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Nowadays, intensive agriculture correlated with the impact of climate change has led to nutrient soil depletion and the salinization of agricultural lands, making them unsuitable for conventional agricultural crops, with a direct impact on the food industry. Therefore, it is necessary to find sustainable alternative solutions that satisfy the needs of both consumers and food production. One such solution may be represented by salt-tolerant species that can fulfill food requirements. One of the most promising salt-tolerant plant species that can be used is Salicornia europaea L. The present work was conducted in greenhouse conditions, and the adaptability of the species on different cultivation substrates was investigated by means of monitoring the plant indicators such as cuticle, epidermis, parenchyma, polyphenols content, and minerals. Moreover, the correlation between the polyphenol and mineral contents was highlighted. Therefore, three cultivation substrates with different levels of salinity/electrical conductivity were used. The reference (I) for biochemical indicators was represented by the plant grown in natural salinity conditions in the Southeast region of Romania. The results indicate that Salicornia europaea L. can be grown on different cultivation substrates other than salted soils, the plant showing the capacity to accumulate bioactive compounds similar to natively grown ones.

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The aim of this work is to optimize the supercritical liquefaction process of rapeseeds in order to produce a bio-oil with low viscosity. Reaction parameters, such as reaction temperature, residence time, and solvent to biomass ratio, were studied. Response surface methodology (RSM) based on central composite design (CCD) was used to determine the optimum operating conditions to minimize the bio-oil viscosity. The low bio-oil viscosity of 5.90 mPa.s was obtained at the optimal operating conditions of 280 degrees C, 40 min, and methanol/biomass mass ratio of 5.5/1, at pressure within the batch reactor of 124.59 bars. At these optimal conditions, the bio-oil yield was high and reached around 80wt%, while its heating value was about 38.36MJ/kg. It was proved that the reaction temperature and methanol/biomass ratio were the most influencing parameters on bio-oil viscosity according to the ANOVA results. The predicted values from the RSM model was in good agreement with the experimental results. The GC-MS analysis showed that the bio-oil is mainly composed of methyl esters, which are the main components of biodiesel. This study revealed the complete supercritical transesterification of lipid into alkyl esters resulting in a low amount of triglycerides, monoglycerides, diglycerides, and glycerin, identified by GC-FID. The results will provide useful guidance for predicting other physical properties of bio-oil following a similar methodology to that used in this work. In addition, bio-oil could be used for biodiesel fuel production but after hydrodeoxygenation treatment.

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New global directions align agricultural land resources towards food production; therefore, marginal lands could provide opportunities for second-generation energy crops, assuming that in the difficult conditions of plant development, productivity can be maintained at relatively high levels. Sustainable bioenergy production on marginal lands represents an ambitious objective, offering high-quality biofuels without competing with the agri-food industry, since it allows successful feedstock production to be performed on unmanaged areas. However, marginal land feedstock production generally shows several agronomic, techno-economic, and methodological challenges, leading to decreases in the obtained quantities of biomass and profitability. Sweet Sorghum is a technical plant that has the needed qualities to produce large amounts of biofuels on marginal lands. It is a high biomass-and sugar-yielding crop, characterized by a high photosynthetic efficiency and low fertilizer requirement, is resistant to drought, and adapts well to different climate areas. Marginal lands and contaminated soils provide a favorable development environment for plants such as sweet sorghum; however, in-depth research studies on biomass productivity must be carried out, as well as advanced quality evaluation of the products, in order to develop combined technologies that use resources efficiently. The present study starts with a comparative evaluation of two sweet sorghum crops established on both marginal and regular lands, assessing plant development characteristics and juice production, and an evaluation of bioethanol generation potential. The vegetal wastes resulting from the processing were treated by pyrolysis, with the aim of maximizing the productivity of high-quality liquid biofuels and chemicals. The charcoal obtained in the thermal processes was considered as an amendment of the soil so that marginal land quality could be improved over time. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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This paper aimed to investigate the conversion of sunflower seeds to bio-char through hydrothermal liquefaction (HTL) process. The effect of reaction temperature (X-1, 240-320 degrees C), residence time (X-2, 10-60 min) and biomass/solvent ratio (X-3 , 20-80%) was analyzed and optimized using full factorial design of response surface methodology. The developed regression model gave accurate predictions and fitted well with the experimental results with a determination coefficient R-2 of 92.89%. The optimized conditions for bio-char production have been found to be 240 degrees C, 60 min and 20%, temperature, time and biomass to solvent ratio, respectively. These optimum values were validated by experimental runs which produced a bio-char yield of 32.24 wt% with higher heating value of 32.24 MJ/kg and high carbon content of 65.45%. The quadratic model revealed a strong interaction between reaction temperature and residence time, as well as, reaction temperature and biomass/solvent ratio. Based on the thermal decomposition mechanism of bio-char, derivative thermogravimetry revealed two major peaks were observed at 275 and 400 degrees C indicating the improvement in thermal stability of the bio-char after HTL process. In addition, the obtained bio-chars were different in terms of their organic and ash content depending on the HTL operating conditions.

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The paper presents the biological variation in biochemical compounds of fruits belonging to Ribes nigrum L. species during the maturation process. The fruits from two varieties were collected in the following phenological stages: early first fruits (SIII), advanced first fruit (SIV), harvesting maturity (SV), and consumption maturity (SVI). The extracts were subjected to analysis. Total phenolic content (TPC) expressed as gallic acid equivalent (GAE), total flavonoid content (TFC) expressed as rutin equivalent (RE), and free radical scavenging activity (FRSA) expressed as mg/mL ascorbic acid equivalent (AAE), and gas-chromatographic profile were determined. The phenolic content differed considerably during the maturation process. Thus, the maximum value of TPC was achieved by 'Kzvana' fruits in the SV stage with 7.36 mM GAE/ml extract. The flavonoid content was highlighted in 'Roxia' fruits in the SVI stage with 1.24 mM RE/mL extract. With regard to FRSA, 'Kzvana' fruits have better activity. Also, the aromatic profile was characterized using gas chromatographic analysis.

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Bio-oil production from sunflower seeds, as model components, was carried out in supercritical hydrothermal liquefaction conditions. The effects of operating parameters such as temperature, time, and biomass/solvent mass ratio were investigated. Response surface methodology based on full factorial design was utilized to optimize the operating conditions using Design Expert software. From the analysis of variance, the most influential factor of each experimental design response was identified and a regression model was derived. The results show that the quadratic polynomial model provided accurate predictions for bio-oil yield and its viscosity, with a determination coefficient R-2 of 0.9120 and 0.9351, respectively. The optimum condition was 286.21 degrees C, a reaction time of 12 min, and 20% of biomass/solvent mass ratio. These conditions led to obtain 79.96 wt.% of bio-oil with a viscosity of 18.09 mPa s. The produced bio-oil was subjected to different analyses and characterized by gas chromatography-mass spectrometry. Besides, ether esters were identified as major components. Bio-oil properties were evaluated according to standard norms, and the results suggest the need of further upgrading step to improve its quality.

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Currently, the entire world is facing major challenges related to agricultural practices and heavy metals contaminations of agricultural systems and food production. On the other hand, the structure, texture, and properties of the soil have deteriorated as a result of intensive conventional agriculture based on the addition of different inputs. Along with these, toxic metals affect agricultural soils, crops, food chain, becoming a major threat to living systems. Among these is chromium (Cr), an element naturally occurring in rocky soils and volcanic dust. The increased use of chromium in several multiple activities causes soil and water contamination. Differently from other heavy metals like lead, cadmium, and copper, chromium presents different degrees of toxicity depending on its chemical form. In the present review, we present data regarding chromium abundance in agricultural systems, factors favouring the absorption in the plant and bioaccumulation in different organs and tissues, bioaccumulation and translocation factors, its toxicity in plants, animals, and human through the food chain, and how it can be quantified using different types of analysis.