Search Results (506)

Salinization of olive orchards constitutes a front-line agronomic challenge for farmers, consumers, and the scientific community as food security, olive logistics, and land use become more unsustainable and problematic. Plantlets of two olive varieties (var. Kalamon and var. Koroneiki) were tested for their performance under soil saline conditions, in which L-methionine, choline-Cl, and L-proline betaine were applied foliarly to alleviate adverse effects. The ‘Kalamon’ variety ameliorated its photosynthetic rates when L-proline betaine and L-methionine were administered at low saline exposure. The stressed varieties achieved higher leaf transpiration rates in the following treatment order: choline-Cl > L-methionine > L-proline betaine. Choline chloride supported stomatal conductance in stressed var. Kalamon olives without this pattern, which was also followed by var. Koroneiki. Supplementation regimes created a mosaic of responses on varietal water use efficiency under stress. The total phenolic content in leaves increased in both varieties after exogenous application only at the highest levels of saline stress. None of the substances applied to olive trees could stand alone as a tool to mitigate salinity stress in order to be recommended as a solid agronomic practice. The residual exploitation of amino acids by the olive orchard microbiome must also be considered as part of an environmentally friendly, integrated strategy to mitigate salinity stress. Full article

The sustainable recovery of valuable metals such as Cu and Co from ores is a pressing need considering environmental and economic challenges. Therefore, this study evaluates the effectiveness of deep eutectic solvents (DESs) as alternative leaching agents for Cu and Co extraction. Four DESs were prepared using choline chloride (ChCl) as a hydrogen bond acceptor (HBA) and oxalic acid (OA), ethylene glycol (EG), urea (U) and thiourea (TU) as hydrogen bond donors (HBDs). Leaching experiments were conducted with DESs supplemented with 30 wt.% water at varying temperatures, various solid-to-liquid ratios, and time durations. The ChCl:OA DES demonstrated the highest leaching efficiencies among the DESs tested on pure CuO and CoO, achieving 89.2% for Cu and 92.4% for Co (60 °C, 400 rpm, 6 h, −75 + 53 µm particle size, and 1:10 solid-to-liquid ratio). In addition, the dissolution kinetics, analysed using the shrinking core model (SCM), showed that the leaching process was mainly controlled by surface chemical reactions. The activation energy values for Cu and Co leaching were 46.8 kJ mol⁻¹ and 51.4 kJ mol⁻¹, respectively, supporting a surface chemical control mechanism. The results highlight the potential of ChCl:OA as a sustainable alternative for metal recovery. Full article

Lithium-ion batteries (LiBs) are utilized in numerous applications due to advancements in technology, and the recovery of end-of-life (EoL) LiBs is imperative for environmental and economic reasons. Pyrometallurgical and hydrometallurgical methods have been used in the recovery of metals such as Li, Co, and Ni in the EoL LiBs. Hydrometallurgical methods, which have been demonstrated to exhibit higher recovery efficiency and reduced energy consumption, have garnered increased attention in recent research. Inorganic acids, including HCl, HNO₃, and H₂SO₄, as well as organic acids such as acetic acid and citric acid, are employed in the hydrometallurgical recovery of these metals. It is imperative to acknowledge the environmental hazards posed by these acids. Consequently, solvometallurgical processes, which involve the use of organic solvents with minimal or no water, are gaining increasing attention as alternative or complementary techniques to conventional hydrometallurgical processes. In the context of solvent systems that have been examined for a range of solvometallurgical methods, deep eutectic solvents (DESs) have garnered particular interest due to their low toxicity, biodegradable nature, tunable properties, and efficient metal recovery potential. In this study, the leaching process of black mass containing graphite, LCO, NMC, and LMO was carried out in a short time using the ternary DES system. The ternary DES system consists of choline chloride (ChCl), glycolic acid (GLY), and ascorbic acid (AA). As a result of the leaching process of cathode powders in the black mass without any pre-enrichment process, Li, Co, Ni, and Mn elements passed into solution with an efficiency of over 95% at 60 °C and within 1 h. Moreover, the kinetics of the leaching process was investigated, and Density Functional Theory (DFT) calculations were used to explain the leaching mechanism. Full article

In this study, the ultrasonic-assisted extraction of deep eutectic solvents (UADES) for tea polysaccharides was optimized, and their physicochemical properties and antioxidant activities were analyzed. The optimal DES comprised choline chloride (CC) and ethylene glycol (EG) in a molar ratio of 1:3, with a water content of 40%. The optimized condition was an extraction temperature of 61 °C, an ultrasonic power of 480 W, and an extraction time of 60 min. The UADES extraction rate of polysaccharides (ERP) was 15.89 ± 0.13%, significantly exceeding that of hot water (HW) extraction. The polysaccharide content in the UADES-extracted tea polysaccharides (UADESTPs) was comparable to that of hot-water-extracted tea polysaccharides (HWTPs) (75.47 ± 1.35% vs. 74.08 ± 2.51%); the UADESTPs contained more uronic acid (8.35 ± 0.26%) and less protein (12.91%) than HWTP. Most of the UADESTPs (88.87%) had molecular weights (Mw) below 1.80 × 10³ Da. The UADESTPs contained trehalose, glucuronic acid, galactose, xylose, and glucose, with molar ratios of 8:16:1:10. The free radical scavenging rate and total reducing power of the UADESTPs were markedly superior to those of the HWTPs. Moreover, the UADESTPs had a better alleviating effect on H₂O₂-induced oxidative injury in HepG2 cells. This study develops an eco-friendly and efficient extraction method for tea polysaccharides, offering new insights for the development of tea polysaccharides. Full article

Malva sylvestris L. is a herbaceous plant, distributed worldwide, rich in biological active compounds, and known for its health benefits. In this study, extracts from different parts (leaves, flowers, and roots) of this plant were prepared using green classic (70% ethanol) and natural deep eutectic solvents (NADESs) based on choline chloride and acetic acid (NADES1) or glycerol (NADES2). Their antioxidant, antibacterial (against B. cereus, S, aureus, E. coli, and P. aeruginosa), and antifungal activity (against P. chrysogenum, F. oxysporum, A. parasiticus, A. flavus, A. niger A. carbonarius, and A. ochraceus) were compared. Ethanolic extracts were characterized with the highest total contents of phenols, flavonoids, and condensed tannins. Ethanolic and NADES flower extracts were the richest in the antioxidants tested. Alkaloids were extracted in low quantities. The experimentally determined antioxidant potential of the extracts proved the highest DPPH scavenging activity of ethanolic extracts and the lowest of NADES1 extracts. The ABTS scavenging capacity of NADES1 and ethanolic extracts displayed comparable results, while NADES2 extracts were characterized as having the highest FRAP activity. NADES1 extracts manifested pronounced antibacterial activity, partially due to the low pH of the pure solvent, as well as inconsistent antifungal activity—from moderate to a complete lack of activity. A strong positive correlation was reported between the DPPH radical scavenging capacity and phenolic compound content. Future detailed investigations on the mechanism of the antimicrobial activity of NADES1 extracts are necessary to clarify the observed phenomenon of the decreased antifungal potential of NADES1 extracts compared to the pure solvent NADES1. Full article

Microbial contamination of hatching eggs often leads to reduced hatchability and poor chick quality. As trimethylamine (TMA), a metabolite derived from dietary choline, has antimicrobial properties, increasing yolk TMA contents may increase bacterial resistance to eggs; however, the effects of TMA concentrations on chick quality remain unknown. Hence, this study was conducted to determine the effects of yolk TMA concentrations on the hatchability and chick quality of dwarf hens with different FMO3 genotypes. Hens (n = 140) were divided into control and experimental groups; the latter received choline chloride (2800 mg/kg) to elevate their yolk TMA concentrations. The TMA content, Pasgar score, hatchability, and post-hatching performance were evaluated. The results showed that choline supplementation significantly increased TMA concentrations in hens with AT and TT genotypes. Higher yolk TMA concentrations (≥4 µg/g) correlated with improved Pasgar scores and reduced abnormalities in vitality, navel, and yolk sac absorption. Hatchability peaked at 6.49 µg/g TMA, suggesting a threshold effect. Although the growth rate remained unaffected, chick mortality decreased in the high-TMA group. Therefore, moderate TMA concentrations can enhance egg antimicrobial defenses and improve reproductive performance. This strategy provides a biologically grounded alternative to traditional chemical disinfection in hatcheries. Full article

The cigarette production from Nicotiana tabacum generates significant amounts of waste, with an estimated 68.31 million tons of pre- and post-harvest waste discarded annually. The pre-harvest waste includes the upper parts of the plant, inflorescences, and bracts, which are removed to help the growth of the lower leaves. This study explores the potential of apical leaves from Nicotiana tabacum var. Virginia, discarded during the budding stage (pre-harvest waste). The leaves were extracted using environmentally friendly solvents (green solvents), including distilled water (DW) and two natural deep eutectic solvents (NaDESs), one consisting of simple sugars, fructose, glucose, and sucrose (FGS) and the other consisting of choline chloride and urea (CU). The anti-inflammatory and anti-aging potential of these green extracts was assessed by the inhibition of key enzymes related to skin aging. The xanthine oxidase and lipoxygenase activities were mostly inhibited by CU extracts with IC₅₀ values of 63.50 and 8.0 μg GAE/mL, respectively. The FGS extract exhibited the greatest hyaluronidase inhibition (49.20%), followed by the CU extract (33.20%) and the DW extract (20.80%). Regarding elastase and collagenase inhibition, the CU extract exhibited the highest elastase inhibition, while all extracts inhibited collagenase activity, with values exceeding 65%. Each extract had a distinct chemical profile determined by LC-ESI-QTOF-MS/MS and spectrophotometric methods, with several shared compounds present in different proportions. CU extract is characterized by high concentrations of rutin, nicotiflorin, and azelaic acid, while FGS and DW extracts share major compounds such as quinic acid, fructosyl pyroglutamate, malic acid, and gluconic acid. Ames test and Caenorhabditis elegans assay demonstrated that at the concentrations at which the green tobacco extracts exhibit biological activities, they did not show toxicity. The results support the potential of N. tabacum extracts obtained with NaDESs as antiaging and suggest their promising applications in the cosmetic and cosmeceutical industries. Full article

In this study, CGMCC NO:28566, a strain that can efficiently convert Ethyl 4-chloroacetoacetate(COBE) to (R)-4-chloro-3-hydroxybutyrate((R)-CHBE), was screened by soil-sieving bacteria. In order to improve the transformation effect of the strain, the natural low-eutectic solvent (NADES), which can alter the cell permeability, was utilized for assisted catalysis, and a better catalytic effect was achieved. This study was carried out using a co-culture of strains with NADES and secondary addition of NADES on the basis of co-culture, and 10 NADESs were screened at the same time. The co-catalytic effect of 0.5% (w/v) choline chloride: urea (1:2) (ChCl:U (1:2)) was found to be the most significant, with a yield of (R)-CHBE reaching 89.1%, which was 58.2% higher than that of the control group, with a 99% ee value. Furthermore, the catalytic results demonstrated that the co-culture of the strain with NADES during fermentation yielded superior outcomes to the secondary addition of NADES during the reaction buffer. Furthermore, the catalytic effect of ChCl:U (1:2) was demonstrated to be superior to that of its individual components or single-component blends, due to its distinctive valence bonding advantage. The results indicate that the addition of 0.5% (w/v) ChCl:U (1:2) during the co-culture process has the effect of improving cell permeability to a certain extent, thereby increasing the contact between the substrate and the enzyme during the whole-cell catalytic reactions. Full article

Utilizing deep eutectic solvents (DESs) combined with microwave-assisted extraction (MAE) provides a sustainable method for extracting bioactive compounds from the macroalgae Ascophyllum nodosum and Laminaria hyperborea. Two DES formulations, choline chloride/lactic acid (ChCl/LA) and sodium acetate/lactic acid (AcNa/LA), were evaluated under varying extraction conditions. For L. hyperborea, ChCl/LA at 150 °C for 10 min yielded a total phenolic content (TPC) of 15.34 mg GAE/g DW, with antioxidant activities measured by DPPH (34.55 mg TE/g DW) and ABTS (27.06 mg TE/g DW). Extending the extraction to 20 min at 130 °C increased the TPC to 19.12 mg GAE/g DW. A. nodosum exhibited higher bioactivity, with the TPC reaching 47.51 mg GAE/g DW under the same conditions. High-performance liquid chromatography (HPLC) identified significant phenolics such as 3,4-dihydroxybenzoic acid (678.05 µg/g DW) and vanillin (6718.5 µg/g DW). Antimicrobial assays revealed strong inhibition (zones > 20 mm) against Clostridium perfringens, moderate activity against Staphylococcus aureus, and selective activity against Escherichia coli. FT-IR confirmed the presence of phenolics, polysaccharides, and lipids. Thermal and structural characterization revealed that A. nodosum residue showed an amorphous structure, while L. hyperborea retained crystallinity with decomposition profiles indicating potential bioenergy potential. SEM images revealed significant cell wall disruption correlating with extraction efficiency. These results demonstrate DES–MAE as an effective, green strategy for producing high-value algal extracts and valorizing residual biomass for biotechnological applications. Full article

The electrochemical behavior of copper (II) on glassy carbon from an eutectic mixture of choline chloride (ChCl) and ethylene glycol (EG) was investigated using cyclic voltammetry (CV). The redox and deposition processes were studied for electrolyte concentrations of 0.01 M and 0.5 M Cu(II), with particular attention paid to the effects of different Cu(II) concentrations on the copper deposition potential and morphology of the copper deposits. The CV results showed that the Cu(II) species are reduced to Cu(0) via two separate steps. Higher Cu(II) concentrations in the electrolyte triggered the formation of differently coordinated Cuⁿ⁺ complexes next to the electrode, which shifted the electrodeposition potential of Cu(I)/Cu(0) couples towards more positive values. The Cu deposits were obtained potentiostatically from 0.01 M and 0.5 M Cu(II)-ChCl:EG electrolyte and analyzed using scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction. The different copper concentrations in electrolytes induced different morphologies of electrodeposited copper, where the mixture of irregular grains and carrot or needle-like dendrites was obtained from 0.01 M, and rose-like forms were obtained from 0.5 M electrolytes. This study is the first to identify these rose-like forms and the mechanism of their formation, which is discussed in detail. Full article

Background/Objectives: Solvent-intensive methods are traditionally required to extract curcumin, a potent bioactive compound from Curcuma longa, raising environmental and safety concerns. Methods: This study introduces an efficient and scalable extraction approach using microwave–ultrasound-assisted extraction (MUAE) combined with a natural deep eutectic solvent (NADES) composed of choline chloride and lactic acid. Process parameters, including solvent water content (20–30% v/v) and solid loading (4–8% w/v), were optimized using response surface methodology (RSM) to enhance curcumin yield. Results: Under optimal conditions (20% water content and 8% solid loading), the MUAE method achieved a curcumin content of 40.72 ± 1.21 mg/g, representing a 14.36% improvement over conventional ultrasound-assisted extraction (UAE), while reducing solvent usage by 50%. The quadratic model demonstrated excellent predictive capability, with an R² value of 0.98. In addition, anti-solvent precipitation using water increased curcuminoid purity from 0.31% to 20.54%, with a recovery rate of 21.49%. Conclusions: Mechanistic analysis revealed that microwave-induced cell disruption, ultrasound cavitation, and the modulation of NADES viscosity contributed synergistically to the enhanced extraction performance. This study is the first to combine MUAE with NADES for optimized curcumin extraction, delivering both high yield and reduced solvent consumption. The proposed method offers a sustainable and industrially relevant alternative for curcumin recovery in the food, nutraceutical, and pharmaceutical sectors. Full article

Natural deep eutectic solvents (NADESs) have emerged as a promising eco-friendly alternative to petrochemicals for extracting plant metabolites. Considering that the demand for sustainable “green” ingredients for industrial applications is growing, those solvents are purported to develop extracts with interesting phytochemical fingerprints and biological activities. Given the interest in flavonoids from Chenopodium quinoa Willd. leaves, an efficient “green” extraction method was developed by investigating eight NADESs with defined molar ratios, i.e., malic acid-choline chloride (chcl)-water (w) (1:1:2, N1), chcl-glucose-w (5:2:5, N2), proline-malic acid-w (1:1:3, N3), glucose-fructose-sucrose-w (1:1:1:11, N4), 1,2-propanediol-chcl-w (1:1:1, N5), lactic acid-glucose-w (5:1:3, N6), glycerol-chcl-w (2:1:1, N7), and xylitol-chcl-w (1:2:3, N8). Rheological measurements of all NADESs confirmed their pseudoplastic behaviors. To improve the extraction processes, differential scanning calorimetry (DSC) allowed us to determine the maximum amount of water that could be added to the most stable NADES (N1, N2, N3, and N4; 17.5%, 20%, 10%, and 10% w/w, respectively) to lower their viscosities without disturbing their eutectic environments. The phytochemical compositions of NADES extracts were analyzed using high-performance thin-layer chromatography (HPTLC), and their free radical scavenging and α-amylase inhibitory properties were assessed using HPTLC-bioautography. N2, diluted with 20% of water, and N7 presented the best potential for replacing methanol for an eco-friendly extraction of flavonoids, radical scavengers, and α-amylase inhibitors from quinoa leaves. Their biological properties, combined with a good understanding of both thermal behavior and viscosity, make the obtained quinoa leaf NADES extracts good candidates for direct incorporation in nutraceutical formulations. Full article

In this study, polyvinyl alcohol (PVA) films were reinforced with lignocellulosic nanofibers (LCNFs) extracted from bamboo shoot shells using a choline chloride-based deep eutectic solvent (DES). A filler loading of 10 wt% was identified as the optimal condition for enhancing film performance. To improve interfacial compatibility between the PVA matrix and LCNFs, three surface modification treatments were applied to the nanofibers: hydrochloric acid (HCl) hydrolysis, citric acid (CA) crosslinking, and a dual modification combining both methods (HCl&CA). Among all formulations, films incorporating dual-modified LCNF at 10 wt% loading exhibited the most significant improvements. Compared to neat PVA, these composites showed a 79.2% increase in tensile strength, a 15.1% increase in elongation at break, and a 33.1% enhancement in Young’s modulus. Additionally, thermal stability and barrier properties were improved, while water swelling and solubility were reduced. Specifically, the modified films achieved a thermal residue of 9.21% and the lowest degradation rate of 10.81%/min. Water vapor transmission rate and oxygen permeability decreased by 18.8% and 18.6%, respectively, and swelling and solubility dropped to 14.26% and 3.21%. These results highlight the synergistic effect of HCl hydrolysis and CA crosslinking in promoting uniform filler dispersion and strong interfacial adhesion, offering an effective approach to valorizing bamboo shoot shell waste into high-performance, eco-friendly packaging materials. Full article

Environmentally friendly extraction technologies for biologically active substances (BASs) are an actively developing and important industry. In recent years, the development of this area has been associated with the use of low-melting mixtures, which are most often referred to as “deep eutectic solvents”. Vaccinium vitis-idaea L. is a valuable source of phenolic biologically active compounds. However, to date, there are limited studies devoted to the use of such solvents for the extraction of biologically active substances from V. vitis-idaea. This study introduces the use of low-melting mixtures of choline chloride or betaine with lactic acid and water for the ultrasonic extraction of phenolic secondary metabolites from V. vitis-idaea leaves for the first time. The kinetics of extraction have been studied, and the extraction conditions have been optimized using a Box–Behnken design. It was found that the optimal extraction conditions are follow: the most suitable mixture is betaine with lactic acid and water at a molar ratio of 1:10:5, the optimal temperature is 33 °C, and the optimal ratio of the mass of plant material to the volume of the solvent is 1:20. Under these conditions, the yield of total phenolic compounds was 744.3 ± 1.2 mg GAE/g, and total flavonoids reached 24.4 ± 0.2 mg RE/g. The IC₅₀ values of the obtained extract were 2.45 mg/mL for free radical scavenging with DPPH and 3.47 mg/mL for ABTS. The data obtained can be used in the development of green technologies for the extraction of biologically active substances from the leaves of V. vitis-idaea. Full article

Natural deep eutectic solvents (NaDESs) are emerging solvents for their yield when used for extraction of different molecules, including polyphenols. NaDESs are a cutting-edge technology that offers numerous advantages, including cheap cost, safety, effectiveness and environmental friendliness. However, due to NaDES’ high boiling point, the recovery and separation of compounds after the extraction is the bottleneck of the process. In this work, two affordable methods were tested for the recovery of phenolic compounds from three binary NaDESs (composed of choline chloride mixed separately with lactic acid, tartaric acid or glycerol as hydrogen bond donors): the antisolvent and the liquid–liquid extraction methods. The former was assessed by diluting the extracts with different aliquots of water, employed as antisolvent, which was ineffective. For the liquid–liquid extraction method, ethyl acetate (EtOAc), acetonitrile (ACN), 2-chlorobutane (2-CB) and 2-methyltetrahydrofuran (2-MeTHF) were compared. Except for ACN, all solvents were perfectly immiscible with the three NaDESs, forming biphasic systems that were analyzed by colorimetric assays and HPLC/MS. 2-MeTHF applied on a 10-fold water dilution of the NaDES extract reached recovery percentages higher than 90% for most of the non-anthocyanin phenols and good recovery (up to 80%) for some anthocyanins. 2-MeTHF appears to be the first known solvent capable of extracting anthocyanins from NaDESs. Finally, a two-step liquid–liquid extraction performed firstly with EtOAc and subsequently with 2-MeTHF is proposed for the separation of different phenolic fractions. Full article