Gabriela Paun
CS I - Centrul de Bioanaliză
Biografie
Cu o experiență de peste 25 de ani în cercetare, mi-am dezvoltat principalele competențe în domeniul aplicării proceselor membranare, cum ar fi microfiltrarea, ultrafiltrarea și nanofiltrarea, în diverse domenii precum biotehnologia, industria alimentară și domeniul fitofarmaceutic. Am lucrat în fractionarea și concentrarea de principii active din extracte de plante medicinale, realizând caracterizări calitative și cantitative ale acestora, determinând activitatea antioxidanta a extractelor și evaluând efectul inhibitor al acestora asupra unor enzime asociate cu disfuncționalitățile organismului uman.
De-a lungul carierei mele, am abordat și o altă direcție de cercetare, și anume obținerea de suporturi microporoase, inclusiv membrane și microparticule polimerice/compozite, pentru diverse aplicații.
Pe lângă experiența în cercetare, am dobândit și abilități organizatorice și manageriale solide în calitate de director și responsabil de proiecte de cercetare. Aceste aptitudini m-au ajutat să coordonez și să gestionez proiectele cu succes.
Publicatii
| Publication | Authors | Date | |
|---|---|---|---|
article
Antioxidant And Antidiabetic Activity Of Cornus Mas L. And Crataegus Monogyna Fruit Extracts |
Paun Gabriela; Neagu Elena; Albu Camelia; Alecu Andreia; Seciu-Grama Ana-Maria; Radu Gabriel Lucian | Molecules, 2024 | |
RezumatThe 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. |
|||
article
Evaluating The Antioxidant And Antidiabetic Properties Of Medicago Sativa And Solidago Virgaurea Polyphenolic-Rich Extracts |
Paun Gabriela; Neagu Elena; Alecu Andreia; Albu Camelia; Seciu-Grama Ana-Maria; Radu Gabriel Lucian | Molecules, 2024 | |
RezumatThe 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. |
|||
article
Hybrid Materials Obtained By Immobilization Of Biosynthesized Ag Nanoparticles With Antioxidant And Antimicrobial Activity |
Petcu Gabriela; Ciobanu Elena Madalina; Paun Gabriela; Neagu Elena; Baran Adriana; Trica Bogdan; Neacsu Andreea; Atkinson Irina; Bucuresteanu Razvan; Badaluta Alexandra; Ditu Lia Mara; Parvulescu Viorica | International Journal Of Molecular Sciences, 2024 | |
RezumatAg 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. |
|||
article
Valorization Of Bioactive Compounds From Lingonberry Pomace And Grape Pomace With Antidiabetic Potential |
Neagu Elena; Paun Gabriela; Albu Camelia; Radu Gabriel Lucian | Molecules, 2024 | |
RezumatIn recent years, increased attention has been paid to the recovery of bioactive compounds from waste and by-products resulting from the agro-industrial sector and their valorization into new products, which can be used in the health, food, or agricultural industry, as innovative and sustainable approaches to waste management. In this work, two of these by-products resulting from the fruit-processing industry were used for the recovery of bioactive compounds (polyphenols), namely lingonberry pomace (Vaccinium vitis-idaea) and grape pomace (Vitis vinifera). Two green extraction techniques were employed to obtain hydroalcoholic extracts (solvent: 50% EtOH, 10% mass): ultrasound-assisted extraction (UAE) and accelerated solvent extraction (ASE). The extracts were subjected to micro- and ultrafiltration processes, and further analyzed to determine the bioactive compound content through spectrophotometric (UV-Vis) and chromatographic (HPLC-PDA) methods. Additionally, the extracts exhibited significant enzyme inhibition, particularly against alpha-amylase and beta-glucosidase, suggesting potential anti-diabetic properties. The extracts characteristics, polyphenolic content, antioxidant capacity and enzyme inhibitory ability, were statistically compared, and significant differences were found between the two extraction methods. The grape pomace concentrated extracts showed a pronounced inhibitory activity on both analyzed enzymes compared to the lingonberry pomace concentrated extracts, closer to the standard used; e.g., IC50 alpha-amylase = 0.30 +/- 0.01 mu g/mL (IC50 acarbose = 0.3 +/- 0.01 mu g/mL), IC50 alpha-glucosidase = 0.60 +/- 0.01 mu g/mL (IC50 acarbose = 0.57 +/- 0.02 mu g/mL). These findings highlight the potential of agro-industrial residues as bioactive compound resources, with their valorization through application in food, nutraceutical, or pharmaceutical industries therefore contributing to the sustainable development and promotion of circular economy principles with the recovery of valuable inputs from plant by-products. |
|||
article
Applications Of Enzymes As Ecologic Alternatives In The Leather Industry; [Applications Des Enzymes Comme Alternatives Écologiques Dans L'Industrie Du Cuir]; [Aplicații Ale Enzimelor Ca Alternative Ecologice În Industria De Pielărie] |
Simion D.; Gaidǎu C.; Pǎun G.; Berechet D. | Leather And Footwear Journal, 2023 | |
RezumatThe 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. |
|||
article
Artemisia Abrotanum And Symphytum Officinale Polyphenolic Compounds-Rich Extracts With Potential Application In Diabetes Management |
Neagu Elena; Paun Gabriela; Albu Camelia; Eremia Sandra Ana-Maria Victoria; Radu Gabriel Lucian | Metabolites, 2023 | |
RezumatLately, 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. |
|||
article
Evaluation Of Antioxidant And Antidiabetic Activities Of Trigonella Foenum- Graecum Phytoestrogen-Rich Extracts |
Paun Gabriela; Neagu Elena; Albu Camelia; Apreutesei Oana Teodora; Radu Gabriel Lucian | Planta Medica, 2023 | |
Rezumat |
|||
article
In Vitro Assessment Of The Antidiabetic And Anti-Inflammatory Potential Of Artemisia Absinthium, Artemisia Vulgaris And Trigonella Foenum-Graecum Extracts Processed Using Membrane Technologies |
Neagu Elena; Paun Gabriela; Albu Camelia; Apreutesei Oana Teodora; Radu Gabriel Lucian | Molecules, 2023 | |
RezumatRecently, 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. |
|||
article
Innovative Technologies For Obtaining Structured Emulsions, Based On Sea Buckthorn Extract And Tensides; [Technologies Innovantes Pour L’Obtention D’Émulsions Structurées À Base D’Extrait D’Argousier Et De Tensioactifs]; [Tehnologii Inovatoare Pentru Obținerea Unor Emulsii Structurate Pe Bază De Extract De Cătină Și Tenside] |
Simion D.; Gaidău C.; Păun G.; Berechet D.; Constantinescu R. | Leather And Footwear Journal, 2023 | |
RezumatNew 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). |
|||
article
Obtaining New Bioemulsions Based On Lavender Extract And Surfactants; [L’Obtention De Nouvelles Bioémulsions À Base D’Extrait De Lavande Et De Tensioactifs]; [Obținerea Unor Noi Bioemulsii Pe Bază De Extract De Lavandă Și Surfactanți] |
Simion D.; Gaidău C.; Păun G.; Berechet D.; Constantinescu R. | Leather And Footwear Journal, 2023 | |
RezumatNew 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). |
|||