Natural Deep Eutectic Solvents Research Articles

Exploiting of novel natural reactive deep eutectic solvents in the sustainable synthesis and tuning the coating’s properties of antibacterial polyurethane coatings

Exploiting of novel natural reactive deep eutectic solvents in the sustainable synthesis and tuning the coating’s properties of antibacterial polyurethane coatings

Valorization of Sour Cherry Kernels: Extraction of Polyphenols Using Natural Deep Eutectic Solvents (NADESs).

The objective of this research was to optimize the natural deep eutectic solvent (NADES) extraction process from sour cherry kernels (Prunus cerasus L.). For polyphenol isolation, conventional solid-liquid extraction was employed using different concentrations of ethanol (0, 10, 20, 30, 40, 50, 60, 70, 80, 90, and 96%), as well as the innovative NADES extraction technique. In the initial phase of the research, a screening of 10 different NADESs was conducted, while extraction was carried out under constant parameters (50 °C, 1:20 w/w, 60 min). NADES 4, composed of lactic acid and glucose in a molar ratio of 5:1, exhibited the highest efficiency in the polyphenol isolation. In the subsequent phase of the research, response surface methodology (RSM) was utilized to optimize the extraction process. Three independent variables, namely temperature, extraction time, and solid-liquid (S/L) ratio, were examined at three different levels. The extracted samples were analyzed for total phenol (TP) and antioxidant activity using the DPPH, ABTS, and FRAP assays. ANOVA and descriptive statistics (R2 and CV) were performed to fit the applied model. According to RSM, the optimal extraction conditions were determined as follows: temperature of 70 °C, extraction time of 161 min, and S/L ratio of 1:25 w/w.

Extraction of chitin-glucan complex from shiitake (Lentinula edodes) fruiting bodies using natural deep eutectic solvents and its prebiotic potential

Chitin-glucan complex (CGC) is an emerging novel prebiotic with numerous physiological activities in amelioration of clinical manifestations. In the present work, natural deep eutectic solvent (NADES), ultrasonication, and submerged fermentation using probiotic microorganisms were deployed for the extraction of CGC from Shiitake fruiting bodies. CGC obtained through non-ultrasonication assisted fermentation employing Lactiplantibacillus plantarum exhibited maximum polysaccharide yield (27.86 ± 0.82 % w/w). However, based on antioxidant potential, NADES combination of urea: glycerol (1:1 M ratio) was selected for further characterization. The rheological behavior of CGC under optimized conditions showed shear thinning property in both 0.1 M NaCl and salt-free solution. FTIR, 1H-(1D), and 2D 1H1H Homonuclear NMR spectra displayed distinctive patterns associated with β-glycosidic linkage and β-d-glucopyranose sugar moiety. XRD profiles of CGC exhibited characteristic peaks at 2θ = 23°, 25°, and 28° with corresponding hkl values of (220), (101), and (130) lattice planes, respectively. Enhanced radical scavenging activities were noticed due to the triple helical structure and anionic nature of CGC. CGC exhibited potential prebiotic activity (prebiotic score 118–134 %) and short chain fatty acids liberation (maximum 9.99 ± 0.41 mM by Lactobacillus delbrueckii). Simulated static in-vitro digestion demonstrated that CGC withstands acidic environment of gastric phase, which indicated its suitability for use as a prebiotic in nutraceutical-enriched food products.

Olive tree leaves as a great source of phenolic compounds: Comprehensive profiling of NaDES extracts

Waste from the olive industry is a noticeable source of antioxidant compounds that can be extracted and reused to produce raw materials related to the chemical, cosmetic, food and pharmaceutical sectors. This work studies the phenolic composition of olive leaf samples using liquid chromatography with ultraviolet detection coupled to mass spectrometry (LC-UV-MS). Olive leaf waste samples have been crushed, homogenized, and subjected to a solid-liquid extraction treatment with mechanical shaking at 80 °C for 2 h using Natural Deep Eutectic Solvents (NaDES). The phenolic compound identification in the resulting extracts has been carried out by high-resolution mass spectrometry (HRMS) using data-dependent acquisition mode using an Orbitrap HRMS instrument. >60 different phenolic compounds have been annotated tentatively, of which about 20 have been confirmed from the corresponding standards. Some of the most noticeable compounds are oleuropein and its aglycone and glucoside form, luteolin-7-O-glucoside, 3-hydroxytyrosol, and verbascoside.

Optimization of Extraction of Four Components from Radix Scrophulariae with Natural Deep Eutectic Solvents and Evaluation of Extract’s Antioxidant Activity

Optimization of Extraction of Four Components from Radix Scrophulariae with Natural Deep Eutectic Solvents and Evaluation of Extract’s Antioxidant Activity

Natural Deep Eutectic Solvents (NADES): Manufacture, Characteristics, and Their Significance as Designer Solvents

AbstractTo replace the hazardous organic solvents currently in use, one of the key objectives of green chemistry has been the development of green solvents obtained from natural sources. Natural deep eutectic solvents (NADES) are bio‐based natural compounds, namely primary metabolites like organic acids, sugar, alcohols, amines, and amino acids, which are acceptable to the environment and may eventually replace the conventionally used harsh organic solvents. This study focuses on the recent developments in the realm of these innovative materials as well as the conventional deep eutectic solvents (DES)‐based techniques. A more in‐depth examination of DES's applications in various chemical processes is covered after a description of its definition, manufacture, and unique characteristics. Their significance as designer solvents in various organic reactions and their impact on production methods are addressed.

Extraction of phenolic compounds from lucuma (Pouteria lucuma) seeds with natural deep eutectic solvents: modelling using response surface methodology and artificial neural networks

The present study aimed to extract polyphenolic compounds from lucuma (Pouteria lucuma) seeds using natural deep eutectic solvents (NADES) as a green, efficient, and environmentally friendly extraction. This was optimized by using the Response Surface Method (RSM) and comparing its predictive capacity with Artificial Neural Networks (ANN) and Convolutional Neural Networks (CNN). Four NADES were prepared by mixing lactic acid (LA) with each of the following reagents: sodium acetate (SA), urea (U), glucose (G), and ammonium acetate (AA), separately. The yield of total phenolic compounds (TPC) obtained from lucuma seeds with each NADES was measured as an optimization criterion with the Box-Benhken design. The following factors were evaluated: time, temperature, and the lucuma seed flour (LSF): NADES ratio. The response variables were TPC and antioxidant activity. The LA-AA extract was selected because it exhibited the highest TPC value and was analyzed by UHPLC–MS (Ultra-performance Liquid Chromatography-Mass Spectrometry). From the RSM, the optimal extraction parameters were 80 min, 52°C, and LSF: NADES ratio of 8:100 (w/v), obtaining a TPC value of 3601.51 ± 0.51 mg GAE/100 g LFS. UHPLC–MS analysis evidenced the formation of epigallocatechin isomers from epigallocatechin gallate. The predictive ability of ANNs compared to RSM was demonstrated.

Green Method Comparison and Optimization of Anthocyanin Recovery from "Sangiovese" Grape Pomace: A Critical Evaluation of the Design of Experiments Approach.

Grape pomace is the main by-product obtained from wine production that is still enriched in bioactive compounds. Within a framework of waste/by-product reuse through a sustainable approach, various green methods were utilized in this work to recover anthocyanins from the pomace resulting from "Sangiovese" grape vinification. Ultrasound- and Microwave-Assisted Extractions (UAE and MAE) were coupled with the use of green solvents, such as acidified water, an ethanol/water mixture, and Natural Deep Eutectic Solvents (NaDES), and their efficacy was compared with that of a conventional method based on a methanol/acidified water mixture. The Total Anthocyanin Index ranged from 36.9 to 75.2 mg/g DW for UAE, and from 54.4 to 99.6 mg/g DW for MAE, while resulting in 47.1 mg/g DW for conventional extraction. A Design of Experiments (DoE) approach was applied to MAE, the most efficient technique. Temperature, time, and the solid-to-liquid ratio were set as X variables, while malvidin-3-O-glucoside content and antioxidant activity were used as response variables, measured by High-Performance Liquid Chromatography with Diode Array Detection (HPLC-DAD) and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay, respectively. The correlation between temperature and time and the antioxidant activity of the extract was positive, while it was found to be negative when considering malvidin-3-O-glucoside concentration as a response variable. Thus, the optimal conditions in temperature, time and solid-to-liquid ratio were different depending on the chosen variable. The results underline the importance of selecting an accurate response when using the response surface methodology approach.

Eco-friendly extraction of six different rosemary (Rosmarinus officinalis L.) genotypes-using natural deep eutectic solvents: Optimization and modeling via response surface methodology (RSM)

New environmentally friendly extraction methods and solvents such as ultrasound assisted extraction (UAE) and natural deep eutectic solvents (NADES) are replacing the traditional extraction methods with organic solvents. In the present study, NADES prepared with choline chloride 1,2-propylene glycol (ChCl-PG) were characterized and running parameters for the UAE process of phenolics were optimized and modeled with response surface methodology (RSM) using ChCl-PG. The optimum conditions obtained from running parameters were used to compare efficiency of NADES with four traditional solvents and NADES was found to be for phenolics extraction from rosemary. Experimental data was used to maximize extraction yields of phenolics and antioxidant activities, rosmaranic acid, chlorophyll and carotene content using six rosemary genotypes under optimal conditions with NADES and a traditional solvent (ethanol:water, 80:20 v/v) with UAE. Rosemary genotypes showed significant differences for bioactive compound yields except chlorophyll and carotene content. NADES and traditional solvents did not affect rosmarinic acid and carotenoid yield, but extraction yield of other compounds and their antioxidant capacities were significantly affected by the solvent. While rosmarinic acid content was not affected, chlorophyll and carotenoid contents were affected by the solvent type. Out of 21 Pearson correlation coefficients, 5 and 7 had significant positive correlations between traditional and NADES solvents, respectively. Results showed that NADES with UAE is an effective method could be used for extraction of secondary compounds.

Biorefinery approach with green solvents for the valorization of Citrus reticulata leaves to obtain antioxidant and anticholinergic extracts

Citrus reticulata L leaves are one of the main post-harvest byproduct, containing bioactive compounds, that are usually undervalued. This work describes the development of a biorefinery process based on the application of supercritical CO2 (SC-CO2) followed by ultrasonic-assisted extraction (UAE) combined with Natural Deep Eutectic Solvents (NaDES) to extract bioactive terpenoids and phenolic compounds from these leaves. Extraction temperature and pressure of SC-CO2 were optimized, obtaining the highest bioactive terpenoids content using 200 bar at 60 °C. A Box-Behnken experimental design showed that 57% of water in NaDES composed of Choline Chloride and Glycerol (1:2) as extraction solvent at 25 °C for 50 min were the optimal UAE-NaDES extraction conditions to obtain the highest bioactive phenolic content from the residue of the optimal SC-CO2 extraction. The optimum extract presented the highest bioactivity and polyphenol content determined by LC-DAD-MS compared with extracts obtained using only water or NaDES as solvent.

Anti-Inflammatory and Anti-Arthritis Activity of Quercetin: A Comprehensive Review.

This comprehensive exploration delves into the multifaceted attributes of quercetin, a flavonoid with extensive health-promoting potential. The review navigates through its fundamental properties, encompassing its chemical structure, classification as a flavonoid, and its natural prevalence in various sources. Addressing solubility, stability, and bioavailability challenges, the investigation delves into innovative isolation techniques, including solvent extraction, solid-phase extraction, natural deep eutectic solvents, supercritical fluid extraction, microwave-assisted extraction, column chromatography, and high-performance thin-layer chromatography. Transitioning into pharmacological implications, the study unveils quercetin's roles in anti-inflammatory pathways, antioxidant effects, and immune modulation, reflecting its versatile significance in health management. The review highlights its impact on wound healing processes and its potential to mitigate arthritis, elucidating its holistic contributions. Culminating in an exploration of recent studies, the analysis underscores quercetin's remarkable anti-inflammatory and anti-arthritis activities, reflecting its substantial potential across various ailments. The review concludes by projecting future trajectories, emphasizing prospects for an advanced understanding of quercetin's mechanisms, sustainable extraction techniques, clinical integration, and exploration of synergistic combinations. Collectively, this review investigation underscores quercetin's dynamic role at the intersection of natural compounds and medicinal applications, offering profound implications for well- being and health enhancement.

Important carotenoids derived from marine biomass: Extraction, stabilization, and potentiality in food, cosmetics, and pharmaceutical application

Marine organisms are an important source of bioactive compounds, among which marine carotenoids have garnered attention for their health benefits. Hundreds of carotenoids are extracted from different natural biomass; among them marine carotenoids always have special appeal due to their unique properties. This review discusses recent literature on marine carotenoids, extraction and stabilization methods, and their applications in various industries. Green extraction techniques that use supercritical carbon dioxide (SC–CO2) and natural deep eutectic solvents were highlighted in addition to conventional extraction solvents. As most natural carotenoids are highly unstable, this review describes recent advances to stabilize these bioactive compounds. This work offers new insights into marine carotenoids and their potential application in the food, pharmaceutical, and cosmetic industries.

Natural deep eutectic solvents pretreatments for sludge dewaterability improvement and subsequent volatile fatty acids production: Insights of sludge disintegration and metagenomic characterization

Higher economic returns and carbon–neutral benefits drive research shifting to volatile fatty acids (VFAs) recovery from sludge treatment. The novel natural deep eutectic solvents (NADES) based pretreatments of waste activated sludge (WAS) were proposed, focusing on sludge dewaterability, organics dissolution, and subsequent production of VFAs via anaerobic fermentation. Three different pretreatment methods, i.e., NADES treatment alone, NADES with 80 °C thermal treatment, and NADES with 180 °C hydrothermal treatment were systematically compared. The dewaterability of sludge significantly improved only when NADES assisted by thermal treatments, which was interpreted by a substantial decline in capillary suction time (CST) and water-holding capacity. All three pretreatments boosted the VFAs production from sludge (1.40–2.33 times compared with control), and increased the proportion of acetic acid by about 10%. Results showed that the highest VFAs yield of 2728.71 mg COD/L was obtained from NADES combined with 180 °C hydrothermal treatment, which was increased by 133 % compared with the control. Such performance is much higher than a surfactant assisted hydrothermal treatment recently reported in the literature (increased by 27 %). Mechanistic studies elucidated that NADES stimulated sludge solubilization, enhancing the release of organic substrates for VFAs production. Further metagenomic analysis demonstrated that the hydrolytic-acidogenic bacteria were enriched after NADES treatments. Moreover, glycosyl transferases (GTs) and carbohydrate esterases (CEs) were the primary carbohydrate-active enzymes (CAZymes) enhanced by NADES addition. This study provides new insights into green solvents simultaneously enhanced sludge dewatering and resource recovery.

Advanced NADES-based extraction processes for the recovery of phenolic compounds from Hass avocado residues: A sustainable valorization strategy

Natural Deep Eutectic Solvents (NADES) are eco-friendly solvents with considerable potential for extracting bioactive compounds. In this study, we aimed to extract phenolic compounds from Hass avocado residues (epicarp and seed) using NADES in combination with ultrasound-assisted extraction (UAE) and pressurized liquid extraction (PLE) as advanced processes. Ten eutectic mixtures, consisting of choline chloride (ChCl) or betaine as hydrogen bond acceptors (HBA), as well as fructose (Fru), glucose, lactic acid (Lac), citric acid, or glycerol as hydrogen bond donors (HBD), were prepared through stirring and heating. The estimated values for total phenol content (TPC), proanthocyanidin content (PAC), monomeric anthocyanin content (MAC), and antioxidant capacity of the extracts demonstrated a noticeable influence of these solvents. The PLE process significantly enhanced the extraction of phenolic compounds from the epicarp, as evidenced by TPC (185 ± 9 mg gallic acid equivalent/g dry sample) and PAC (77.8 ± 6 mg proanthocyanidin B2/g dry sample) values. Phytochemical characterization conducted via HPLC-QTOF-MS/MS revealed the great extraction capacity of ChCl:Fru and ChCl:Lac, and the improvement of extraction efficiency through PLE. The results suggest that employing these innovative solvents along with advanced extraction processes, especially under high pressures, provides a sustainable approach to recover extracts with high content of phenolic compounds from Hass avocado agro-industrial waste, thus enabling their valorization.

Ultrasound-assisted extraction of sulfonamides from soil samples using natural deep eutectic solvents and their determination by liquid chromatography tandem mass spectrometry

In this work, several potential natural deep eutectic solvents (NADES) were evaluated as sustainable solvents in the development of an ultrasound (US)-assisted extraction method for sulfonamides from soil samples and final determination by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Choline chloride (ChCl) was used as hydrogen bond acceptor (HBA), and different carboxylic acids and alcohols were tested as hydrogen bond donors (HBDs) in different molar ratios in order to find the optimum combination able to form appropriated NADES for the extraction of sulfonamides. Among the different mixtures tested, the one consisting of ChCl:1,3-propanediol in a molar ratio of 1:4 showed the better physico-chemical properties and was selected for the US-assisted extraction of sulfonamides. Under optimum conditions, no matrix effect was observed and quantitative recoveries, ranging from 81.9 % to 103.9 % with relative standard deviations (RSDs) lower than 8 % were obtained, reaching limits of quantification within the range 8.5–31 µg Kg−1, depending upon the analyte. In addition, after evaluation by AGREEprep, Sample Preparation Metric of Sustainability (SPMS) and Blue Applicability Grade Index (BAGI) metrics tools, the proposed method was found to be superior to other published methods in terms of safety and environmental impact with good applicability potential.

Solvent Bar Microextraction Method Based on a Natural Deep Eutectic Solvent and Multivariate Optimization for Determination of Steroid Hormones in Urine and Water

Steroid hormones may pose potential risks to both human health and wildlife, primarily through the consumption of medication or polluted food and water; efforts are being made to monitor their levels in the human body and regulate and minimize their releases to the environment. In this study, a simple and environmentally friendly sample preparation method was developed to simultaneously determine three steroid hormones in urine and water samples. A monoterpene (menthol) and a fatty acid (lauric acid) were combined in various ratios to form a hydrophobic deep eutectic (HDE) solvent as an extraction solvent in solvent bar microextraction (SBME). Using a univariate strategy, a menthol-to-lauric acid HDE ratio of 4:1 and a pH 7 of the sample solution resulted in the highest extraction efficiency (EE%) of the selected steroids. The computational methods have been employed to predict a 4:1 HDE interaction with chosen steroids. Additionally, chemometric approaches suggested that the optimal extraction conditions involved HDEs as extract solvent confined within three SBME devices directly immersed into a 20 mL sample solution with a 30 min extraction time, followed by ultrasonication within 200 μL of elution solvent for a 5 min elution time. Under optimized conditions, the method calibration graph for the spiked selected steroids in the water and urine samples showed good linearity with R2 ≥ 0.994 with limits of detection/quantification lower than 0.40/1.35 μg L−1 and repeatability/reproducibility (RSD%, n = 5) lower than 5.09/7.11. The developed method allows a safe, rapid, and reliable analysis of three steroid hormones in human urine and water samples without using toxic volatile organic solvents.

Extraction of phenolic compounds with antioxidant activity from olive pomace using natural deep eutectic solvents: modelling and optimization by response surface methodology

This work explored the use of natural deep eutectic solvents (NADES) for extracting phenolic compounds with antioxidant activity from Uruguayan olive pomace (OP), a by-product of olive oil mills. Among nine NADES tested, lactic acid-glucose (La-Gc) was the most effective solvent for phenolic compound extraction. Further investigation focused on optimizing the extraction process using La-Gc. Response surface methodology was employed to analyze the impact of extraction temperature, water content in NADES and solid–liquid ratio on total phenols content (TPC) and antioxidant activity (FRAP and DPPH assays). Temperature and solid–liquid ratio greatly influenced TPC and antioxidant activity, while water content in NADES only showed significant influence on antioxidant activity. The optimum extraction conditions that maximized TPC and antioxidant activity were 80 ∘C\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${}^{\\circ }\ ext {C}$$\\end{document}, 68% (w/w) of water in NADES and solid–liquid ratio of 0.014 g/mL, showing a TPC of 15.56 mg GAE/g db, FRAP of 178.14 μ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\mu$$\\end{document}mol FSE/g db and DPPH of 72.75 μ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\mu$$\\end{document}mol TRE/g db, with hydroxytyrosol content of 1.24 mg/g db. These values were significantly higher than those of extracts obtained from conventional solvents under identical extraction conditions. These results highlight the suitability of the present extraction method using La-Gc as solvent to obtain phenolic compounds with antioxidant activity from OP.

Green Extraction of Polyphenols from Elaeagnus angustifolia L. Using Natural Deep Eutectic Solvents and Evaluation of Bioactivity.

In the study, natural deep eutectic solvents (NADESs) were used as alternatives to traditional chemical solvents for the extraction of polyphenols from Elaeagnus angustifolia L. Nine NADESs were tested for the first time and compared with ethanol and water (traditional solvents) regarding the extraction of phenolic compounds from E. angustifolia L. These solvents were particularly effective at extracting polyphenols, whose low water solubility usually requires high amounts of organic solvents. The solvent based on choline chloride and malonic acid provided optimal results and was selected for further optimization. The effects of material-to-liquid ratio, ultrasound time, and ultrasound temperature on the extraction efficiency were studied through single-factor experiments. These parameters were optimized by Box-Behnken design using response surface methodology. The optimal conditions identified were 49.86 g/mL of material-to-liquid ratio, 31.10 min of ultrasound time, and 62.35 °C of ultrasound temperature, resulting in a high yield of 140.30 ± 0.19 mg/g. The results indicated that the NADES extraction technique provided a higher yield than the conventional extraction process. The antioxidant activity of the extract of polyphenols from E. angustifolia L. was determined, and UPLC-IMS-QTOF-MS was used to analyze the phenolic compounds in it. The results revealed that the scavenging ability of 1,1-diphenyl-2-picryl-hydrazil and 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate) extracted by NADES was higher than that of polyphenols extracted by water and ethanol. Furthermore, a total of 24 phenolic compounds were identified in the extract. To the best of our knowledge, this is the first study in which a green and efficient NADES extraction method has been used to extract bioactive polyphenols from E. angustifolia L., which could provide potential value in pharmaceuticals, cosmetics, and food additives.

NADES-based extraction optimization and enrichment of Cyanidin-3-O-galactoside from Rhododendron arboreum Sm.: Kinetics and thermodynamics insights

Cyanidin-3-O-galactoside (Cy3-gal) is the most widespread anthocyanin that has been found to be applicable to nutraceutical and pharmaceutical ingredients. Nevertheless, the process of separation and purification, susceptibilities to heat, and pH inactivation present some limitations. In the present study, natural deep eutectic solvents (NADES) with an ultrasonic-assisted extraction method were briefly studied, and the recovery of Cy3-gal from Rhododendron arboreum was highlighted. The NADES, consisting of choline chloride and oxalic acid (1:1), was screened out as an extractant, and single-factor experiments combined with a two-site kinetic model were employed to describe the extraction process. Further, the work investigated ultrasound-assisted adsorption/desorption to efficiently purify Cy3-gal using macroporous resins. The optimal extraction conditions to attain maximum Cy3-gal yield was 30% water in a 50:1 (mL/g) solvent-to-sample ratio, 11.25 W/cm3 acoustic density, and 50% duty cycle for 16 min of extraction time. Under these conditions, the results revealed 23.07 ± 0.14 mg/g of Cy3-gal, two-fold higher than the traditional solvents. Furthermore, of the different resins used, Amberlite XAD-7HP showed significantly (p < 0.05) higher adsorption/desorption capacities (12.82 ± 0.18 mg/g and 10.97 ± 0.173 mg/g) and recovery (48.41 ± 0.76%) percent over other adsorbents. Experiments on the degrading behavior (40–80 °C) of the recovered Cy3-gal were performed over time, and the first-order kinetic model better explained the obtained data. In conclusion, the study asserts the use of ultrasonication with NADES and XAD-7HP resin for the improved purification of Cy3-gal from the crude extract.

Ultrasound-Assisted Extraction of Phenolic Compounds from Celtuce (Lactuca sativa var. augustana) Leaves Using Natural Deep Eutectic Solvents (NADES): Process Optimization and Extraction Mechanism Research.

Natural deep eutectic solvents (NADESs), as emerging green solvents, can efficiently extract natural products from natural resources. However, studies on the extraction of phenolic compounds from celtuce (Lactuca sativa var. augustana) leaves (CLs) by NADESs are still lacking. This study screened the NADES L-proline-lactic acid (Pr-LA), combined it with ultrasound-assisted extraction (UAE) to extract phenolic compounds from CLs, and conducted a comparative study on the extraction effect with traditional extraction solvents. Both SEM and FT-IR confirmed that Pr-LA can enhance the degree of fragmentation of cell structures and improve the extraction rate of phenolic compounds. Molecular dynamics simulation results show that Pr-LA can improve the solubility of phenolic compounds and has stronger hydrogen bonds and van der Waals interactions with phenolic compounds. Single-factor and Box-Behnken experiments optimized the process parameters for the extraction of phenolic compounds from CLs. The second-order kinetic model describes the extraction process of phenolic compounds from CLs under optimal process parameters and provides theoretical guidance for actual industrial production. This study not only provides an efficient and green method for extracting phenolic compounds from CLs but also clarifies the mechanism of improved extraction efficiency, which provides a basis for research on the NADES extraction mechanism.