Solid-liquid Ratio Research Articles

Ultrasound-Cellulase Synergy for the Extraction of Total Flavonoids from Astragali complanati Semen and Its Antioxidant Properties

The present study was conducted to optimize ultrasound-cellulase synergy extraction (UCSE) process of flavonoids from Astragali complanati Semen (ACS) adopting response surface methodology (RSM). The extraction efficiency of different extraction progress by UCSE under the 240W and 480W were compared, and the antioxidant activities were evaluated in vitro. The effects of five independent variables (cellulase addition, liquid-solid ratio, extraction time, extraction temperature, and ultrasonic power) on the extraction efficiency were explored, and four major factors (cellulase addition, liquid-solid ratio, extraction temperature and ultrasonic power) showing great influences were chosen to study their interactions by RSM. The relationships between ultrasound power 240W and 480W on substrates and cellulase were further explored by scanning electron microscopy and 3,5-dinitrosalicylic acid (DNS) method, respectively. The antioxidant activities on 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH) and 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate) radical (ABTS+) were evaluated in vitro. The optimal conditions: cellulase addition 930 U/g, liquid-solid ratio 24mL/g, extraction time 75min, extraction temperature 64°C and ultrasonic power 234W, under the adjusted conditions, the extraction rate was 1.937g/100g ACS. Ultrasound power 240W assisted extraction with cellulase improved the extraction efficiency of the antioxidant. From scanning electron microscopy, the substrate particles were finer and the pores were larger under the function of 240W, and the enzyme activity test further determined that 480W could reduce the effect of the cellulase. The UCSE extract exhibited great antioxidant activity in vitro, the IC50 of DPPH is 11.851µg/mL, and of ABTS+ is 23.426µg/mL.

Preparation and characterization of insoluble β-glucan from waste beer yeast

The management of brewery waste, particularly waste brewer's yeast, has posed a significant environmental and economic challenge. This study proposed an approach to valorize waste brewer's yeast by extracting β-glucan. The key phases of the research included yeast autolysis, alkaline treatment and optimization of the β-glucan purification conditions. The findings revealed that a 0.7 % NaOH concentration at 80 °C for 2.6 h was the most effective for impurity removal. In the comparative analysis, it was confirmed that extraction at 80 % DMSO concentration with a 30:1 solid-liquid ratio at 80 °C for 30 min was the optimal condition for obtaining high-purity β-glucan. The process yielded a β-glucan high purity of 95.84 ± 1.15 % and a yield of 5.56 ± 0.34 % based on the wet weight after centrifugation. The structure was analyzed using TLC, FTIR and NMR. The extracts are polysaccharides composed of glucose monomers linked by β-glycosidic bonds. In addition, It has demonstrated significant anti-inflammatory properties in vitro and can be developed as a functional food. This study provides a feasible and efficient solution for the sustainable utilization of waste brewer's yeast, contributing to environmental sustainability and offering economic benefits for the brewing industry.

Direct CO2 mineralization and evolution behavior of fine CaCO3 from ammonia-induced phosphogypsum mineral carbonation

The mineral carbonation of phosphogypsum (PG) presents considerable potential for simultaneous CO2 sequestration and high-value utilization of PG. Variations in carbon footprints are crucial for enhancing carbonation efficiency and regulating product formation. This study explores the mechanism of direct CO2 mineralization by PG and the evolution of the resulting product. The results demonstrate that 97.14% of the CaSO4·2H2O in PG can be converted to calcite under conditions including a nitrogen–sulfur molar ratio of 3, a liquid–solid ratio of 6, a CO2 flowrate of 0.4 L/min, and a stirring rate of 800 rpm for 60 min. The carbonation rate exhibits significant variation with time, occurring in three distinct stages. Initially, CO2 reacts with ammonia to form (NH4)2CO3, releasing greater heat. This heat inhibits the dissolution of Ca2+ from PG, resulting in a lower carbonation efficiency, as only a limited amount of Ca2+ reacts with CO32– to preferentially form amorphous CaCO3 (ACC). As CO32– formation reaches equilibrium, the endothermic properties of the reaction between CaSO4 and (NH4)2CO3 promote the dissolution of Ca2+ from PG, further accelerating CO2 mineralization and resulting in significant increases in carbonation efficiency and ACC production. The ACC is rapidly transformed into calcite via a “dissolution-reprecipitation” mechanism. However, the carbonation rate of PG decreases as saturation is approached, mainly resulting from the aggregation of fine CaCO3 particles on the PG surface. As a result, the direct CO2 sequestration process by PG follows a carbon footprint sequence of “CO2–(NH4)2CO3–ACC–calcite”. This study provides significant insights into the mechanisms of direct CO2 mineralization and product evolution and offers a basis for optimizing carbonation processes enhancement and regulating product phases.

Extraction of fucoidan and alginate from Sargassum thunbergii using dimethylamine solution: Insights into the process and mechanism

The utilization of algal ingredients for producing functional products has garnered significant attention. Furthermore, increasing the yield of polysaccharides has become a crucial point. In this work, the efficiencies of two-step extraction and co-extraction were compared, and dimethylamine solution was selected as the optimal extractant. Under the optimum extraction conditions (temperature of 75.00 °C, time of 3.15 h, liquid-solid ratio of 35.00 mL/g) determined by response surface methodology, the yield of alginate was 16.05 ± 0.37 % and the yield of fucoidan was 2.85 ± 0.08 %. Kinetic analysis of the extraction process was conducted using the shrinking core model, elucidating the rate and mechanism of product release. Additionally, it was demonstrated that the dimethylamine solution could be recycled for five times with stable extraction performance. The extraction mechanism was further analyzed by quantum chemical calculations, providing theoretical support for the extraction process of the products. The above results demonstrated that the higher yield of products extracted with dimethylamine was confirmed through experimental and quantum chemical analysis. Overall, this study provides a new perspective on the extraction of alginate and fucoidan from seaweed.

Extraction and Characterization of Cellulose from Kelp (Laminaria japonica) Residue

Abstract Kelp residue is the byproduct of industrial production of sodium alginate from kelp. An in-depth utilization of kelp residue not only creates higher economic value but also opens up a new pathway for comprehensive utilization of kelp. In this study, a method of first removing acid-soluble ash and then depleting protein was employed to extract cellulose components from kelp residue. Single-factor experiments demonstrated that treating kelp residue with 1.2 mol/L hydrochloric acid at a solid-liquid ratio of 1:5 effectively removed acid-soluble ash. Subsequently, further treatment with 3% NaOH at a solid-liquid ratio of 1:10, conducted at 100 °C for 140 minutes, reduced the protein content in the extract to below 1%, with a cellulose yield of 33.5%. Fourier transform infrared spectroscopy analysis revealed that characteristic peaks attributed to cellulose existed in the extractive, while electron microscopy observations indicated that the extracted kelp residue cellulose exhibited irregular thin-sheet structures. The cellulose obtained in this study lays the foundation for its further utilization and processing into cellulose-derived products.

Study on the Remediation of Groundwater Nitrate Pollution by Pretreated Wheat Straw and Woodchips

Groundwater nitrate contamination poses a threat to both the ecological environment and human health. This study investigated the potential of using saturated Ca(OH)2 to pretreat wheat straw and woodchips, aiming to enhance their efficacy as carbon sources for denitrification. The optimization of pretreatment conditions, and the elucidation of underlying mechanisms were explored. The pretreatment process involved the dissolution of lignin and hemicellulose, exposure of the cellulose structure, reduction of hydrogen bonds within cellulose, hydrolysis of polymerized cellulose, and the formation of cracks and hierarchical structures on the surface of the carbon source. These alterations improved the attachment and utilization of microorganisms. The maximum enzymatic reducing sugar yields for wheat straw and woodchips were achieved at solid-liquid ratios of 1:40 and soaking times of 5 and 2 days, respectively. The response surface predicted the optimal pretreatment conditions for wheat straw to be a solid-liquid ratio of 1:88.1 and a soaking time of 8.2 hours. Alkaline treatment increased the denitrification rate of woodchips by fivefold and prevented the initial organic matter leaching rate of wheat straw, thereby reducing the risk of secondary pollution. The predominant microbial communities in all samples exhibited functions related to lignocellulose degradation and denitrification. The community composition of solid-phase carbon sources was found to be richer than that of liquid-phase carbon sources, and the pretreatment increased the abundance of lignocellulose degradation and denitrification functional microorganisms. The pretreatment liquid of wheat straw achieved the highest denitrification rate constant (0.43 h-1). Our result validated the feasibility of using the pretreatment liquid as a denitrification carbon source and presenting a novel approach for waste resource utilization.

Microwave-Assisted vs. Conventional Extraction of Moringa oleifera Seed Oil: Process Optimization and Efficiency Comparison.

This study aims to evaluate the effectiveness of microwave-assisted and conventional extraction using ethanol, hexane, and petroleum ether as solvents, and to optimize the process for extracting oil from Moringa oleifera Lam. seeds, with a focus on improving food-grade oil production. Response surface methodology (RSM) was applied to enhance the extraction process of the oil. Central composite rotational design (CCRD) was used to analyze the impact of solid-liquid ratio (x1), power (x2), and temperature (x3) on oil yield. The optimization identified the optimal conditions as a solid/liquid ratio of 1:38, power of 175 W, and temperature of 50 °C, achieving a 42% oil yield. Notably, the microwave-assisted extraction reduced the processing time from 8 h (using conventional Soxhlet extraction) to just 1 h. Conventional extraction with hexane and petroleum ether was also performed for comparison, resulting in similar oil content and fatty acid profiles, predominantly, oleic acid. FTIR analysis confirmed that the microwave-extracted oil contained fatty acids and had similar characteristics to the conventionally extracted oil. Thus, the use of ethanol as a green solvent in the microwave has shown significant improvement in terms of time and energy savings compared to the Soxhlet method with toxic solvents. This study concludes that microwave-assisted extraction with ethanol provides a more energy efficient, environmentally friendly, and time-saving alternative for food-grade oil production, aligning with advancements in food engineering and production.

Optimization of Ultrasonic-Assisted Extraction, Characterization and Antioxidant and Immunoregulatory Activities of Arthrospira platensis Polysaccharides.

This study aimed to enhance the ultrasonic-assisted extraction (UAE) yield of seawater Arthrospira platensis polysaccharides (APPs) and investigate its structural characteristics and bioactivities. The optimization of UAE achieved a maximum crude polysaccharides yield of 14.78%. The optimal extraction conditions were a liquid-solid ratio of 30.00 mL/g, extraction temperature of 81 °C, ultrasonic power at 92 W and extraction time at 30 min. After purification through cellulose DEAE-52 and Sephadex G-100 columns, two polysaccharide elutions (APP-1 and APP-2) were obtained. APP-2 had stronger antioxidant and immunoregulatory activities than APP-1, thus the characterization of APP-2 was conducted. APP-2 was an acidic polysaccharide consisting of rhamnose, glucose, mannose and glucuronic acid at a ratio of 1.00:24.21:7.63:1.53. It possessed a molecular weight of 72.48 kDa. Additionally, APP-2 had linear and irregular spherical particles and amorphous structures, which contained pyranoid polysaccharides with alpha/beta glycosidic bonds. These findings offered the foundation for APP-2 as an antioxidant and immunomodulator applied in the food, pharmaceutical and cosmetic industries.

Leaching Thermodynamics of Low-Grade Copper Oxide Ore from [(NH4)2SO4]-NH3-H2O Solution.

This paper describes a highly alkaline low-grade copper oxide ore. Copper can be selectively leached out while other metals are retained. A thermodynamic model of the CuO-(NH4)2SO4-NH3-H2O system was established for the leaching of tenorite (CuO) under conditions of mass and charge conservation. MATLAB's fitting functions, along with the diff and solve functions, were used to calculate the optimal ammonia concentration and total copper ion concentration of tenorite under different ammonium sulfate concentrations. The effects of various ammonia-ammonium salt solutions (ammonium sulfate, ammonium carbonate, ammonium chloride) on the copper leaching rate were investigated. Results show that under the conditions of an ammonia concentration of 1.2 mol/L, an ammonia-ammonium ratio of 2:1, a liquid-solid ratio of 3:1, a temperature of 25 °C, and a leaching time of 4 h, the copper leaching rate from the ammonium sulfate and ammonium chloride solutions reaches 70%, which is slightly higher than that of ammonium carbonate. Therefore, an ammonia-ammonium sulfate system is selected for leaching low-grade copper oxide due to its lower corrosion to equipment compared to the chlorination system. The impact of this study on industrial applications includes the potential to find more sustainable and cost-effective methods for resource recovery. The industry can reduce its dependence on resources and mitigate its environmental impact. Readers engaged in low-grade oxidized copper research will benefit from this study.

Extraction of camptothecin and 10-hydroxycamptothecin from Camptotheca acuminata fruits by natural deep eutectic solvent

A natural deep eutectic solvent-based ultrasound-assisted simultaneous extraction (NADES-UAE) of camptothecin (CPT) and 10-hydroxycamptothecin (10-HCPT) was established. The 1.31 mg of CPT and 1.66 mg of 10-HCPT were obtained from each gram of the fruit powder of Camptotheca acuminata under the optimum conditions with a water content of 20%, a liquid-solid ratio of 12 mL/g and an ultrasound time of 20 min. The recovery efficiencies of CPT and 10-HCPT after AB-8 resin enrichment were 70.5% and 74.8%, respectively. The stronger interaction between NADES3 which was screened from 12 kinds of NADES and target components compared with methanol or water was demonstrated using molecular dynamics simulation. Moreover, the recovered NADES3 could be reused at least 4 times. The present research provided an efficient, environment-friendly, and sustainable method for extracting and recovering CPT and 10-HCPT from the fruits of C. acuminata.

Synthesis of bifunctional copolymeric nanofibers with selective extracting U(VI) from the solution and antibacterial property

Facing the problem of future nuclear fuel shortage, developing high-performance adsorbent materials is key. In this work, the amidoxime group/imidazole functionalized ionic liquid copolymer fibers containing bromide salts, and fluoroborate salts (namely P(AO/VEIMBr)8 and P(AO/VEIMBF4)6) were prepared by a one-pot method and free radical polymerization, hydroxyl amination reaction and electrostatic spinning, and characterized by SEM, FT-IR, and 1 H NMR. The influence of solid-liquid ratio, ionic strength, and adsorption time on the adsorption performance was investigated by batch adsorption experiments. In the meanwhile, the adsorption kinetics and thermodynamic processes of U(VI) on the copolymer fibers was also studied. Adsorption mechanism of U (VI) on polymer fibers was explored by XPS spectroscopic analysis combined with DFT method. Finally, the antimicrobial properties of the copolymer fibers were tested. The experimental results showed that the polymer nanofibers synthesized for U(VI) has a fast adsorption, high adsorption capacity at ionic strength close to seawater, and excellent reusability. The adsorption process conformed to the pseudo-second-order kinetic model and Langmuir model, which indicated that chemical adsorption and monolayer adsorption are dominant for adsorption U(VI) on the polymer nanofibers, and exhibits the highest Uranium adsorption capacity (76.92 mg/g and 81.96 mg/g at pH=8.1+0.1, respectively). XPS result showed the amine nitrogen and oxime oxygen in the amidoxime functional group were coordinated with uranyl(VI) ions. The antibacterial experiments showed that the copolymer fibers have antimicrobial properties and the antibacterial rate is over 90 %. Therefore, the nanofibers may be a promising material for extracting uranium from the weak alkaline wastewater or seawater.

Ultrasound-Assisted Enzyme Extraction, Physicochemical Properties and Antioxidant Activity of Polysaccharides from Cordyceps militaris Solid Medium.

Cordyceps militaris solid medium polysaccharides (CMMPs) were extracted using an ultrasound-assisted enzyme method, and the process conditions were optimized via response surface methodology (RSM). The CMMPs were separated into four components named CMMP-1, CMMP-2, CMMP-3 and CMMP-4 using ethanol fractional precipitation, and their monosaccharide composition and structural properties were analyzed by molecular weight analysis, Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), Congo red test, ultraviolet-visible spectroscopy (UV-vis), atomic force microscopy (AFM), and thermogravimetric analysis (TGA). RSM could predict the yield of the CMMP (R2 = 0.9928), and the polysaccharide yield was 15.43% under the selected conditions of 3.1% cellulase enzyme addition, a liquid-solid ratio of 42:1, an extraction temperature of 61 °C, and an extraction time of 60 min. Glucose and galactose were the main constituents of the four fractional precipitated polysaccharides. Furthermore, four components exhibited antioxidant activity, and CMMP-1 demonstrated stronger antioxidant activity in vitro. This study demonstrates the possibility of developing a natural antioxidant food from Cordyceps militaris solid medium.

Ultrasound-assisted extraction, optimization, and purification of total flavonoids from [formula omitted] and analysis of their antioxidant, anti-inflammatory, and analgesic activities

Daphne genkwa (D. genkwa) is the dried flower buds of a Chinese medicinal plant with multiple biological activities. Response surface methodology (RSM) combined with artificial neural network (ANN) techniques were utilized to optimize ultrasound-assisted extraction conditions for D. genkwa. Antioxidant activity and anti-inflammatory and analgesic properties of total flavonoids from D. genkwa (TFDG) were assessed. Optimal conditions involving ultrasonic power of 225 W, 30 min extraction time, 30 mL/g liquid–solid ratio, 60 °C extraction temperature, and 70% ethanol concentration yielded a maximum total flavonoids content (TFC) of 5.41 mg/g. After microporous resin purification, four specific flavonoids in D. genkwa were identified and quantified using high-performance liquid chromatography (HPLC). The TFDG demonstrated potent antioxidant activity, with a 94% rate of scavenging the 2, 2-diphenyl-1-picrylhydrazyl (DPPH). Furthermore, TFDG exhibited pain-alleviating properties in hot plate and acetic acid-induced writhing tests and noteworthy inhibitory effects on xylene-induced ear swelling in mice. The total flavonoids extracted by ultrasound had excellent biological activity. This establishes a foundation for further investigation into the potential medical value of D. genkwa.

Impacts of alkaline washing pretreatment on municipal solid waste incineration fly ash (MSWI FA) and resulting geopolymers

The safe disposal and utilization of municipal solid waste incineration fly ash (MSWI FA) has emerged as a crucial challenge, primarily due to elevated levels of heavy metals and chlorides. In this study, the influence of key factors in different pretreatment methods on the physicochemical properties of MSWI FA was analyzed, and the effects and mechanism of different pretreatment methods on the resulting geopolymers were studied. Under the conditions of a liquid-solid ratio (L/S) of 7 mL/g, a rotational speed of 500 r/min, and a stirring time of 20 min, the alkali washing with 1 mol/L NaOH solution exhibited better effect than water washing. The total content of chlorides and the content of soluble chloride in AFA (MSWI FA with alkali washing) were 1.53 % and 0.85 %, respectively. Alkali washing had a greater influence on the migration of heavy metals from MSWI FA to filtrate than water washing. Meanwhile, alkaline washing exhibited better effect in calcium retention and sulfur removal. The pretreatment process enhanced the gel formation in geopolymers, subsequently exerting a significant influence on the compressive strength and leaching concentration of heavy metals. Thermogravimetric analysis showed the bound water content in AG (8.46 %) was the greatest in all simples, indicating that exerted the most pronounced impact on the gel formation during geopolymerization. And, the lower ratio of Si-O-Na to Si-O-T in AG (0.20) indicated a longer geopolymeric chains, which explained the higher compressive strength of geopolymers during the initial curing period. This article provides a new pretreatment method to promote the resource utilization of MSWI FA.

Optimization of Ultrasound-Assisted Extraction of Phenolics from Satureja hortensis L. and Antioxidant Activity: Response Surface Methodology Approach

The extract of the plant species Satureja hortensis L. (often used as traditional ethno-therapy and in food processing) was prepared using the ultrasonic extraction technique, and contains a large quantity of secondary metabolites, with scientific evidence for antioxidant, antimicrobial, sedative, antispastic and antidiarrheal activities. Process optimization was carried out using a mathematical–statistical method (response surface methodology—RSM), which models and examines the effects of three levels and three variables on the observed response. The investigated responses were the content of total phenolic components (TPC) and total flavonoids (TFC), as well as tests of antioxidant activity at the level of radicals. The independent variables were ethanol concentration (40–80%), temperature (40–80 °C) and the liquid–solid ratio (10–30 mL/g). Results from this study were entered into a second-degree polynomial with multiple non-linear regression. Analysis of variance (ANOVA) was applied to find the most favorable environment for assessing the model’s performance and effectiveness with an ethanol concentration of 20%, temperature of 80 °C and LSR of 21.4 mL/g. ANOVA assessed the model’s significance, and a second-order polynomial model described the relationships between variables and responses. Diagnostic plots confirmed the model’s adequacy and reliability. The estimated values were 4.11 mg chlorogenic acid equivalents per gram of dry weight (CEA/g), 2.18 mg of rutin equivalents per gram of dry weight (RE/g), and 0.030 mg/mL and 0.030 mg/mL for TPC, TFC, IC50 and EC50, respectively. High-Performance Liquid Chromatography with diode array detection (HPLC-DAD) examination revealed that the prominent substance in the tested extract is rosmarinic acid (46,172 µg/mL), followed by chlorogenic acid (1519 µg/mL).

Advanced membrane contactor coupled with electrodialysis metathesis for efficient carbon dioxide capture and waste salt remediation

Rapid development of society has led to significant increases in carbon dioxide (CO2) emissions, primarily driven by intensified industrial activities and urbanization. Capture and utilization of CO2 not only mitigate greenhouse gas emissions but also support the transition towards a circular economy by recycling CO2 into high-value products. This study proposed a membrane contactor and electrodialysis metathesis (MC-EDM) for CO2 capture, NH4HCO3 generation, and NaHCO3 conversion. The MC facilitated the selective capture of CO2 from gas streams. Concurrently, EDM enhanced the NaHCO3/NH4Cl conversion from NH4HCO3/NaCl through selective ion transport mechanisms. The key influencing factors (e.g., gas flow rate, liquid flow rate, and ammonia concentration) for the MC process were optimized to achieve 1.014 mol/L NH4HCO3 concentration with 88.73 % yield and 78.94 % CO2 removal efficiency. Moreover, the parameters (e.g., solid-liquid ratio, membrane type, operating voltage, and salt component ratio) for the EDM process were optimized to achieve NaHCO3 with a 90.9 % yield and 97.80 % purity. Economic analysis indicated the overall process for NaHCO3 recovery was approximately 0.3267 $/kg. The cyclic experiments demonstrated the stability of MC-EDM for high-value NaHCO3 recovery. Thus, the MC-EDM pathways contribute significantly to reducing greenhouse gas emissions from industrial processes while promoting resource efficiency and economic sustainability.

Sintering Mechanism and Leaching Kinetics of Low-Grade Mixed Lithium Ore and Limestone

With the rapid development of new energy fields and the current shortage of lithium supply, an efficient, clean, and stable lithium resource extraction process is urgently necessary. In this paper, various advanced detection methods were utilized to conduct a mineralogical analysis of the raw ore and systematically study the occurrence state of lithium; the limestone sintering process was strengthened and optimized, elucidating the sintering mechanism and analyzing the leaching process kinetics. Under an ingredient ratio of 1:3, a sample particle size of 300 mesh, a sintering temperature of 1100 °C, a sintering time of 3 h, a liquid–solid ratio of 2:1, a leaching temperature of 95 °C, and a leaching time of 1 h, the leaching rate of Li reached 90.04%. The highly active Ca–O combined with Si–O on the surface of β–spodumene to CaSiO4, and Al–O was isolated and combined with Li to LiAlO2, which was beneficial for the leaching process. The leaching process was controlled by both surface chemical reactions and diffusion processes, and Ea was 27.18 kJ/mol. These studies provide theoretical guidance for the subsequent re-optimization of the process.

Electron beam irradiation coupled ultrasound-assisted natural deep eutectic solvents extraction: A green and efficient extraction strategy for proanthocyanidin from walnut green husk

Proanthocyanidin (PAC) is recognized as a potent natural antioxidant that prevents various diseases. As societal awareness increases, eco-friendly and efficient natural product extraction technologies are gaining more attention. In this study, an electron beam irradiation (EBI) coupled with ultrasound-assisted natural deep eutectic solvents (NADES) extraction method was developed to enable the green and highly efficient extraction of PAC from walnut green husk (WGH). NADES, prepared with choline chloride and ethylene glycol, demonstrated excellent extraction capacity and storage stability for PAC. Molecular dynamics simulations elucidated the high compatibility between NADES and PAC, attributed mainly to a higher SASA value (207.85 nm2), a greater number of hydrogen bonds (330.99), an extended hydrogen bonding lifetime (4.54 ps), and lower inter-molecular interaction energy. Based on these findings, the optimal conditions (13 kGy EBI, 42 mL/g liquid-solid ratio, 38 °C extraction temperature, 70 min extraction time) resulted in a maximum PAC extraction yield of 56.34 mg/g. Notably, this yield was 32.93 % higher than that observed in samples not treated with EBI and ultrasound-assisted extraction (UAE). Analysis of tissue morphology, extract functional groups and thermal behavior suggested a possible mechanism for the synergistically enhanced PAC extraction by the EBI-NADES-UAE method. Additionally, the PAC extracted using the NADES by the EBI coupled with ultrasound-assisted method exhibited outstanding antioxidant activity (comparable to Vc), digestive enzyme inhibition (IC50: 17–0.61 mg/mL), and anti-glycation capacity (IC50: 86.49 μg/mL). Overall, this work provided a green and efficient strategy for PAC extraction from WGH, elucidated the extraction mechanism and bioactivities, and offered valuable insights for potential industrial applications.

The total tannins of Geum japonicum Thunb. var. chinense extracted by green and natural deep eutectic solvent: Extraction optimization, component identification and hypoglycemic activity

Geum japonicum Thunb. var. chinense (G. japonicum) is a cultivated medicinal plant and used as folk medicine, among which tannins are the main active ingredients. In this work, L-proline-lactic acid (Pro:La) as natural deep eutectic solvents (NADESs) was tailored for the total tannins extraction from G. japonicum with the optimal conditions as follows: water content of 29 %, solid-liquid ratio of 27:1 (mg/mL), extraction time of 48 min, and extraction temperature of 48°C. In high fat diet-induced obese mice, the total tannin extract of G. japonicum can significantly reduce the body weight and serum lipid levels, improve glucose tolerance impairment and insulin resistance, reduce islet hypertrophy and protect the liver. Targeted fractionation of the total tannin extract of G. japonicum led to the isolation of sixteen tannins. Notably, the isolated tannins, except for ellagic acid and 3,3′-di-O-methylellagic acid, possessed strong α-glucosidase inhibitory activities (IC50: 1.401–4.801 μg/mL) and dose-dependently inhibited glucose consumption of Caco-2 model system in vitro. These results indicate that the NADES (Pro:La) can effectively extract total tannins from G. japonicum and provide a reference for further applications in medicine and healthcare products.

Continuous oxidation of organic contaminates in soil by polylactic acid-coated KMnO4

Potassium permanganate (KMnO4), as a versatile and safe solid source of MnO4-, received substantial attention from researchers as a potential soil oxidant reagent. In this study, we prepared polylactic acid (PLA)-coated KMnO4 (KMnO4@PLA) to control MnO4- release. The experimental results indicated that the optimal preparation scheme for KMnO4@PLA was a particle size of 1–2 mm, a solid-liquid ratio of 1:3, and a core-shell ratio of 1:3. And the release lifetimes of MnO4- from KMnO4@PLA in aqueous and quartz sand media were 200 hours and 310 hours, respectively, which were 2400 and 33 times longer than the release lifetimes of raw KMnO4. The controlled release of MnO4- from KMnO4@PLA was achieved through the hydrolysis of PLA. And the release process adhered to first-order reaction kinetics and displayed Fickian diffusion characteristics. Moreover, the removal of phenol by KMnO4@PLA in aqueous, quartz sand, and soil media were investigated through batch and flow column experiments. Compared with the raw KMnO4, the KMnO4@PLA exhibited a stronger ability to degrade phenol, due to the mildly acidic nature of the PLA shell. These findings demonstrated that KMnO4@PLA has significant advantages for the remediation of organically contaminated soils.