UPLC-Triple-TOF/MS characterization of phenolic constituents and the influence of natural deep eutectic solvents on extraction of Carya cathayensis Sarg. peels: Composition, extraction mechanism and in vitro biological activities

Advancing green extraction of bioactive compounds using deep eutectic solvent-based ultrasound-assisted matrix solid-phase dispersion: Application to UHPLC-PAD analysis of alkaloids and organic acids in Coptidis rhizoma

The utilization of deep eutectic solvents (DES) in sustainable extracting and separating of phytochemicals shows promising prospect. An exceptionally fast, eco-friendly, and sustainable approach was proposed for extracting bioactive compounds from Coptidis Rhizoma based on deep eutectic solvent-based ultrasound-assisted matrix solid phase dispersion (DES-UA-MSPD). Single-factor experiments and Box-Behnken design were utilized to explore the optimal extraction conditions. The analysis indicated that the acidic DES, especially betaine-acrylic acid (Bet-Aa 1:4 mol/mol) with 50% water content, was proved to be the most effective medium for the extraction of alkaloids (magnoflorine, groenlandicine, coptisine, epiberberine, berberine and palmatine) and organic acid (chlorogenic acid). With the parameters optimized, the total maximum extraction yield of alkaloids and organic acids reached 128.83 mg g-1 applying the optimal DES, which was 1.33-5.33 folds higher than conventional extraction solvents. Additionally, through microstructure analysis using scanning electron microscopy, density functional theory , and frontier molecular orbitals theory, a deeper understanding of the extraction principle was gained, and the molecular mechanism of DES synthesis and the interactions between target compounds were systematically elucidated. The sustainable and green potential of the DES-UA-MSPD method was demonstrated through Green Analytical Procedure Indexanalysis. The overall results of this investigation revealed that the proposed technology was a highly promising and sustainable alternative for effective extraction and quantification of natural products.

Improving the Composition and Bioactivity of Cocoa (Theobroma cacao L.) Bean Shell Extract by Choline Chloride-Lactic Acid Natural Deep Eutectic Solvent Extraction Assisted by Pulsed Electric Field Pre-Treatment

An environmentally friendly method for the release of cocoa bean shell (CBS) extracts is proposed in this paper. This work aims to investigate the effect of pulsed electric field (PEF) pre-treatment on subsequent solid-liquid extraction (SLE) of metabolites with choline chloride-lactic acid natural deep eutectic solvent (NaDES) and bioactivity of cocoa bean shell (CBS) extract. Two different media for PEF application were evaluated: water and chlorine chloride-lactic acid. Total polyphenols (TPC), total flavonoids (TFC), individual major compounds, and antioxidant and antibacterial activity of CBS extracts were assessed. The performance of PEF-assisted extraction was compared with SLE and ultrasound-assisted extraction (UAE). The proposed method improved the release of TPC up to 45% and TFC up to 48% compared with the conventional extraction. The CBS extract showed medium growth inhibition of Escherichia coli and high growth inhibition of Salmonella sp, Listeria monocytogenes, and Staphylococcus aureus. Thus, an extract with enhanced antioxidant and antibacterial properties was obtained.

Green and Efficient Extraction of Phenolic Components from Plants with Supramolecular Solvents: Experimental and Theoretical Studies

The supramolecular solvent (SUPRAS) has garnered significant attention as an innovative, efficient, and environmentally friendly solvent for the effective extraction and separation of bioactive compounds from natural resources. However, research on the use of a SUPRAS for the extraction of phenolic compounds from plants, which are highly valued in food products due to their exceptional antioxidant properties, remains scarce. The present study developed a green, ultra-sound-assisted SUPRAS method for the simultaneous determination of three phenolic acids in Prunella vulgaris using high-performance liquid chromatography (HPLC). The experimental parameters were meticulously optimized. The efficiency and antioxidant properties of the phenolic compounds obtained using different extraction methods were also compared. Under optimal conditions, the extraction efficiency of the SUPRAS, prepared with octanoic acid reverse micelles dispersed in ethanol-water, significantly exceeded that of conventional organic solvents. Moreover, the SUPRAS method demonstrated greater antioxidant capacity. Confocal laser scanning microscopy (CLSM) images revealed the spherical droplet structure of the SUPRAS, characterized by a well-defined circular fluorescence position, which coincided with the position of the phenolic acids. The phenolic acids were encapsulated within the SUPRAS droplets, indicating their efficient extraction capacity. Furthermore, molecular dynamics simulations combined with CLSM supported the proposed method's mechanism and theoretically demonstrated the superior extraction performance of the SUPRAS. In contrast to conventional methods, the higher extraction efficiency of the SUPRAS can be attributed to the larger solvent contact surface area, the formation of more types of hydrogen bonds between the extractants and the supramolecular solvents, and stronger, more stable interaction forces. The results of the theoretical studies corroborate the experimental outcomes.

Extracting bioactive compounds and proteins from Bacopa monnieri using natural deep eutectic solvents

This study employed novel extraction methods with natural deep eutectic solvents (NADES) to extract bioactive compounds and proteins from Bacopa monnieri leaves. The conditional influence of ultrasonic-assisted extraction (UAE), microwave-assisted extraction (MAE), and enzymatic-assisted extraction (EAE) on the recovery efficiency of phenolics, proteins, flavonoids, and terpenoids was evaluated. The conditions of UAE were 50 mL/g LSR, 600W of ultrasonic power, and 30% water content with 40°C for 1 min to obtain the highest bioactive compounds and protein contents. The conditions of MAE were 40 mL/g LSR, 400W of microwave power with 30% water content for 3 min to reach the highest contents of biological compounds. The conditions of EAE were 30 mL/g of LSR, 20 U/g of enzyme concentration with L-Gly-Na molar ratio at 2:4:1, and 40% water content for 60 min to acquire the highest bioactive compound contents. Scanning electron microscopy (SEM) is employed to analyze the surface of Bacopa monnieri leaves before and after extraction. Comparing seven extraction methods was conducted to find the most favorable ones. The result showed that the UMEAE method was the most effective way to exploit the compounds. The study suggested that UMEAE effectively extracts phenolics, flavonoids, terpenoids, and protein from DBMP.

Phenolic diversity and antioxidant potential of different varieties of bamboo leaves using LC-ESI-QTOF-MS/MS and LC-ESI-QqQ-MS/MS

Bamboo is a highly sustainable plant with a wide variety of leaves, yet little is known about its bioactive composition. Therefore, this study aims to characterize the phenolic profile and antioxidant capacity of 11 different varieties of bamboo leaves using liquid chromatography coupled with mass spectrometry. As a result, 81 phenolic compounds were tentatively identified, 29 of which were identified for the first time in the literature for bamboo leaves. The tentatively identified compounds fell into five classes (hydroxybenzoic and hydroxycinnamic acids, flavones, flavanones, and flavonols). The concentration of phenolic compounds ranged from 103 to 1291 mg/100 g. Among the provisionally identified compounds, there was a predominance of derivatives from the luteolin and apigenin group, with orientin and schaftoside being the majority in each group, respectively. The leaves also showed significant variation in antioxidant activity, highlighting the potential bioactive composition of bamboo leaves for future applications in the food industry.

A Sustainable Extraction Approach of Phytochemicals from Date (Phoenix dactylifera L.) Fruit Cultivars Using Ultrasound-Assisted Deep Eutectic Solvent: A Comprehensive Study on Bioactivity and Phenolic Variability

The present study aimed to evaluate the efficacy of natural deep eutectic solvents (NADESs) on the extraction of phytochemicals from eight Algerian date fruit cultivars (Phoenix dactylifera L.). In this study, lactic acid/sucrose-based NADESs were used as an alternative to conventional chemical solvents using the ultrasound-assisted extraction (UAE) method. The obtained extracts were assessed for the determination of bioactive compound contents, phenolic composition, antioxidant activity, and enzyme inhibitory potential. The results showed a considerable variation in phytochemical compositions and related activities between cultivars, where the greatest contents of total phenolics (1288.7 mg GAE/100 g), total flavonoids (53.8 mg QE/100 g), proanthocyanidins (179.5 mg CE/g), and total triterpenoids (12.88 mg OAE/100 g) were detected in the fruits of the Ourous cultivar. The same cultivar displayed the highest antioxidant capacity against DPPH• free radical (595 mg AAE/100 g), ABTS•+ cation radical (839 mg TE/100 g), and ferric reducing antioxidant potential (704 mg AAE/100 g). All extracts manifested moderate antioxidant activities tested by phosphomolybdenum, NO•, and linoleic acid lipid peroxidation assays. These extracts also exhibited interesting levels of in vitro enzyme inhibition; the Ourous cultivar gave the best inhibitory activity against α-amylase and acetylcholinesterase with 45 and 37%, respectively. HPLC-DAD-MS detected a total of five compounds, with phenolic acids and flavonoids being the main phenolics identified in the extract. The phenolic composition exhibited significant variability among cultivars. Notably, the highest amounts were revealed in the Tazizaout cultivar, with the predominance of gallic acid. The results confirmed that the combination of UAE and NADESs provides a novel and important alternative to chemical solvents for sustainable and environmentally friendly extraction and can represent a good alternative in food and pharmaceutical industry applications.

Eco-friendly and efficient extraction of polyphenols from Ligustrum robustum by deep eutectic solvent assisted ultrasound

An eco-friendly and efficient extraction method using deep eutectic solvents assisted ultrasound extraction (DESs-UAE) for the polyphenols from Ligustrum robustum was developed. Among the 34 kinds of DESs prepared, tetraethyl ammonium bromide: 1,2,4-butanol (Teab: 1,2,4-But) was proved to be a suitable extraction solvent based on the extraction efficiency. The extraction parameters including temperature, water content, liquid-solid ratio were optimized with response surface methodology (RSM). Under the optimal conditions, the total phenolic content (TPC) and total flavonoid content (TFC) were 101.46 ± 2.96 mg GAE/g DW and 264.17 ± 5.39 mg RE/g DW, respectively. Furthermore, the extraction mechanism of DESs-UAE was investigated by extraction kinetics, molecular dynamic simulation and theory calculations of interaction. In particular, 9 kinds of polyphenols compounds from Ligustrum robustum were firstly identified by UPLC-Q-TOF-MS. Moreover, the recovered polyphenols exhibited significant antioxidant, α-glucosidase inhibition, acetylcholinesterase inhibition and anticancer activity.

Screening and Characterization of an α-Amylase Inhibitor from Carya cathayensis Sarg. Peel

Inhibiting α-amylase can lower postprandial blood glucose levels and delay glucose absorption, offering an effective approach for the development of antidiabetic diets. In this study, an active constituent with inhibitory activity against α-amylase was isolated and purified by bioassay-guided fractionation from Carya cathayensis Sarg. peel (CCSP). The active constituent was identified by NMR and Q-Exactive Orbitrap Mass Spectrometry as 5-O-p-coumaroylquinic acid (5-CQA). 5-CQA possessed strong inhibitory activity against α-amylase, with an IC50 value of 69.39 µM. In addition, the results of the kinetic study indicated that 5-CQA was a potent, reversible, noncompetitive inhibitor against α-amylase. The findings indicate that 5-CQA derived from CCSP has potential as a novel inhibitor against α-amylase, which can help mitigate postprandial blood sugar spikes, making it suitable for inclusion in antidiabetic diets.

Natural deep eutectic ready to use extract of astilbin: Super high in vitro bioaccessibility, α-amylase and α-glucosidase enzyme inhibition kinetics

Astilbin, a natural flavonoid, possesses multiple functionalities, while the poor bioavailability seriously restricts its application in functional food and medicine. Therefore, in this study, a natural deep eutectic solvent (NaDES) with choline chloride: lactic acid (CHCL-LAC) is selected to deliver astilbin by evaluating the bioaccessibility and antioxidant capacity during in vitro gastrointestinal digestion, and the inhibitory effect with underlying mechanism of astilbin-CHCL-LAC against α-amylase/α-glucosidase were investigated. The CHCL-LAC showed significant high astilbin bioaccessibility (84.1% bioaccessible) and DPPH and ORAC antioxidant capacity with 75.7% and 57.7% respectively after 3 h in vitro digestion, which may be attributed by hydrogen bond based supramolecule formed between astilbin and CHCL-LAC. Moreover, significant inhibitions of astilbin-CHCL-LAC on α-amylase (IC50 of 0.67 g/L) and α-glucosidase (IC50 of 0.64 g/L) were observed in mixed competitive and non-competitive manners. The dominant binding force between enzymes and astilbin were the hydrogen and hydrophobic interaction. This is the first time that the underlying mechanisms for astilbin delivered by NaDESs were revealed, suggesting that CHCL-LAC-based NaDESs are promising ready-to-use vehicles of natural inhibitors for carbohydrate-hydrolyzing enzymes.

Green Extraction of Polyphenols via Deep Eutectic Solvents and Assisted Technologies from Agri-Food By-Products

Polyphenols are the largest group of phytochemicals with important biological properties. Their presence in conveniently available low-cost sources, such as agri-food by-products, has gained considerable attention in their recovery and further exploitation. Retrieving polyphenols in a green and sustainable way is crucial. Recently, deep eutectic solvents (DESs) have been identified as a safe and environmentally benign medium capable of extracting polyphenols efficiently. This review encompasses the current knowledge and applications of DESs and assisted technologies to extract polyphenols from agri-food by-products. Particular attention has been paid to fundamental mechanisms and potential applications in the food, cosmetic, and pharmaceutical industries. In this way, DESs and DESs-assisted with advanced techniques offer promising opportunities to recover polyphenols from agri-food by-products efficiently, contributing to a circular and sustainable economy.

Ultrasound-Assisted Extraction of Taro Leaf Antioxidants Using Natural Deep Eutectic Solvents: An Eco-Friendly Strategy for the Valorization of Crop Residues

Colocasia esculenta L. leaves are considered a by-product of taro cultivation and are discarded as environmental waste, despite their valuable phenolic composition. Their valorization to obtain value-added substances for medicinal, food, and cosmetic applications is the aim of the current work. An ultrasound-assisted extraction was developed for the environmentally friendly and sustainable isolation of taro leaf antioxidants using natural deep eutectic solvents (NaDESs). Among the utilized solvents, the NaDES based on betaine and ethylene glycol provided the best extraction efficiencies in terms of polyphenolic content and antioxidant activity. Multi-response optimization suggested a solvent-to-solid ratio of 10 mL g-1, a processing time of 60 min, an extraction temperature of 60 °C, and a water content of 33.8% (w/w) as optimal extraction parameters. Leaf extract obtained under these optimum operational parameters demonstrated a strong radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (65.80 ± 0.87%), a high ferric reducing antioxidant power (126.62 ± 1.92 μmol TE g-1 sample), and significant protection against oxidative stress-induced DNA damage. The chromatographic characterization of the optimum extract revealed its richness in flavonoids (flavones and flavonols). The outcomes of the present study suggest that the proposed method could serve as a highly efficient and green alternative for the recovery of polyphenols from agricultural wastes.

Total biflavonoids extraction from Selaginella chaetoloma utilizing ultrasound-assisted deep eutectic solvent: Optimization of conditions, extraction mechanism, and biological activity in vitro

In this study, the deep eutectic solvent based ultrasound-assisted extraction (DES-UAE) was investigated for the efficient and environmentally friendly extraction of Selaginella chaetoloma total biflavonoids (SCTB). As an extractant for optimization, tetrapropylaminium bromide-1,4-butanediol (Tpr-But) was employed for the first time. 36 DESs were created, with Tpr-But producing the most effective results. Based on response surface methodology (RSM), the greatest extraction rate of SCTB was determined to be 21.68 ± 0.78 mg/g, the molar ratio of HBD to HBA was 3.70:1, the extraction temperature was 57 °C, and the water content of DES was 22 %. In accordance with Fick's second rule, a kinetic model for the extraction of SCTB by DES-UAE has been derived. With correlation coefficients 0.91, the kinetic model of the extraction process was significantly correlated with the general and exponential equations of kinetics, and some important kinetic parameters such as rate constants, energy of activation and raffinate rate were determined. In addition, molecular dynamics simulations were used to study the extraction mechanisms generated by different solvents. Comparing the effect of several extraction methods on S.chaetoloma using ultrasound-assisted extraction and conventional methods, together with SEM examination, revealed that DES-UAE not only saved time but also enhanced SCTB extraction rate by 1.5-3 folds. SCTB demonstrated superior antioxidant activity in three studies in vitro. Furthermore, the extract could suppress the growth of A549, HCT-116, HepG2, and HT-29 cancer cells. Alpha-Glucosidase (AG) inhibition experiment and molecular docking studies suggested that SCTB exhibited strong inhibitory activity against AG and potential hypoglycemic effects. The results of this study indicated that a Tpr-But-based UAE method was suitable for the efficient and environmentally friendly extraction of SCTB, and also shed light on the mechanisms responsible for the increased extraction efficiency, which could aid in the application of S.chaetoloma and provide insight into the extraction mechanism of DES.

Synthesis and characterization of fucoidan/chitosan-coated nanoliposomes for enhanced stability and oral bioavailability of hydrophilic catechin and hydrophobic juglone

This study aimed to improve the thermodynamic performance of nanoliposomes (NLs) using fucoidan (F) as the second-layer coating biopolymer along with chitosan (CS), to control the delivery and bioavailability of catechin (C) and juglone (J). The stabilized liposomal carrier of F/CS-conjugated JC-NL (F-CS-JC-NL) was developed with optimum concentrations of CS (0.09 wt%) and F (0.10 wt%), with the highest encapsulation efficiency of juglone (95.47%) and catechin (90.88%). Physicochemical characterization revealed that F-CS-JC-NL disclosed improved stability under different pH and ionic strengths, with the maximum juglone/catechin retention under thermal, oxidative and storage conditions. In vitro digestion revealed that NL double-coating (F-CS-JC-NL) significantly reduced compound leakage in the gastrointestinal tract, providing a controlled release and better bioavailability of juglone/catechin compared to CS-JC-NL and JC-NL. Conclusively, this study provides a novel NL-based delivery carrier with enhanced physicochemical stability and controlled release that might have promising use in delivering functional ingredients.

Green extraction of total phenolic and flavonoid contents from mangosteen (Garcinia mangostana L) rind using natural deep eutectic solvents

This research combined ultrasonic-assisted extraction (UAE) and natural deep eutectic solvent (NADES) to recover phenolic and flavonoid components from mangosteen rind. The antioxidant activities were determined using DPPH, ABTS⁺, and hydroxyl assays. NADES prepared from lactic and 1,2-propanediol had the highest extraction efficiency based on the total flavonoid content (TFC) and phenolic contents (TPC). Single-factor experiments were employed to assess the influence of UAE conditions (liquid-to-solid ratio, temperature, water content in NADES, and time) on TFC, TPC, and antioxidant activities. NADES-based UAE conditions were optimized using response surface methodology with the Box-Behnken design model on five dependent responses (TPC, TFC, DPPH, ABTS, and OH). The optimal conditions for the lactic-1,2-Propanediol-based UAE process were 76.7 ml liquid/g solid with 30.3% of water content at 57.5 °C for 9.1 min. Scanning electron microscopy (SEM) was applied to examine the surface morphology of mangosteen rind before and after sonication. This study proposes an efficient, green, and practical approach for recovering phenolics and flavonoids from mangosteen rinds.

UPLC-MS/MS profiling, antioxidant and anti-inflammatory activities, and potential health benefits prediction of phenolic compounds in hazel leaf

Hazel leaf, one of the by-products of hazelnut, which is widely used in traditional folk medicine around the world. In the present study, the profile of free, conjugated, and bound phenolic compounds from hazel leaf was detected and their antioxidant and anti-inflammatory activities were investigated. The potential health benefits of different phenolic compounds were also predicted. The results showed that the 35 phenolic substances of free, conjugated and bound forms were identified including phenolic acids, flavonoids and catechins. Most of the hazel leaf phenolics were presented in free form, followed by conjugated and bound form. All the fractions effectively inhibited the production of reactive oxygen species and malondialdehyde in TBHP-stimulated human umbilical vein endothelial cells by enhancing endogenous superoxide dismutase, and accordingly alleviated inflammatory cytokines (NO, IL-1β, TNF-α, and IL-6) in LPS-stimulated RAW264.7 cells, showing obvious antioxidant and anti-inflammatory capacity. Moreover, combined with network pharmacology, the potential therapeutic effects and functional pathways of hazel leaf phenolics were predicted, which provided value basis for exploring their treatment on diseases and developing health products in the future.

Current advances on the therapeutic potential of pinocembrin: An updated review

Pinocembrin (5,7-dihydroxyflavone) is a major flavonoid found in many plants, fungi and hive products, mainly honey and propolis. Several in vitro and preclinical studies revealed numerous pharmacological activities of pinocembrin including antioxidant, anti-inflammatory, antimicrobial, neuroprotective, cardioprotective and anticancer activities. Here, we comprehensively review and critically analyze the studies carried out on pinocembrin. We also discuss its potential mechanisms of action, bioavailability, toxicity, and clinical investigations. The wide therapeutic window of pinocembrin makes it a promising drug candidate for many clinical applications. We recommend some future perspectives to improve its pharmacokinetic and pharmacodynamic properties for better delivery that may also lead to new therapeutic advances.

Preparation process optimization and evaluation of bioactive peptides from Carya cathayensis Sarg meal

Carya cathayensis Sarg meal (CM) is a by-product of the edible kernel during oil manufacture. In order to improve wastes utilization, the CM derived peptides (CMPs) that showed an in vitro radical scavenging ability were firstly prepared by five different hydrolases. Alcalase treatment revealed the highest yield and the optimal conditions were further determined by response surface methodology (RSM), under which the yield reached 35.84%. Simulated gastrointestinal digestion led to an enrichment of low molecular weight (MW) peptides (<3 kDa), which was beneficial for protecting hepatocyte damaged by hydrogen peroxide (H₂O₂). Furthermore, generated hydrolysates exhibited protective effects on paraquat-induced Caenorhabditis elegans via enhancing expressions of Skinhead-1 (SKN-1) and its downstream target including glutathione S-transferase (GST)-4 and superoxide dismutase (SOD)-3 to diminish oxidative stress. Taken together, our results demonstrated that simple enzymatic hydrolysis of crude protein powder from CM represents an efficient, eco-friendly and economical strategy for producing bioactive peptides, which can be supplemented in nutraceutical products and food preservation.

Green extraction, chemical composition, and in vitro antioxidant activity of theabrownins from Kangzhuan dark tea

Theabrownins (TBs) in dark tea have received increasing attention for their multiple health benefits. In this study, ultrasound assisted extraction with deep eutectic solvent (UAE-DES) was developed for the extraction of TBs from Kangzhuan dark tea (KZDT). The highest yield (12.59%) of TBs was obtained using UAE-choline (ChCl)/malic acid (MA) with a liquid to solid ratio of 20:1 (v/w), ultrasonic power of 577 W, ultrasonic time of 25 min, and water content of 30%. TBs were further eluded by silica gel to obtain six theabrownine fractions (TBFs), namely, TBFs1, TBFs2, TBFs3, TBFs4, TBFs5, and TBFs6. LC-MS/MS revealed that flavonoids, terpenes, phenolic acids, alkaloids, lipids, and amino acids are the leading components of TBFs. The TBFs4, with the DPPH, ABTS, and FRAP values of 45.08 ± 0.42 μM Ascorbic acid/g DW, 178.52 ± 0.29 μM Trolox/g DW, and 370.85 ± 6.00 μM Fe(II)/g DW, respectively, showed the highest antioxidant activity among all the TBFs. Overall, this study first provided the evidence that UAE-ChCl/MA combining with silica gel was effective to extract TBs from KZDT, and the 6,7-dihydroxycoumarin-6-glucoside and neohesperidin were found as the leading compounds in the TBFs, providing a guidance for the chemical research and further utilization of dark tea and its TBs.

•

Yield of TBs of 12.59% from KZDT was achieved by UAE-ChCl/MA.

•

Silica gel powder with methanol (100%–0%) as a mobile phase was used for TBs separation.

•

The chemical component of TBFs was revealed.

•

Flavonoids are among the leading compounds in the TBFs.

•

TBFs4 displayed the highest in vitro antioxidant activity.

Acidified glycerol as a one-step efficient green extraction and preservation strategy for anthocyanin from blueberry pomace: New insights into extraction and stability protection mechanism with molecular dynamic simulation

In present work, green and efficient glycerol solvent system was coupled with pulse-probe ultrasonication for one-step extraction and preservation of anthocyanin from blueberry pomace. Under optimal conditions (40 min, 174 W, 18.6 mL/g, 20% of glycerol fraction), extraction yield was 23.07 ± 0.09 mg C3GE/g DW. The extracted anthocyanins were characterized by UPLC-Triple-TOF/MS and 10 anthocyanins compounds were tentatively identified. Stability of anthocyanins influenced by solvents were evaluated in varying temperature, pH and light exposure conditions, demonstrating higher stability of anthocyanins in glycerol solvent system than methanol one. Furthermore, mechanism of high efficiency extraction and stability of anthocyanin using glycerol were investigated by quantum chemical calculation with molecular dynamic simulation. Larger solvent accessible surface area (127.16 nm²), hydrogen bonds number (228.16) and hydrogen bonds lifetime (4.35 ps), and lower intermolecular interaction energy (-1080.48 kJ/mol) between anthocyanin and glycerol were responsible for better extraction and preservation of anthocyanins using glycerol system.

Development and characterization of chitosan/guar gum active packaging containing walnut green husk extract and its application on fresh-cut apple preservation

The aim of this work was to develop active packaging film by using chitosan/guar gum (CG) film matrix and walnut green husk extract (WE), for preservation of fresh-cut apple. WE was used as cross-linking agent to improve physicochemical properties, and as active substances to enhance antioxidant activity of CG films. Fourier transform infrared spectroscopy and scanning electron microscopy results showed WE formed intermolecular hydrogen bond interactions with the film matrix, and microstructures of the film were more compact. With the increase of WE content (0-4 wt%), the mechanical properties of composite films were significantly enhanced, while permeability of water vapor and oxygen was significantly decreased (p < 0.05). When the amount of extract reached 4 wt%, the DPPH radical scavenging activity of composite film was significantly increased to 94.59%. CG-WE and CG films were used as active packaging materials to preserve fresh-cut apple. When stored at 4 °C for 10 days, CG-WE films showed better performance in reducing firmness, weight loss, total soluble solids and inhibiting browning and microbial growth of fresh-cut apples. Therefore, as a new type of active food packaging material, CG-WE films have good physical properties, and great potential in ensuring food quality and extending shelf life.

Chemical Constituent Analysis of Ranunculus Sceleratus L. Using Ultra-High-Performance Liquid Chromatography Coupled with Quadrupole-Orbitrap High-Resolution Mass Spectrometry

Ranunculus sceleratus L.(RS) has shown various pharmacological effects in traditional Chinese medicine. In our previous study, the positive therapeutic effect on α-naphthylisothiocyanate induced intrahepatic cholestasis in rats was obtained using TianJiu treatment with fresh RS. However, the chemical profile of RS has not been clearly clarified, which impedes the research progress on the therapeutic effect of RS. Herein, an ultra-high performance liquid chromatography coupled with quadrupole Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) method was developed to rapidly separate and identify multiple constituents in the 80% methanol extract of RS. A total of sixty-nine compounds (19 flavonoids, 22 organic acids, 6 coumarins, 4 lignans, 14 nitrogenous compounds, and 4 anthraquinones) were successfully characterized. A total of 12 of these compounds were unambiguously identified by standard samples. Their mass spectrometric fragmentation pathways were investigated. It is worth noting that flavonoids and lignans were identified for the first time in RS. In this study, we successfully provide the first comprehensive report on identifying major chemical constituents in RS by UHPLC-Q-Orbitrap HRMS. The obtained results enrich the RS chemical profile, paving the way for further phytochemical study, quality control, and pharmacological investigation of RS.

Oriented Deep Eutectic Solvents as Efficient Approach for Selective Extraction of Bioactive Saponins from Husks of Xanthoceras sorbifolia Bunge

The husks of Xanthoceras sorbifolia Bunge (X. sorbifolia), as by-products of industrial production, have brought a severe burden to the environment and caused an enormous waste of resources. Bioactive triterpenoid saponins are rich in the husks. To reuse the husks and gain high-quality saponin products, saponin-oriented deep eutectic solvents (DESs), as an efficient and selective extraction strategy from X. sorbifolia husks, were designed for the first time. The enhancement of the extraction rate was investigated by screening solvents from acidic DESs and response surface methodology (RSM) optimization. As a result, the tetrapropylammonium bromide-lactic acid (TPMBr-La) was the most efficient DESs, with an extraction efficiency of up to 135% higher than 70% ethanol. A maximum extraction rate of 72.11 ± 0.61 mg Re/g dw was obtained under the optimized parameters. Scanning electron microscope graphs revealed that damage to the microstructure caused by DESs enhanced the extraction efficiency. Moreover, the recovery of total saponins with D101 macroporous resin was consistent with the pseudo-second-order kinetic model. Seven saponins were also identified by HPLC-MS analysis. Finally, TPMBr-La extracts exhibited 92.30 ± 1.10% DPPH radical scavenging rate at 100 μg/mL, and 92.20 ± 0.30% ABTS radical scavenging rate at 1200 μg/mL. Our current research proposes a selective and high-efficiency substitute for the extraction of saponins and might contribute to further DESs application in the recycling of by-products.

Ultrasound-assisted deep eutectic solvents extraction of glabridin and isoliquiritigenin from Glycyrrhiza glabra: Optimization, extraction mechanism and in vitro bioactivities

Licorice (Glycyrrhiza glabra) is extensively used owing to the superior pharmacological effects. However, its maximum application potential has not been fully exploited due to the limitation of currently available extraction solvent and methods. In this study, an eco-friendly deep eutectic solvent (NADESs) based ultrasound-assisted extraction (DES-UAE) method was applied to prepare licorice extracts. The DES-UAE using choline chloride and lactic acid as solvent was optimized and modeled by using response surface methodology to maximize the extraction yields of glabridin (GLA) and isoliquiritigenin (ISL). The optimized extracts possessed higher contents of GLA and ISL than available extraction methods, and the enriched products showed superior pharmacological activities in vitro. Furthermore, scanning electron microscopy (SEM) and molecular dynamic simulation analyses were performed to deeply investigate the interaction between solvent and targeted compounds. This study not only provides an eco-friendly method for high-efficient extraction of GLA and ISL from licorice but also illustrates the mechanism of the increased extraction efficacy, which may contribute to the application of licorice and deep insight into extraction mechanism using DES.