An efficient approach for the extraction of orientin and vitexin from Trollius chinensis flowers using ultrasonic circulating technique

A modified strategy to improve the dissolution of flavonoids from Artemisiae Argyi Folium using ultrasonic-assisted enzyme-deep eutectic solvent system

In this study, enzyme-deep eutectic solvent-assisted ultrasonic extraction technique (EnDUE) was developed for the efficient dissolution of flavonoids from Artemisiae Argyi Folium. The extraction results of Artemisiae Argyi Folium flavonoids (quercetin, luteolin, and isorhamnetin) were used as indicators to investigate the influencing factors through single factor experiment, Placket-burman design, and Box-behnken design, so as to obtain satisfactory yields. After systematic optimization, the optimal conditions for extraction of the target flavonoids were: Choline chloride/1,4-butanediol with a water content of 25%, cellulase+pectinase with a concentration of 1.6%, solid-liquid ratio of 1/32 g/mL, pH of 4.2, ultrasonic frequency of 80 kHz, ultrasonic power of 160 W, ultrasonic temperature of 40 °C, and ultrasonic time of 25 min, respectively, which derived a total yield of 8.06 ± 0.29 mg/g. Compared with the reference techniques, the proposed EnDUE technique showed significant advantages in the yield and extraction efficiency of flavonoids. In addition, after preliminary purification, the Artemisiae Argyi Folium flavonoids showed good antioxidant activity. Deep eutectic solvent (DES) can degrade the cell wall components and increase the action site of enzyme, and enzyme can promote the penetration of DES into the cell wall matrix, which is mutually beneficial to the dissolution of intracellular components. Therefore, the extraction technique proposed in this work (EnDUE) greatly promotes the dissolution of flavonoids from Artemisiae Argyi Folium, and provides theoretical support for the further application of plant flavonoids.

Density-oriented deep eutectic solvent-based system for the selective separation of polysaccharides from Astragalus membranaceus var. Mongholicus under ultrasound-assisted conditions

The water extraction and ethanol precipitation method is an extraction method based on the solubility characteristics of polysaccharides that offers wide applicability in the extraction and separation of plant polysaccharides. However, this method leads to large amounts of proteins, nucleic acids, pigments, and other impurities in the polysaccharides products, which makes downstream purification complicated and time-consuming. In this study, a green, high-density natural deep eutectic solvents was used for the high-purity extraction and separation of polysaccharides from Astragalus membranaceus (Fisch) Bge. var. Mongholicus (Bge.) Hsiao roots under ultrasound-assisted conditions. In this study, 16 different natural deep eutectic solvents were designed to screen the best solvent for extracting Astragalus polysaccharides (APSs). Based on the yield and recovery of APSs, a natural deep eutectic solvents composed of choline chloride and oxalic acid with a molar ratio of 1:2 was selected. The related factors affecting polysaccharides extraction and solvent precipitation were investigated. To improve the operating methodology, single-factor trials, a Plackett-Burman design, and a Box-Behnken design were used. The optimal extraction process conditions were obtained as follows: water content of 55%, liquid-solid ratio of 24 mL/g, ultrasonic irradiation time of 54 min, ultrasonic irradiation temperature of 50 °C, ultrasonic irradiation power of 480 W, ethanol precipitation time of 24 h, and ethanol concentration of 75%. Under optimal extraction conditions, the recovery of APSs was 61.4 ± 0.6 mg/g. Considering the special matrix characteristics of A. membranaceus var. Mongholicus roots, physical-technology-based ultrasonic waves promote penetration, and the mass transfer function also solves the bottleneck of high-viscosity deep eutectic solvents in the extraction stage. In comparison with the conventional method, the proposed method based on deep eutectic solvents isolation can significantly increase APSs recovery, which is beneficial to simplifying the process of polysaccharides purification by using solvent properties to separate extracts and reduce impurities in APSs.

Extraction of Phenolic and Flavonoid Compounds from Mung Bean (Vigna radiata L.) Seed Coat by Pressurized Liquid Extraction

Mung bean seed coat (MBC) is a by-product of the mung bean processing industry. It contains a large number of phenolic compounds with therapeutic anti-inflammatory, anti-diabetic and antioxidant properties. This research aimed to investigate the optimum conditions for phenolic and flavonoid extraction from MBC by pressurized liquid extraction (PLE). Response surface methodology (RSM) was used to study the effects of temperature (80-160 °C), pressure (1200-1800 psi) and ethanol concentration (5-95%) on total phenolic content (TPC), total flavonoid content (TFC) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) scavenging activity (ABTS). Scale-up extraction was also performed. The optimum conditions for extraction were 160 °C, 1300 psi and 50% ethanol. Under optimum conditions, the TPC was 55.27 ± 1.14 mg gallic acid equivalent (GAE)/g MBC, TFC was 34.04 ± 0.72 mg catechin equivalent (CE)/g MBC and ABTS scavenging activity was 195.05 ± 2.29 mg trolox equivalent (TE)/g MBC. The TFC and ABTS scavenging activity of the extracts obtained at the pilot scale (10 L) was not significantly different from the laboratory scale, while TPC was significantly increased. The freeze-dried MBC extract contained vitexin and isovitexin 130.53 ± 17.89, 21.21 ± 3.22 mg/g extract, respectively. In conclusion, PLE was able to extract phenolics, flavonoids with ABTS scavenging activity from MBC with the prospect for future scale-up for food industry.

Ultrasonic Microwave-Assisted Micelle Combined with Fungal Pretreatment of Eucommia ulmoides Leaves Significantly Improved the Extraction Efficiency of Total Flavonoids and Gutta-Percha

A biological pretreatment of Eucommia ulmoides leaf biomass was carried out. Above all, the total flavonoids were isolated from Eucommia ulmoides leaves by the treatment of alkaline solution of sodium dodecyl benzene sulfonate combined with ultrasonic microwave. The extraction parameters were optimized by central composite design (CCD) software and were displayed as follows: surfactant concentration of 1.5%, microwave power of 700 W, extraction time of 30 min, and liquid-solid ratio of 50 mL/g. The actual yield of total flavonoids was 1.45%. The results of Sudan III color development showed that the cuticle of Eucommia ulmoides leaves was completely removed after dilute alkali pretreatment. Then, Eucommia ulmoides leaves were fermented by Trichoderma viride to remove the holocellulose and obtain gutta-percha. The content of cellulose and hemicellulose in Eucommia ulmoides leaves obviously decreased after Trichoderma viride fermentation. The optimum parameters were listed as follows: solid-liquid ratio of 0.06 g/mL, four extraction times, extraction time of 89.72 min, and extraction temperature of 85 °C. The actual yield of gutta-percha was 4.38%. The amount of extraction solvent per unit weight of gutta-percha from untreated Eucommia ulmoides leaves was 2.91 mL/mg, while that from leaves treated by Trichoderma viride was only 0.96 mL/mg. The amount of extraction solvent was grossly reduced, which is beneficial in terms of environmental protection. The characterizations of gutta-percha were verified by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and proton nuclear magnetic resonance (¹H NMR). This study laid a certain theoretical and experimental basis for the multi-stage extraction of Eucommia ulmoides leaves and the utilization of Eucommia ulmoides resources.

Efficient Production of Orientin and Vitexin from Luteolin and Apigenin Using Coupled Catalysis of Glycosyltransferase and Sucrose Synthase

Orientin and vitexin are flavone 8-C-glycosides that exhibit many biological characteristics. This study aimed to establish a two-enzyme-coupled catalytic strategy to enhance the biosynthesis of orientin and vitexin from apigenin and luteolin, respectively. The C-glucosyltransferase (TcCGT1) gene from Trollius chinensis was cloned and expressed in Escherichia coli BL21(DE3). The optimal activity of TcCGT1 was achieved at pH 9.0 and 37 °C. TcCGT1 was relatively stable over the pH range of 7.0-10.0 at a temperature lower than 45 °C. The coupled catalytic strategy of TcCGT1 and different sucrose synthases was adopted to enhance the production of orientin and vitexin. By optimizing the coupling reaction conditions, orientin and vitexin production successfully achieved 2324.4 and 5524.1 mg/L with a yield of 91.4 and 89.3% (mol/mol), respectively. The coupled catalytic strategy proposed in this study might serve as a promising candidate for the large-scale production of orientin and vitexin in the future.

Effect of Syringopicroside Extracted from Syringa oblata Lindl on the Biofilm Formation of Streptococcus suis

Syringopicroside is a natural drug with antibacterial activity, which is the main ingredient of Syringa oblata Lindl (S. oblata). In order to further develop the application of S. oblata and evaluate the ability of syringopicroside against Streptococcus suis (S. suis), this investigation first applied an ultrasonic-assisted method to extract syringopicroside, and then response surface methodology (RSM) was performed to get the optimum condition. Based on RSM analysis, a second-order polynomial equation about the syringopicroside yield and four variables, including ultrasonic power, time, temperature, and liquid-to-solid ratio, was purposed. Through RSM prediction and model verification experiments, the optimum conditions were determined, as follows: ultrasonic time was 63 min, temperature was 60 °C, a liquid-to-solid ratio was set to 63 mL/g, and ultrasonic power was 835 W. Under this condition, a high syringopicroside yield was obtained (3.07 ± 0.13 mg/g), which was not significantly different with a predicated value. After separation and purification by HPD 500 microporous resin, then mass spectrum was applied to identify the main ingredient in aqueous extract. A minimal inhibitory concentration (MIC) assay revealed the value against S. suis of syringopicroside was 2.56 µg/µL and syringopicroside with sub-inhibitory concentrations that could effectively inhibit biofilm formation of S. suis. Besides, scanning electron microscopy analysis indicated syringopicroside could destroy the multi-layered aggregation structure of S. suis. Finally, molecular docking analysis confirmed that syringopicroside was combined with Orfy protein of S. suis through hydrogen bonds, hydrophobic interaction, and π-π stacking.

Ultrasonic-enhanced surface-active ionic liquid-based extraction and defoaming for the extraction of psoralen and isopsoralen from Psoralea corylifolia seeds

Recently, integrated and sustainable methods for extracting active substances from plant materials using green solvents, i.e., ionic liquids, have gained increasing attention. Ionic liquids showsuperiority over conventional organic solvents; however, they also exhibit negative factors and problems, such as high viscosity, poor water intermiscibility, intensive foaming and poor affinity for fat-soluble substances. The proposed method utilizes ultrasonic-enhanced surface-active ionic liquid-based extraction and defoaming (UESILED) to improve the extraction efficiency of ionic liquids. Single-factor experiments and a Box-Behnken design (BBD) were utilized to optimize the extraction procedure. The optimal conditions were as follows: extraction solvent, [C₁₀MIM]Br; ultrasonic treatment time, 28 min; ultrasonic irradiation power, 437 W; liquid-solid ratio, 10 mL/g; particle size, 60 ~ 80 mesh; ultrasonication temperature, 313 K; and [C₁₀MIM]Br solution concentration, 0.5 mol/L. In comparison with those of other reference extraction methods, the proposed method exhibited higher yields of two furocoumarins and operational feasibility. Moreover, the mechanism of UESILED was elaborated in terms of accelerating infiltration, dissolution and defoaming. The feasible and efficient ultrasonic-enhanced ionic liquid-based extraction established in this study strongly contributes to overcoming the limitations of ionic liquid solvents. The present research indicates that this improved process will be beneficial for the extraction of other fat-soluble substances and provides promising concepts and experimental data.

Magnetically stabilized bed packed with synthesized magnetic silicone loaded with ionic liquid particles for efficient enrichment of flavonoids from tree peony petals

In this work, synthesized magnetic silicone loaded with ionic liquid (Fe₃O₄@SiO₂@IL) particles combined with gas-liquid-solid magnetically stabilized bed (GLS-MSB) were applied to enrich flavonoids from tree peony petal extraction solution. The magnetic core (Fe₃O₄) encased in silica was conducive to its rapid and efficient separation, and the modification of silica with ionic liquids (ILs) could provide the functional groups for selective adsorption of flavonoids. Furthermore, the magnetic materials were evenly dispersed in the GLS-MSB system, realizing the adequate contact and causing the positive influence on the result. After physicochemical characterization, the prepared Fe₃O₄@SiO₂@IL (IL=VBimBr) particles were validated in the enrichment performance of flavonoids, including the type of ionic liquid loaded, desorption solution, adsorption and desorption kinetics. The adsorption kinetics obeyed the pseudo-second-order model, the adsorption isotherms were consistent with the Langmuir equation, and the adsorption process was spontaneous and exothermic. Additionally, the dynamic processes using GLS-MSB packed with Fe₃O₄@SiO₂@IL particles were evaluated systematically, deriving the optimum conditions (5 mL/min liquid flow rate, 130 mL Loading amount and 42.55 Oe magnetic field intensity) and improving the purity of flavonoids. After enrichment, the Fe₃O₄@SiO₂@IL particles were successfully recycled and reused. Overall, the developed method offers a great potential for the enrichment of flavonoids from natural materials.

Experimental and DFT studies on the ultrasonic energy-assisted extraction of the phytochemicals of Catharanthus roseus as green corrosion inhibitors for mild steel in NaCl medium

Catharanthus roseus (Apocynaceae family) extract is rich in organic phytochemicals such as alkaloids, polyphenolic compounds, and flavonoids. It contains several functional entities such as fused heterocycles, and hydroxyl and carbonyl groups, which could be useful for corrosion inhibition of mild steel in NaCl environments. In the present work, ultrasonic energy was used to obtain the ethanolic extracts of root and stem which were then tested as corrosion inhibitors for mild steel in the presence of 3.5% NaCl. The corrosion inhibition process was studied by UV-visible spectroscopy, Fourier transform infrared spectroscopy, atomic force microscopy, weight loss, and electrochemical methods. After immersing in the corrosive medium, the microstructures of mild steel were investigated by scanning electron microscopy, X-ray diffraction, and ellipsometry. The extract of C. roseus showed excellent adsorption on mild steel surface as confirmed by DFT calculations. The results indicate that the extract of C. roseus acts as a mixed type corrosion inhibitor, where the stem extract is the most efficient inhibitor in 3.5% NaCl solution possibly due to the higher active area of stem phytochemicals.

C. roseus phytochemicals are physisorbed on the 111 Fe surface, and the oxygen non-bonding electron chemisorbed on the polarized state 111 Fe surface.

Sono-physical and sono-chemical effects of ultrasound: Primary applications in extraction and freezing operations and influence on food components

Ultrasound is an advanced non-thermal food-processing technology that has received increasing amounts of interest as an alternative to, or an adjuvant method for, conventional processing techniques. This review explores the sono-physical and sono-chemical effects of ultrasound on food processing as it reviews two typical food-processing applications that are predominantly driven by sono-physical effects, namely ultrasound-assisted extraction (UAE) and ultrasound-assisted freezing (UAF), and the components modifications to food matrices that can be triggered by sono-chemical effects. Efficiency enhancements and quality improvements in products (and extracts) using ultrasound are discussed in terms of mechanism and principles for a range of food-matrix categories, while efforts to improve existing ultrasound-assist patterns was also seen. Furthermore, the progress of experimental ultrasonic equipments for UAE and UAF as food-processing technologies, the core of the development in food-processing techniques is considered. Moreover, sono-chemical reactions that are usually overlooked, such as degradation, oxidation and other particular chemical modifications that occur in common food components under specific conditions, and the influence on bioactivity, which was also affected by food processing to varying degrees, are also summarised. Further trends as well as some challenges for, and limitations of, ultrasound technology for food processing, with UAE and UAF used as examples herein, are also taken into consideration and possible future recommendations were made.

Optimization of the culture condition of Bacillus mucilaginous using Agaricus bisporus industrial wastewater by Plackett-Burman combined with Box-Behnken response surface method

In the present study, conditions for Bacillus mucilaginous fermentation using Agaricus bisporus wastewater as culture medium were optimized. We analyzed the total number of living B. mucilaginous in the fermentation broth using multispectral imaging flow cytometry. Single-factor experiments were carried out, where a Plackett–Burman design was used to screen out three factors from the original six factors of processing wastewater solubility, initial pH, inoculum size, liquid volume, culture temperature, and rotation speed that affected the total number of viable B. mucilaginous. The Box–Behnken response surface method was used to optimize interactions between the three main factors and predict optimal fermentation conditions. Factors significantly affecting the total number of viable B. mucilaginous, including shaking speed, culturing temperature, and initial pH, were investigated. The optimum conditions for B. mucilaginous fermentation in A. bisporus wastewater were a rotational speed of 195 rpm, culture temperature of 29 °C, initial pH of 6.5, solubility of 0.5%, 8% inoculation volume, and 90 mL liquid volume in a 250 mL flask, culture time of 48 h. Under these conditions, the concentration of total viable bacteria reached 2.16 ± 0.02 × 10⁸ Obj/mL, which meets the national standard. A. bisporus wastewater can be used for the cultivation of B. mucilaginous.

Vitexin alleviates ER-stress-activated apoptosis and the related inflammation in chondrocytes and inhibits the degeneration of cartilage in rats

Excessive extracellular matrix degradation and chondrocyte apoptosis are the pathological features of osteoarthritis (OA).

Effects of ultrasonic pretreatments on quality, energy consumption and sterilization of barley grass in freeze drying

Barley grass is a plant resource for rehabilitation therapy. Its processing requires retaining nutrition well for rehabilitation cure of consumers. To meet the aim as well as low energy consumption and microbiological safety of products, ultrasonic treatments (UT) were applied to bathing materials at different power levels (10, 30, 45, 60W/L) for 10mins. After treatments, the bathed barley grass (100g) was freeze-dried under vacuum -0.09MPa with fixed power of 2W/g. Parameters of color, microbial colony, energy consumption, glass transition temperature, moisture content, water activity, taste substances, contents of flavonoid and chlorophyll were determined after drying. In contrast with no treatment case, UT (45W/L) decreased drying time by 14% and decreased energy consumption by 19%; UT (60W/L) decreased total microbial colonies by 33%. Also, UT (30W/L) yielded contents of flavonoid (9.2/kg) and chlorophyll (10.5g/kg) of dried sample; UT power (10W/L) yielded the highest L^∗(51.5) and the lowest a^∗(-9.3) value. Simultaneously, UT leads to a higher glass transition temperature (Tg), lower water activity and produces less sourness and bitterness of dried products. Ultra-sonication is an alternative to improve quality, flavor and energy consumption of barley grass in freeze drying.

Determination of orientin in Trollius chinensis using ultrasound-assisted extraction and high performance liquid chromatography: Several often-overlooked sample preparation parameters in an ultrasonic bath

The erratic pressure intensities and cavitation exhibited in an ultrasonic bath pose various during practical application. To achieve the most efficient experimental design, this manuscript aims to discover violently sites that are subject to the effect of slight changes in position on cavitation and ultrasound intensity distributed in the ultrasonic bath. In addition, optimization several often over-looked ultrasound parameters and experimental conditions, are intended to place the reaction vessel properly and operate under suitable experimental conditions to obtain the maximum yield of target analyte. In this study, an investigation of the various ultrasound intensities and cavitation in ultrasonic bath space were conducted with the help of the orientin yield using ultrasound-assisted extraction. Conventional parameters such as the volume fraction of ethanol, liquid-solid ratio, ultrasound irradiation power, time and frequency, and reaction temperature were investigated, all of which affect the extractive yield factors. Also several often over-looked parameters such as the extraction vessel position in the ultrasonic bath base, the distance between the bottom of the extraction vessel and the ultrasonic bath base, the diameter, the shape and the texture of the extraction vessel, height of the liquid medium and the ultrasound propagating medium salt concentration in the ultrasonic bath were tested exhaustively in this study. These results can therefore serve as a guide to optimize the usage of the ultrasonic bath for future applications.