) against the in vitro simulated microbiota of the human colon using the GIS1 system. The influence on the metabolic activity was also assessed by quantitative determination of proteins and polysaccharides at each segment of human colon. The obtained results indicated that the lactic acid bacteria L. rhamnosus E4.2 and W. paramesenteroides FTa1 had better efficiency in synthesising exopolysaccharides and also a better probiotic potential and therefore could be recommended for use in probiotics products or food industry.

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Biosensors are powerful tunable systems able to switch between an ON/OFF status in response to an external stimulus. This extraordinary property could be engineered by adopting synthetic biology or biomimetic chemistry to obtain tailor-made biosensors having the desired requirements of robustness, sensitivity and detection range. Recent advances in both disciplines, in fact, allow to re-design the configuration of the sensing elements - either by modifying toggle switches and gene networks, or by producing synthetic entities mimicking key properties of natural molecules. The present review considered the role of synthetic biology in sustaining biosensor technology, reporting examples from the literature and reflecting on the features that make it a useful tool for designing and constructing engineered biological systems for sensing application. Besides, a section dedicated to bioinspired synthetic molecules as powerful tools to enhance biosensor potential is reported, and treated as an extension of the concept of biomimetic chemistry, where organic synthesis is used to generate artificial molecules that mimic natural molecules. Thus, the design of synthetic molecules, such as aptamers, biomimetics, molecular imprinting polymers, peptide nucleic acids, and ribozymes were encompassed as products of biomimetic chemistry. (C) 2015 Elsevier B.V. All rights reserved.

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An optimized electrochemical sensor was developed to assess the antioxidant capacity of carotenoids, accumulating during the life cycle of Haematococcus pluvialis cell cultures. The sensor was improved with a composite renewable surface made of immobilised phosphatidylcholine (PC) on magnetic nanobeads of iron oxide (Fe3O4) and PC/Fe3O4, and it was used to monitor the antioxidant properties of the ketocarotenoid astaxanthin against in situ generated phosphatidylcholine lipoperoxides. The surface configuration was able to mimic the natural position and orientation of astaxanthin in the cellular membrane, conferring to the whole experimental set-up good sensitivity for reactive oxygen species (limit of detection for peroxyl radicals 9.1 x 10(-10) mol L-1) with a linear response ranging between 10(-8) and 1.6 x 10(-6) mol L-1. The sensor has been proved suitable for both batch and flow measurements. The accuracy of the flow measurements was unaffected by the magnetic field intensity. Electrochemical measurements confirmed that natural astaxanthin is a more effective antioxidant than synthetic astaxanthin, vitamin E and lutein and the protective effect of astaxanthin correlates with its concentration inside the cell. The newly developed sensor is hence useable for in-line monitoring of whole-cell based industrial bioprocesses for the production of astaxanthin.

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The goal of this paper aimed the development of an inexpensive, reliable and easy-to-use biodevice for detection and monitoring of phenol and phenolic endocrine disruptors in water samples. X-Ray (XRD) diffraction technique was employed for physical characterization of the modified electrode surface, results revealing nanostructured layers assemblies of polycrystalline gold with (200) growth preferred orientation and gold crystallite size of 33.19 nm. Investigation of the modified surface charge transfer properties was performed using cyclic voltammetry technique highlighting a significant enhancement of the electron transfer rate. Dual signal amplification offered by synergistic effect of gold nanoparticle and reduced graphene oxide layers and tyrosinase led to competitive detection limits (7.2 x 10(-8) mol L-1 for phenol and 4.8 x 10(-7) mol L-1 for octylphenol) and sensitivities (416 nA/mu mol for phenol and 155 nA/mu mol for octylphenol). The obtained values of the K-m(app) and I-max/K-m(app) ratio confirmed a strongly dependence of the immobilized tyrosinase catalytic efficiency on the steric and electronic properties of the bulky side chain in the para position of the phenolic compound. The biodevice showed a percent recovery between 87 +/- 8% and 94 +/- 11% demonstrating a suitable degree of accuracy and confirming the application potential to the detection and monitoring of phenol and several endocrine disruptors in water samples. (C) 2015 Elsevier B.V. All rights reserved.

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Hypercholesterolemia is a predominant risk factor for atherosclerosis and associated with coronary and cerebrovascular diseases. The global incidence of hypercholesterolemia is rapidly increasing. Adiantum capillus veneris L. (Adiantaceae) has been reported as herbal medicine for diverse ailments in Jordan. However, its alleged benefits and action mechanisms remain elusive. Thus the present study aimed to identify the phenolic constituents of A. capillus veneris by LC-MS and to evaluate the chronic effect of its water extract on 10-weeks high cholesterol diet (HCD)-fed rats serum lipid profile and atherogenic index. Antioxidant potential is also assessed. Rats were divided into four groups of 6 rats each. Group 1 was kept on stand diet; the remaining three groups were high-cholesterol fed for ten weeks. On week 7 onwards; Group 3 was atorvastatin 10 mg/Kg b.wt- treated, while group 4 was supplemented daily with A. capillus veneris 500 mg/Kg b.wt. HPLC-MS analyses revealed the presence of ellagic acid (5.48 mg/g), rutin (4.77 mg/g), quercetin-3-O-glucoside (3.96 mg/g), ferulic acid (3.88 mg/g), gallic acid (3.44 mg/g), caffeic acid (1.55 mg/g), epicatechine (1.34 mg/g) and quercetine (0.43 mg/g). Crude extracts of the aerial parts exhibited potent antioxidant activity by ORAC, ABTS and DPPH assays (2184.95 +/- 109.3, 762.50 +/- 38.1, and 337.07 +/- 16.9 Trolox equivalent nmol/mg, respectively). Exceeding atorvastatin 10 mg/Kg b.wt effectiveness (p<0.05, n=6 rats/group), 10-week administration of A. capillus veneris extract in HCD-fed rats decreased highly significantly the total cholesterol (TC), LDL and VLDL serum levels. VLDL serum levels in both intervention groups were substantially (p<0.001) and comparably decreased. Neither treatment could affect HDL serum levels. Besides, atherogenic index parameter of TC/HDL was normalized in A. capillus veneris-treated rats. A. capillus veneris can be considered as potential candidate for management of hypercholesterolemia and its atherosclerotic complications.

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Forty-four propolis samples collected from various regions of Romania were assessed by a validated method of high performance liquid chromatography with diode array detection for quantifying twelve important flavonoids and polyphenolic acids. The chromatographic data coupled with statistical analysis revealed two distinct groups of samples: the group corresponding to a plain climate and the group corresponding to plateau and upper hills climate. In addition to other statistical studies based on qualitative data, we can mention the compounds which are responsible for discrimination between propolis groups.

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The Romanian propolis was extracted in five different media, respectively, in water (pH 6.8), glycine buffer (pH 2.5), acetate buffer (pH 5), phosphate buffer (pH 7.4) and carbonate buffer (pH 9.2). The extracts presented different amounts of flavonoids and phenolic acids, increasing pH leading to higher concentrations of active compounds. Five variants of gold nanoparticles suspensions based on different pH Romanian propolis aqueous extracts were successfully synthesized. The obtained nanoparticles presented dimensions between 20 and 60 nm in dispersion form and around 18 nm in dried form, and different morphologies (spherical, hexagonal, triangular). Fourier transform infrared spectroscopy proved the attachment of organic compounds from propolis extracts to the colloidal gold suspensions and X-ray diffraction certified that the suspensions contain metallic gold. The obtained propolis gold nanoparticles do not exhibit any antibacterial or antifungal activity, but presented different catalytic activities and toxicity on tumour cells.

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We report the experimental results that refer to a Fourier transform Raman (FT-Raman) survey of thermally altered Baltic and Romanian amber and the related statistical interpretation of data using principal component analysis (PCA). Although FT-Raman spectra show several small changes in the characteristic features of the investigated amber samples which may be used for discrimination, their visual recognition is relatively difficult, especially when interpreting data from archeological samples, and thus multivariate data analysis may be the solution to more accurately assign the geological origin based on overall characteristic spectral features. The two categories of amber have different behavior in terms of degradation during the experimental alteration, and Romanian amber is more susceptible to physico-chemical transformations by the aggressive environment when compared with Baltic amber. The obtained data were in accordance with the Fourier transform infrared (FT-IR) remarks published previously in a dedicated journal. The Raman technique is an alternative method that requires little to no sample preparation, water does not cause interference, and the spectra can be collected from a small volume (1-50 mu m in diameter).

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Some plants collected (Mentha aquatica, Bidens tripartita and Ambrosia artemisiifolia) from an unusual habitat developed in recent years in Bucharest (the so-called "Bucharest Delta") and the contents of polyphenolic compounds, short-chain organic acids and heavy metals, and radical scavenger activity, were determined. 12 polyphenolic compounds and 7 short-chain organic acids were quantified using high-performance liquid chromatography and capillary electrophoresis; Mentha aq. extracts presented the highest levels of rosmarinic acid (1.58 mg g-1) and ferulic acid (2.84 mg g-1) and Bidens extracts presented the highest concentrations of chlorogenic acid (0.44 mg g-1); the same extracts contain the most important levels of luteolin (0.52 mg g-1) or other flavonoids. All the heavy metals detected in the plants studied were found in very low levels (the highest was Pb(II) in Mentha aquatica, (12.84 ± 0.48) μg kg-1). The study sought to identify the active compounds and some contaminants in plants collected from the "Bucharest Delta" with the intention of eventual exploitation of the habitat and to enhance the knowledge of such human-modified ecosystems. © 2015 Institute of Chemistry, Slovak Academy of Sciences.

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β-Carbolines are inhibitors of monoamine oxidases (MAO-A and MAO-B) and can be found in foods, hallucinogenic plant or various drugs. We have developed a fast analysis method for β-carbolines based on the inhibition of MAO. The enzymes were immobilized on screen-printed electrodes modified with a stabilized film of Prussian blue that contain also copper. We have used benzylamine as substrate for the enzymatic reaction and the hydrogen peroxide was measured amperometrically at -50 mV. The detection limits obtained were 5.0 μM for harmane and 2.5 μM for both harmaline and norharmane. The MAO-A is inhibited by all three tested β-carbolines (harmane, norharmane, and harmaline) while MAO-B is inhibited only by norharmane. The presence of norharmane in mixtures of β-carbolines can be identified based on the difference between the cumulative inhibition of MAO-A by all β-carbolines and MAO-B inhibition. The developed biosensors were used for food analysis. © 2015 Elsevier B.V. All rights reserved.

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capillary electrophoresis has proved to be a good alternative technique to high performance liquid chromatography for the investigation of various compounds due to its good resolution, versatility, simplicity, short analysis time and low consumption of chemicals and samples. This chapter presents a synthesis of our work regarding applications of capillary electrophoretic methods (capillary zone electrophoresis with diode array detection): the separation of small-chain organic acids from plants extracts, wines, lactic bacteria fermentation products, and the separation of polyphenolic compounds from propolis extracts, plant extracts and wines. Quantitative evaluation of organic acids in plants and foodstuff is important for flavour and nutritional studies, and also could be used as marker of bacterial activity. Organic acids occurring in foods are additives or end-products of carbohydrate metabolism of lactic acid bacteria. A good selection of lactic acid bacteria, in terms of content in organic acids, allows the control of mould growth and improves the shelf life of many fermented products and, therefore, reduces health risks due to exposure to mycotoxins. On the other side, the largely studied group of phytochemicals is polyphenols, an assembly of secondary metabolites with various chemical structures and functions and biological activities, which are produced during the physiological plant growth process as a response to different forms of environmental conditions. The methods for separation and quantification of organic acids and polyphenolic compounds were validated in terms of linearity of response, limit of detection, limit of quantification, precisions (i.e., intra-day, inter-day reproducibility) and recovery. The methods are simply, rapid, reliable and cost effective. © 2015 by Nova Science Publishers, Inc. All rights reserved.

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Dipyridine derivatives are used on large scale and pose significant environmental problems. We have synthesized dipyridine derivatives with: 5-chlorovaleric acid, alpha-dichlorhidrin, iodoacetamide and 11-bromoundecanoic acid. The synthesized substituted compounds were investigated by LC-MS. The adsorptive removal of dipyridine derivatives from aqueous solution has been studied using medicinal activated carbon. The adsorption rate has been investigated under the controlled process parameters including adsorption time, carbon and organic compound concentration. The results from this study demonstrated that the activated carbon can be used as a low-cost adsorbent for the removal of environmental cationic dipyridine derivatives from the water environment.

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A rapid, simple and stable biosensor for aspartame detection was developed. Alcohol oxidase (AOX), carboxyl esterase (CaE) and bovine serum albumin (BSA) were immobilised with glutaraldehyde (GA) onto screen-printed electrodes modified with cobalt-phthalocyanine (CoPC). The biosensor response was fast. The sample throughput using a flow injection analysis (FIA) system was 40 h(-1) with an RSD of 2.7%. The detection limits for both batch and FIA measurements were 0.1 mu M for methanol and 0.2 mu M for aspartame, respectively. The enzymatic biosensor was successfully applied for aspartame determination in different sample matrices/commercial products (liquid and solid samples) without any pre-treatment step prior to measurement.

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The anticholinesterase activity of four biochemical pesticides: spinosad, pyrethrum, neem bark extract and veratrine was tested against one acetylcholinesterase extracted from Electrophorus electricus and two from Drosophila melanogaster. Pyrethrum, neem bark extract, and veratrine induced a dose-related inhibition of a variable type. Electric eel cholinesterase was inhibited uncompetitively by neem bark extract, the inhibition of the wilde-type fruit fly enzyme by pyrethrum was competitive, and the other enzyme-biochemical pesticide inhibitions were non-competitive. The sensitivity of each enzyme toward biochemical pesticides was variable. (C) Pesticide Science Society of Japan

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The aim of this study was to determine the best conditions to obtain the highest total polyphenol content from Salvia officinalis hydroalcoholic and aqueous extracts and to study the main bioactive compounds and the antioxidant activity of the concentrate obtained during ultrafiltration. 8%, 10% and 15 % (mass concentration) hydroalcoholic extracts of Salvia officinalis in 70% ethanol and an aqueous extract (8%) were prepared. The obtained extracts were further purified and concentrated through membrane procedures (ultrafiltration). The aqueous extracts were successively concentrated through ultrafiltration membranes of regenerated cellulose with 10000 Da, than 5000 Da and 3000 Da, the highest concentration being obtained using the 3000 Da Millipore membranes. For hydroalcoholic extracts 3 types of membranes were used: Millipore ultrafiltration membranes with cut-off of 10.000 Da and 5.000 Da and polysulfone composite membrane (PSF). The contents of total polyphenols, proteins, reducing sugars and flavones were determined. The values ranged between: 321.23 - 404.21 mu g/mL - polyphenols, 1.04 - 1.72 mg/mL - proteins, 26.01 - 99.48 mg/mL - flavones and 35.05 - 138.16 mu g/mL - sugars. The concentrated extracts showed promising levels of DPPH radical scavenging activity (42.12%-70.82%), the highest values being obtained for the extracts concentrated by Millipore membranes 5000 Da.

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We have modified a glassy carbon electrode (GCE) with nanoparticles composed of a 4,4'-bipyridinesilver coordination polymer (CP) and showed that this CP can be applied to the sensitive differential pulse voltammetric analysis of the ions Hg(II), Cu(II) and Pb(II). The coordination polymer was prepared by mixing a solution of silver nitrate and 4,4'-bipyridine at room temperature. The surface of the GCE was modified with an organic layer of synthesized 1-[(4-nitrophenyl)methyl]-4,4'-bipyridinium and silver ions, which caused the binding of the added Ag-bipy CP. Anodic (oxidative) peaks of the electrode were at +300 mV for Hg(II), -70 mV for Cu(II), and at -540 mV for Pb(II) [versus Ag/AgCl]. Under optimal conditions, calibration graphs were linear in concentration ranges from 0.2 to 10 mu g L-1 for Hg(II), from 1.3 to 6.4 mu g L-1 for Cu(II), and from 4.1 to 20.7 mu g L-1 for Pb(II). The respective detection limits were 0.09 mu g L-1 Hg(II), 0.71 mu g L-1 Cu(II) and 2.3 mu g L-1 Pb(II). Relative standard deviation was 3.2% at a level of 4 mu g L of Hg(II) for n = 10. The modified electrode was applied to the analysis of Hg(II) in spiked fish samples, and of Cu(II), Pb(II), and Hg(II) in spiked plant samples, and recoveries ranged from 90 to 108%. This is the first paper that presents the use of 4,4'-bipyridine-silver coordination polymer for heavy metal electrochemical detection.

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This study was meant to determine the inhibitory activity of tannins and flavonoid compounds from Geranium robertianum, Helleborus purpurascens and Hyssopus officinale plant polyphenol rich extracts against urease and alpha-chymotrypsin. The G. robertianum, H. purpurascens and H. officinale extracts were purified and concentrated by microfiltration and ultrafiltration. Phenolic compounds including flavonoids and tannins have been linked to many pharmacological activities. Thus, the polyphenolic content of the extracts was assessed by UV-Vis spectroscopy and HPLC. The concentrated extracts enriched in polyphenolic compounds (flavonoids, tannins and phenolic acids) showed a significant inhibition against urease from jack bean (over 90%), whereas in case of the alpha-chymotrypsin, they proved to have an inhibition below 54%. The results of this support the use of G. robertianum, H. purpurascens and H. officinale polyphenolic extracts as potential sources of urease inhibitors. Among the three plant extracts tested, H. officinale polyphenolic extracts exhibited a high inhibitory activity (92.67%) against urease and low inhibition (19.6%) against alpha-chymotrypsin and could be considered as possible remedy in ulcer treatment.

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Protein aggregates adsorb to material surfaces in a different manner than protein monomers and pose additional challenges for biosensor development with regard to non-specific adsorption (NSA). In this context, we describe herein the performance of a new antifouling thiol in a sensor coating resistant to NSA from lysozyme monomers and aggregates. Coatings were prepared as mixed self-assembling monolayers (SAMs) using a long polyethylene glycol carboxyl-terminated thiol (PEG-COOH) for the first time in conjunction with a shorter monoethylene glycol hydroxyl-terminated diluent thiol (MEG-OH). SAMs and their antifouling properties were characterized by a variety of surface analysis techniques. A key result was that the cleaning procedure drastically affects the antifouling properties of resulting MEG-OH based SAMs. Mixed PEG-COOH/MEG-OH SAMs formed on borohydride cleaned interfaces are able to reduce lysozyme NSA by >90% compared to bare gold; a remarkable performance also displayed for oligomers regardless of their stage of aggregation. Gratifyingly, subsequent SAM functionalisation with an anchoring layer of neutravidin for the preparation of a lysozyme sensor did not significantly alter the antifouling properties of the resulting assembly. The limit of detection for monomeric lysozyme by surface plasmon resonance was 0.3 mg mL(-1) with a dynamic range of 3-50 mg mL(-1) (R-2 = 0.9993). The sensitivity of the technique for the aggregated lysozyme was almost two times higher than that for the protein monomer.

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Experimentally developed ceramic pots, with two different sizes of grain, were half-filled with wine and subjected to thermal alteration at constant elevated temperature ((60 +/- 2)A degrees C) in darkness for 12 weeks. This work sought to characterise the samples thereby obtained from chemical and mineralogical perspectives using scanning electron microscopy and an energy-dispersive X-ray microanalysis system (SEM-EDX), Fourier transform infrared spectroscopy (FTIR) and capillary electrophoresis (CE) with UV detection as an alternative to chromatographic methods, due to its good resolution, automation, simplicity, high speed, low consumption of chemicals and short time required for sample preparation. The capillary electrophoresis method was used for the detection of five wine biomarkers: succinic acid, malic acid, tartaric acid, citric acid and lactic acid. In general, it was noted that the fine-grained ceramic assortment retained the organic material better than the coarser-grained ceramics. An interesting observation derived from this study was that not only could tartaric acid be considered as a biomarker for wine residues in archaeological pottery, but malic acid could also act similarly for white wine and lactic acid for red wine.

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In this work we present a rapid, selective, and highly sensitive detection of a-solanine and a-chaconine using cholinesterase-based sensors. The high sensitivity of the devices is brought by the use of a genetically modified acetylcholinesterase (AChE), combined with a one-step detection method based on the measurement of inhibition slope. The selectivity was obtained by using butyrylcholinesterase (BChE), an enzyme able to detect these two toxins with differential inhibition kinetics. The enzymes were immobilized via entrapment in PVA-AWP polymer directly on the working electrode surface. The analysis of the resulting inhibition slope was performed employing linear regression function included in Matlab. The high toxicity of a-chaconine compared to a-solanine due to a better affinity to the active site was proved. The inhibition of glycoalkaloids (GAs) mixture was performed over AChE enzyme wild-type AChE and BChE biosensors resulting in the detection of synergism effect. The developed method allows the detection of (GAs) at 50 ppb in potato matrix. (C) 2014 Elsevier Inc. All rights reserved.

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Indium doped tin oxide (ITO) electrodes were functionalized with gold nanoparticles (GNPs) and cysteamine monolayer to enhance the heterogeneous electron transfer process of laccase from Trametes versicolor. The assembly of GNP on ITO support was performed through generation of H+ species at the electrode surface by hydroquinone electrooxidation at 0.9 V vs Ag/AgCl. Uniform distribution of gold nanoparticle aggregates on electrode surfaces was confirmed by atomic force microscopy. The size of GNP aggregates was in the range of 200-500 nm. The enhanced charge transfer at the GNP functionalized ITO electrodes was observed by cyclic voltammetry (CV) and electrochemical impedance spectroscopy. Electrocatalytic behavior of laccase immobilized on ITO modified electrode toward oxygen reduction reaction was evaluated using CV in the presence of 2,2'-azino-bis 3-ethylbenzothiazoline-6-sulfuric acid (ABTS). The obtained sigmoidal-shaped voltammograms for ABTS reduction in oxygen saturated buffer solution are characteristic for a catalytic process. The intensity of catalytic current increased linearly with mediator concentration up to 6.2 x 10(-4) M. The registered voltammogram in the absence of ABTS mediator clearly showed a significant faradaic current which is the evidence of the interfacial oxygen reduction. (C) 2014 Elsevier B.V. All rights reserved.

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The aim of the present work was to widen the application of an in-house developed fast, flexible and sensitive high performance liquid chromatography (HPLC) method to the assessment of cefotaxime sodium from aqueous samples. The method was applied to establish the release profile of cefotaxime sodium immobilised in MCM-41 nanoparticles using pH-controlled release in an aqueous medium. The analytical method proved to be sensitive, repeatable (RSD < 1.5 %) and reproducible (RSD < 1 %) in the studied concentration range (0.01-10 mu g.mL(-1)). The limit of detection and limit of quantification were 0.036 and 0.12 mu g.mL(-1), respectively, suitable for the analysis of the release of a single active ingredient, and the analysis time was short (10 min).

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A method based on reversed-phase liquid chromatography (RP-LC) with diode array detection (DAD) has been developed and validated in order to quantitate several polyphenols from different extracts. Samples were separated on a Fortis C18 reversed-phase column (250 x 4.6 mm, 5 mu m) with a gradient of acetonitrile and aqueous phosphoric acid, pH=2.5. The complete separation of seventeen polyphenols was achieved within 60 min. All calibration curves expressed good linearity (r(2) > 0.997) within the test range. The recovery of this method was in the range 88.12-107.87% and for the intra-day and inter-day assays, the values of deviation coefficient were less than 5%. The assay was successfully applied to the quantitation of polyphenols from 9 samples of propolis ethanolic extracts purchased from Roumanian market. The results indicated that this developed RP-LC assay could be readily utilized as a quality control method of various natural extracts.

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1-[(4-nitrophenyl) methyl]-4,4'-bipyridinium (N-PMB) was synthesized by refluxing 4,4'-bipyridine and 4-nitrobenzylchloride. A stable film of 1-phenylmethyl-4,4'-bipyridine (PMB) was successfully electrografted on glassy carbon electrodes by the reduction of the diazonium moieties generated in situ. High antifouling ability was obtained for the PMB modified electrode which makes it a useful sensor device for environmental waters monitoring. The modified electrode was used as an amperometric sensor for mediated hydrogen peroxide detection at -0.5 V. The calibration curve was linear from 5 to 60 mu M H2O2 (R-2=0.9978, n=7) with a detection limit of 0.25 mu M. PMB modified electrodes was able to detect oxygen in river water with good sensitivity, selectivity and reproducibility.

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The photophysical properties such as electronic absorption, molar extinction coefficient, emission spectra, fluorescence quantum yield and lifetime of three different hydroxyflavones (a typical model of flavonols) such as: 3-HF, 3,6-diHF and 3,7-diHF, have been studied in the pH range from 2.5 to 9.2. Both electronic absorption and fluorescence spectra are sensitive to pH. The fluorescence quantum yield at pH 7.4 of the mentioned flavones probes have been determined. The fluorescence lifetime of different emissive species (Normal, Tautomer and Anion forms) as pH dependence have been also estimated. The effect of pH on the intramolecular excited state proton transfer process (ESIPT) has been discussed. The normal and tautomeric forms change as a function of pH, the normal one being more sensitive. The position of the -OH group on the second aromatic ring in the flavonol's structure has been also discussed. The results have relevance to compounds which have photoreactions accompanied by dual fluorescence. (C) 2013 Elsevier B.V. All rights reserved.

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Increased need for non-destructive investigation methods in archaeology has become a major issue since sampling is in most cases restricted in view of the importance or uniqueness of the objects. For this reason, preliminary investigation using non-destructive techniques was performed on five samples of amber beads obtained from different excavation and archaeological sites. The use of FTIR and micro-Raman analysis revealed the presence of carboxyl, peroxide, hydroxyl, and complex ester functional groups as well as single and double bonds in the structure of the studied resin varieties. Further analysis of the amber samples from both archaeological and geological types by XPS, XRF, and SEM showed the presence of sulfur and a wide range of trace elements on the surface of the analysed samples. Our results proved that the combination of structural-molecular and surface elemental techniques for amber characterisation provides a very useful and simple methodology for the description of geological and archaeological amber samples from different regions of Europe. (C) 2013 Institute of Chemistry, Slovak Academy of Sciences

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The paper presents the results of original research on improving tara tannin extract for ecologic tanning methods in the context of the newest global ecology concepts on reducing carbon consumption by using tannin resources that do not imply deforestation. The paper proposes processing tara tannin through extraction and concentration using micro filtration, ultrafiltration and reverse osmosis membranes, determining a reduction in the concentration of insoluble matter and an increase in the tannin concentration, without modifying tannin through hydrolysis. In the first part of the paper we present the optimal filtration parameters using filtration membranes and the characteristics of concentrated tanning extracts, compared to the initial products.

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Photophysical properties of five hydroxyflavones (HF) (some typical models of flavonols), (3 - HF, 6 - HF, 7-HF, 3, 6 - diHF and 3, 7 - diHF) were studied in homogeneous media by means of UV-vis and steady-state and time resolved fluorescence spectroscopies. Their absorption and fluorescence characteristics based on the flavonols structure are presented and discussed. It was found that the fluorescence of the flavonols depends on the nature of the solvent and on their molecular structure, especially on the position and the number of the -OH groups of the substituted phenyl ring. Attention is paid to the number of the -OH groups that influence the excited-state intramolecular proton transfer (ESIPT) process. The fluorescence quantum yield and the lifetime of the flavonols in heterogeneous media have been also determined. The results are discussed with relevance to the flavonols as sensitive fluorescence probe and to their microenvironments in the systems of biological interest and especially in a typical protein environment.

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Two enzymes, laccase and peroxidase, were immobilized on chloromethylated styrene-divinylbenzene copolymers supports functionalized with phosphonates ((RO)(2)PO) or mixed ammonium and phosphonium groups ( N+R3Cl-, P+Ph3Cl-). Phosphonates groups and quaternary ammonium salts were grafted on the gel-type copolymer by Michaelis-Becker polymer analogue reaction. Mixed polymer-supported ammonium and phosphonium salts were obtained by transquaternization of the ammonium groups to phosphonium group. The degrees of functionalization for obtained polymers were relatively high ensuring a sufficient concentration of active centers per unit mass of the copolymer. The obtained materials were characterized by thermal analysis, FTIR spectroscopy and SEM microscopy. The effects of OR1 and R2 radicals from phosphonate and respectively ammonium groups, as well as those of glutaraldehyde utilization on the immobilization yield and the catalytic properties of the supported enzymes were indicated. The activity of enzymes increased after immobilization and high immobilization yield was obtained for all the samples. The higher interaction of enzymes with support was indicated for mixed ammonium and phosphonium functions. A higher catalytic activity was obtained for peroxidase in oxidation of phenol and laccase in oxidation of anisole. The low effect of glutaraldehyde on enzyme activity reveals the strong interaction of enzyme with the polymer support, respectively with the functional groups.

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This study was meant to determine the inhibitory activity of tannins and flavonoid compounds from Geranium robertianum, Helleborus purpurascens and Hyssopus officinale plant polyphenol rich extracts against urease and α-chymotrypsin. The G. robertianum, H. purpurascens and H. officinale extracts were purified and concentrated by microfiltration and ultrafiltration. Phenolic compounds including flavonoids and tannins have been linked to many pharmacological activities. Thus, the polyphenolic content of the extracts was assessed by UV-Vis spectroscopy and HPLC. The concentrated extracts enriched in polyphenolic compounds (flavonoids, tannins and phenolic acids) showed a significant inhibition against urease from jack bean (over 90%), whereas in case of the α-chymotrypsin, they proved to have an inhibition below 54%. The results of this support the use of G. robertianum, H. purpurascens and H. officinale polyphenolic extracts as potential sources of urease inhibitors. Among the three plant extracts tested, H. officinale polyphenolic extracts exhibited a high inhibitory activity (92.67%) against urease and low inhibition (19.6%) against α-chymotrypsin and could be considered as possible remedy in ulcer treatment. © 2014 Informa UK Ltd.

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The aim of the present work was to develop a spectrofluorimetric method of analysis applicable to β-lactam antibiotic cefotaxime sodium from aqueous solutions. We found interest in developing a fluorimetric method, using a luminescence spectrometer. Cefotaxime sodium was analysed by derivatization with a specific fluorescent compound namely 4-fluoro-7-nitrobenzofurazan which is a fluorophore used in the detection of amines. The method developed proved to be suitable for this purpose. This method was applied in the controlled release, in phosphate buffer solutions (pH=7.4), of cefotaxime sodium from hybrids obtained by the immobilization of the antibiotic in MCM-41 nanoparticles. © 2009 Universitatea Politehnica Bucuresti.

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The paper presents the results of original research on improving tara tannin extract for ecologic tanning methods in the context of the newest global ecology concepts on reducing carbon consumption by using tannin resources that do not imply deforestation. The paper proposes processing tara tannin through extraction and concentration using microfiltration, ultrafiltration and reverse osmosis membranes, determining a reduction in the concentration of insoluble matter and an increase in the tannin concentration, without modifying tannin through hydrolysis. In the first part of the paper we present the optimal filtration parameters using filtration membranes and the characteristics of concentrated tanning extracts, compared to the initial products.

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1-[(4-nitrophenyl)methyl]-4,4'-bipyridinium (N-PMB) was synthesized by refluxing 4,4'-bipyridine and 4-nitrobenzylchloride. A stable film of 1-phenylmethyl-4,4'-bipyridine (PMB) was successfully electrografted on glassy carbon electrodes by the reduction of the diazonium moieties generated in situ. High antifouling ability was obtained for the PMB modified electrode which makes it a useful sensor device for environmental waters monitoring. The modified electrode was used as an amperometric sensor for mediated hydrogen peroxide detection at -0.5 V. The calibration curve was linear from 5 to 60 μM H2O2 (R2=0.9978, n=7) with a detection limit of 0.25 μM. PMB modified electrodes was able to detect oxygen in river water with good sensitivity, selectivity and reproducibility. © 2014 The Authors. Published by ESG.