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Effects of ultrasonic-assisted extraction on bioactive compounds,volatile flavors and antioxidant activities of vine tea water extracts
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作者 Xiao-Long Zhou Wei-Jin Jiang +2 位作者 Ji Yu Mao-Jun Yao Yun-Tong Li 《Traditional Medicine Research》 2025年第1期73-81,共9页
Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in China.In vine tea processing,a large amount of broken tea is produced,which has low commercial value.Methods:This study investigat... Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in China.In vine tea processing,a large amount of broken tea is produced,which has low commercial value.Methods:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea extracts.Results:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid content.Gas chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted extraction.Specifically,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE extracts.In vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant activity.Conclusion:The findings suggest that extraction methods significantly influence the chemical composition and antioxidant properties of vine tea extracts.Ultrasonic-assisted extraction proved instrumental in elevating the DMY content in vine tea extracts,thereby enriching its flavor profile while maintaining its antioxidant properties. 展开更多
关键词 vine tea DIHYDROMYRICETIN ultrasonic-assisted extraction volatile aroma components
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Chemically bonded BiVO_(4)/Bi_(19)Cl_(3)S_(27) heterojunction with fast hole extraction dynamics for continuous CO_(2) photoreduction 被引量:2
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作者 Baojing Huang Xinxin Fu +5 位作者 Kai Wang Liang Wang Hualei Zhang Zhongyi Liu Bin Liu Jun Li 《Advanced Powder Materials》 2024年第1期13-21,共9页
Surface charge localization and inferior charge transfer efficiency seriously restrict the supply of reactive hydrogen and the reaction dynamics of CO_(2) photoreduction performance of photocatalysts.Herein,chemically... Surface charge localization and inferior charge transfer efficiency seriously restrict the supply of reactive hydrogen and the reaction dynamics of CO_(2) photoreduction performance of photocatalysts.Herein,chemically bonded BiVO_(4)/Bi_(19)Cl_(3)S_(27)(BVO/BCS)S-scheme heterojunction with a strong internal electric field is designed.Experimental and density function theory calculation results confirm that the elaborated heterojunction accelerates the vectorial migration of photogenerated charges from BiVO_(4) to Bi_(19)Cl_(3)S_(27) via the interfacial chemical bonding interactions(i.e.,Bi-O and Bi-S bonds)between Bi atoms of BVO and S atoms of BCS or Bi atoms of BCS and O atoms of BVO under light irradiation,breaking the interfacial barrier and surface charge localization of Bi_(19)Cl_(3)S_(27),and further decreasing the energy of reactive hydrogen generation,CO_(2) absorption and activation.The separation efficiency of photogenerated carriers is much more efficient than that counterpart individual in BVO/BCS S-scheme heterojunction system.As a result,BVO/BCS heterojunction exhibits a significantly improved continuous photocatalytic performance for CO_(2) reduction and the 24 h CO yield reaches 678.27μmol⋅g^(-1).This work provides an atomic-level insight into charge transfer kinetics and CO_(2) reduction mechanism in S-scheme heterojunction. 展开更多
关键词 extraction dynamics Activated hydrogen Interfacial chemical bonds S-scheme CO_(2)photoreduction
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Design method of extractant for liquid-liquid extraction based on elements and chemical bonds
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作者 Yuwen Wei Chunling Zhang +4 位作者 Yue Zhang Lili Wang Li Xia Xiaoyan Sun Shuguang Xiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期193-202,共10页
In the petrochemical industry process, the relative volatility between the components to be separated is close to one or the azeotrope that systems are difficult to separate. Liquid-liquid extraction is a common and e... In the petrochemical industry process, the relative volatility between the components to be separated is close to one or the azeotrope that systems are difficult to separate. Liquid-liquid extraction is a common and effective separation method, and selecting an extraction agent is the key to extraction technology research. In this paper, a design method of extractants based on elements and chemical bonds was proposed. A knowledge-based molecular design method was adopted to pre-select elements and chemical bond groups. The molecules were automatically synthesized according to specific combination rules to avoid the problem of “combination explosion” of molecules. The target properties of the extractant were set, and the extractant meeting the requirements was selected by predicting the correlation physical properties of the generated molecules. Based on the separation performance of the extractant in liquid-liquid extraction and the relative importance of each index, the fuzzy comprehensive evaluation membership function was established, the analytic hierarchy process determined the mass ratio of each index, and the consistency test results were passed. The results of case study based on quantum chemical analysis demonstrated that effective determination of extractants for the analysis of benzene-cyclohexane systems. The results unanimously prove that the method has important theoretical significance and application value. 展开更多
关键词 Molecular design Element and chemical bonds Molecular simulation THERMODYNAMICS Solvent extraction
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Extraction,chemical components,bioactive functions and adulteration identification of walnut oils:A review
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作者 Yuan Gao Jia Hu +6 位作者 Xia Su Qi Li Caihong Su Yongling Li Gaiqin Ma Siyu Zhang Xiuzhu Yu 《Grain & Oil Science and Technology》 CAS 2024年第1期30-41,共12页
Walnut oil is a functional wood oil known to researchers that may potentially be a large source of Chinese edible oils.There are various extraction methods for walnut oil,including traditional(pressing,solvent-and enz... Walnut oil is a functional wood oil known to researchers that may potentially be a large source of Chinese edible oils.There are various extraction methods for walnut oil,including traditional(pressing,solvent-and enzymeassisted extraction)and novel methods(microwave,ultrasound,supercritical CO_(2),subcritical and other extraction technologies).Walnut oil is rich in nutrients,including phytosterols,tocopherols,polyphenols,squalene and minerals.It provides many health benefits,such as antioxidant,antitumor,anti-inflammatory,antidiabetic and lipid metabolism-related functions.In addition,the authentication of walnut oil has received much research attention.The present review provides detailed research on walnut oil extraction,composition,health benefits and adulteration identification methods.The path toward further walnut oil improvement in the context of the market value of walnut oil is also discussed. 展开更多
关键词 extraction technology chemical composition Bioactive AUTHENTICATION
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Influence of Solvent onto Chemical Extraction of America-Type Coconut (Coco nucifera L.) Fbers: Analysis of Physicochemical, Mechanical and Morphological Properties
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作者 Delphine Korgai Gandai Zara Haman +4 位作者 Djoda Pagore Frederic Memtine Ndong Augustin Abdourhamane Nsangou Niraka Blaise Hambate Gomdje Valery 《Journal of Textile Science and Technology》 2024年第3期64-81,共18页
In this study, the natural fibers from Coconuts of the species Coco nucifera L. were Chemically extracted in different solvents such as sodium hydroxide (SH), acetone (AC) and sodium hydroxide-acetone (SHA) for their ... In this study, the natural fibers from Coconuts of the species Coco nucifera L. were Chemically extracted in different solvents such as sodium hydroxide (SH), acetone (AC) and sodium hydroxide-acetone (SHA) for their applications in the textile industries. Structural, morphological and physico-mechanical characterizations such as X-ray diffraction (XRD), Fourier transform infrared spectrometry (FTIR), scanned electron microscopy (SEM), measurements of density, Young’s modulus, water absorption rate and humidity were evaluated. The XRD and FTIR results show that Coco nucifera L. fibers contains type I cellulose. Mechanical characterizations were also carried out. These results show that by varying the different solvents used, the physico-chemical, mechanical and morphological properties of the fibers change, which implies that the solvent has an influence on the properties of these fibers. The fibers extracted by the sodium hydroxide-acetone mixture have a linear density of 1.636, the percentage of water absorption is 62.428%, the percentage of moisture absorption 9.605% compared to other values in the literature shows that this solvent mixture improves the properties of coconut fibers which contain type I cellulose. The tensile stress is 0.013 GPa, the percentage strain is 49.836% and the Young’s modulus is 0.114 GPa as well as the percentage elongation show that these fibers are elasto-plastic. The values obtained mean that these fibers are suitable for use in textiles. 展开更多
关键词 chemical extraction Cellulose Coco nucifera L. Fibers ELASTO-PLASTIC Textiles
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Optimization of Ultrasonic-assisted Extraction Process for Polysaccharide from Lactarius deliciosus by Response Surface Methodology and Its Antioxidant Activity
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作者 Bei LIU Ting DING +4 位作者 Yufeng ZHENG Fang WU Mi TIAN Qian WANG Ting HU 《Agricultural Biotechnology》 2024年第6期46-51,共6页
[Objectives]Polysaccharide was extracted from Lactarius deliciosus by ultrasonic-assisted method to improve polysaccharide yield.[Methods]Five variables including extraction temperature,extraction time,ultrasonic powe... [Objectives]Polysaccharide was extracted from Lactarius deliciosus by ultrasonic-assisted method to improve polysaccharide yield.[Methods]Five variables including extraction temperature,extraction time,ultrasonic power,ultrasonic time and material-to-liquid ratio were selected for single factor experiments.The extraction process of L.deliciosus polysaccharide was optimized by response surface analysis,and its antioxidant activity was evaluated by measuring its total reduction ability and DPPH free radical scavenging capacity.[Results]The optimal extraction conditions were determined as follows:material-to-liquid ratio 1:35 g:ml,ultrasonic power 462 W,ultrasonic time 10 min,extraction time 110 min and extraction temperature 90℃.Under these conditions,the extraction rate of polysaccharide was(10.83±0.03)%.The antioxidant test results showed that when the mass concentration of L.deliciosus polysaccharide was 0.5 mg/ml,its absorbance and DPPH free radical scavenging rate reached their maximum values,which were 3.274%and 41.27%,respectively.The L.deliciosus polysaccharide had good antioxidant properties.[Conclusions]This study provides a theoretical basis for further development and utilization of L.deliciosus polysaccharide in the future. 展开更多
关键词 Lactarius deliciosus POLYSACCHARIDE ultrasonic-assisted extraction Response surface analysis Antioxidant activity
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A Comparative Study on Chemical Composition of Supercritical CO_2 Extraction Products in Peels of Trichosanthes kirilowii Maxim. from Changqing District
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作者 于京平 李佳 +1 位作者 张永清 范英才 《Agricultural Science & Technology》 CAS 2013年第2期257-261,共5页
[Objective] This study aimed to investigate the differences in chemical composition of supercritical CO2 extraction products in peels of Trichosanthes kirilowii Maxim. from Changqing district. [Method] Supercritical f... [Objective] This study aimed to investigate the differences in chemical composition of supercritical CO2 extraction products in peels of Trichosanthes kirilowii Maxim. from Changqing district. [Method] Supercritical fluidextraction (SFE) and GCMS method were applied to determine and analyze the chemical components of the extracts in peels of three strains of Trichosanthes kirilowii Maxim. [Result] The chemical components of supercritical CO2 extraction products in peels of three strains of Trichosanthes kirilowii Maxim. varied., and the number of chemical components with normalized percentage content higher than 1% was 5, 7 and 8, respectively. There are 14 kinds of common components, and the relative content of hexadecanoic acid was the highest. [Conclusion] Supercritical CO2 extracts in peels of different strains of Trichosanthes kirilowii Maxim. contain different chemical components, providing scientific basis for breeding excellent varieties and the development and utilization of Trichosanthes kirilowii Maxim. 展开更多
关键词 Trichosanthes kirilowii Maxim. PEEL Supercritical CO2 extraction products chemical components COMPARISON
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Optimization of Ultrasonic-Assisted Extraction Process of Polysaccharides from American Ginseng and Evaluation of Its Immunostimulating Activity 被引量:7
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作者 YANG Xiu-shi WANG Li-jun +2 位作者 DONG Chuan Edmund Man King Lui REN Gui-xing 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第12期2807-2815,共9页
Ultrasonic-assisted extraction (UAE) of American ginseng polysaccharides (AGP) was investigated using response surface methodology. Three-factor-three-level Box-Behnken design was employed to optimize the ultrason... Ultrasonic-assisted extraction (UAE) of American ginseng polysaccharides (AGP) was investigated using response surface methodology. Three-factor-three-level Box-Behnken design was employed to optimize the ultrasonic power, extraction time and ratio of water to raw material to obtain a high AGP yield. The analysis of variance and response surface plots indicated that ultrasonic power was the most important factor affecting the extraction yield. The optimal conditions were ultrasonic power 400 W, extraction time 71 min, and ratio of water to raw material 33 mL g-1. Under these conditions, the yield of AGP was 8.09%, which was agreed closely to the predicted value. Gas chromatography (GC) analysis showed that AGP was composed of arabinose, rhamnose, galactose, glucose, and galacturonic acid. Fourier transform infrared spectra revealed the general characteristic absorption peaks of AGP. In addition, AGP exhibited good immunostimulating activities by up-regulating the production of nitric oxide and cytokines. Compared with hot water extraction, UAE required shorter extraction time and gave a higher extraction yield, without changing the structure and immunostimulating activity of AGP. The results indicated that UAE could be an effective and advisable technique for the large scale production of plant polysaccharides. 展开更多
关键词 ultrasonic-assisted extraction POLYSACCHARIDES American ginseng response surface methodology immunostimulating activity
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Antioxidant and hepatoprotective effects of Ajuga nipponensis extract by ultrasonic-assisted extraction 被引量:3
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作者 Chang-Wei Hsieh Wen-Ching Ko +3 位作者 Wai-Jane Ho Chao-Kai Chang Guo-Jhou Chen Jen-Chieh Tsai 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第5期409-414,共6页
Objective: To investigate suitable condition for extraction of the active components from Ajuga nipponensis(A. nipponensis). Methods: Orthogonal experimental design was used to determine the optimal extraction paramet... Objective: To investigate suitable condition for extraction of the active components from Ajuga nipponensis(A. nipponensis). Methods: Orthogonal experimental design was used to determine the optimal extraction parameters for ecdysterones and flavonoids. Finally, the hepatoprotective abilities of A. nipponensis extracts were evaluated by CCl_4-induced animal models. Results:Maximum yields of flavonoids(7.87±0.10) mg/g and ecdysterones(0.73±0.02) mg/g could be obtained when the extraction time was 50 min, the extraction temperature was 60 ℃, and the ratio of sample to 70%(v/v) ethanol was 1:20(w/w). The antioxidant property of A. nipponensis was correlated to the concentration of its extracts. At 5 mg/m L, A. nipponensisextract scavenged 84.8% of DPPH radical and had absorbance values of 2.43±0.04 reducing power. Upon CCl_4-induced liver injury, glutamic oxaloacetic transaminase and glutamic pyruvic transaminase decreased significantly after the mice were treated with A. nipponensis. Histological researches also explained that A. nipponensis reduced the extent of liver lesions induced by CCl_4. Conclusions: A. nipponensis exhibited potent antioxidant activity in chemical experimental models and hepatoprotective effect against CCl_4-induced liver damage. 展开更多
关键词 Ajuga nipponensis ultrasonic-assisted extraction ORTHOGONAL test ANTIOXIDANT HEPATOPROTECTION
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1Assessing Soil Available Potassium by Cation Exchange Membrane and Conventional Chemical Extractions 被引量:3
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作者 LIUZHAOHUI J.SCHOENAU 《Pedosphere》 SCIE CAS CSCD 1999年第1期91-96,共6页
Four testing methods using canon exchange membrane (CEM), ammonium acetate, ASI (0.25 mol L-1 NaHCO3+0.01 mol L-1 EDTA +0.01 mol L-1 NH4P) and 1.0 mol L-1 boiling nitric acid, respectively, were used to evaluate soil ... Four testing methods using canon exchange membrane (CEM), ammonium acetate, ASI (0.25 mol L-1 NaHCO3+0.01 mol L-1 EDTA +0.01 mol L-1 NH4P) and 1.0 mol L-1 boiling nitric acid, respectively, were used to evaluate soil available K. The soil K tested by CEM was significantly correlated with that by the other (conventional) methods (r2=0.43**~0.95***). The soil K tested by CEM saturated with NH4HCO3 (15 min extraction) was most closely correlated with that by the other methods (2 =0. 60***~0.95***). Potassium availability, as predicted by soil test, was comparable to actual K uptake by canola and wheat grown on the soils in growth chamber. Regression analyses showed that plant K uptake was more closely correlated with K extracted by CEM (r2=0.56***~0.81***) than that by the conventional methods (r2=0.46***~;0.81***), most closely correlsted with that by NH4HCO3-saturated CEM for 15 min (r2=0.81***), and worst correlated with that by HNO3 (r2=0.45**~0.72***). 展开更多
关键词 canon exchange resin membrane conventional chemical extractions soil available potassium
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Effect of Chemical Extraction on Physicochemical and Mechanical Properties of Doum Palm Fibres 被引量:3
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作者 S. Zannen L. Ghali +1 位作者 M. T. Halimi M. Ben Hssen 《Advances in Materials Physics and Chemistry》 2014年第10期203-216,共14页
The aim of this study is to investigate the effect of chemical extraction method on the properties of doum palm fibres. The method of extraction which is carried out is a soda treatment. First, an investigation of the... The aim of this study is to investigate the effect of chemical extraction method on the properties of doum palm fibres. The method of extraction which is carried out is a soda treatment. First, an investigation of the extraction processes was undertaken. Secondly, the physical properties (surface morphology, density, linear density and diameter), the mechanical properties (tenacity, strain) and chemical properties (FT-IR spectra) of doum palm fibres were inspected. Finally, a comparison between properties of doum palm fibres and other vegetal ones has been included. Results indicates an influence of soda treatment on properties of Doum palm fibers. In fact, there is an improvement on fibers diameter and linear density while increasing soda concentration, temperature and treatment duration. Moreover, the studied fibers have a low density which does not exceed 1. The fibers tenacity achieved the maximum value of 20.86 cN/Tex when precessing in the following combination (0.75 N, 100°C and 180 mn). In the end, the FTIR spectra reveals a change in structure after this alkali treatment while increasing the cellulose amount exposed on the fiber surface and consequently the number of possible reaction sites (OH groups). 展开更多
关键词 Doum PALM Fibres Leaf SHEATH extraction SODA Treatment Physical PROPERTIES MECHANICAL PROPERTIES chemical PROPERTIES
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Ionic liquid-based salting-out extraction of bio-chemicals 被引量:1
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作者 Jianying Dai Yaqin Sun Zhilong Xiu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第2期185-193,共9页
Ionic liquids(ILs)are known as green solvents,and have been widely used in the dissolution and transformation of biopolymers,the extraction of bioactive compounds and metal ions,and the capture of SO2 or CO2.However,l... Ionic liquids(ILs)are known as green solvents,and have been widely used in the dissolution and transformation of biopolymers,the extraction of bioactive compounds and metal ions,and the capture of SO2 or CO2.However,less attention was given to the separation of bio-based chemicals,such as diols and organic acids.Bio-based chemicals can be efficiently separated by organic solvent-based salting-out extraction(SOE)from fermentation broths,while organic solvents are normally unfriendly to environment and process safety in commercialized production due to their toxicity or/and flammability.In recent years,the IL-based SOE system has been explored in the separation of bio-based chemicals as an alternative of organic solvent-based SOE system.In this review,the progress of IL-based SOE of biobased chemicals has been summarized,including the effect of ILs structure on the formation of aqueous two phases,and the influences of ILs structure and concentration,temperature and pH on the partition behaviors of target products and ILs as well as removal of impurities.Most of bio-based chemicals could be distributed into the IL-rich phase with high recovery,while the partition behaviors of bio-based chemicals are sometimes different from that in organic solvent-based SOE systems.Although the results of ILbased SOE are promising,further studies are still required in the increased selectivity of target products over by-products,recovery and recycling of ILs,and the separation between ILs and bio-based chemicals.Additionally,three kinds of integrated bioprocesses would be developed on basis of utilization of ILs as extractant for SOE,catalyst for condensation reaction and solvent for pretreatment of lignocellulose. 展开更多
关键词 Downstream processing BIOSEPARATION Ionic liquids Salting-out extraction Partition behavior Bio-based chemicals
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Research Progress on Chemical Constituents,Extraction Methods and Pharmacological Effects of Sauropus spatulifolius Beille 被引量:1
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作者 Xin XIE Liyuan LI +8 位作者 Chunxiao QIN Tong LI Yajie JING Suoyi HUANG Weijia LIN Xiaolin FU Liqiong ZHOU Huiqin LI Cuixia WANG 《Medicinal Plant》 CAS 2022年第6期105-108,共4页
Sauropus spatulifolius Beille is a small evergreen shrub in Sauropus of the Euphorbiaceae family.It mainly contains chemical components such as amino acids,proteins,carbohydrates,polypeptides,glycosides,saponins,tanni... Sauropus spatulifolius Beille is a small evergreen shrub in Sauropus of the Euphorbiaceae family.It mainly contains chemical components such as amino acids,proteins,carbohydrates,polypeptides,glycosides,saponins,tannins,organic acids,alkaloids,coumarin and lactones,volatile oils and oils.In addition,the chemical components obtained by different extraction processes are also different.S.spatulifolius Beille mainly has antitussive and expectorant,anti-inflammatory and analgesic,bacteriostatic,antioxidant,and anti-allergic effects.The rich biological activity of S.spatulifolius Beille makes it have clinical applications such as adjuvant treatment of pulmonary edema,recovery of lung function,and treatment of chronic laryngitis or chronic pharyngitis.In this paper,the main chemical components,extraction and identification methods and biological activity of S.spatulifolius Beille were described in depth,in order to further lay a solid foundation for the in-depth research,development and utilization of S.spatulifolius Beille. 展开更多
关键词 Sauropus spatulifolius Beille chemical constituents extract Pharmacological effects
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Optimization of Response Surface of Ultrasonic-assisted Extraction of Rizhao Black Tea 被引量:1
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作者 TANG Yu-huan LIANG Qing +2 位作者 ZOU Jia-jia DING Xin DING Li-xiao 《Chinese Food Science》 2012年第3期35-38,共4页
[ Objectivel The aim was to determine the optimal technology for ultrasonic-assisted extraction of black tea was determined. [ Methed] Taking Black Tea as materials, the Box-Behnken response surface design method of t... [ Objectivel The aim was to determine the optimal technology for ultrasonic-assisted extraction of black tea was determined. [ Methed] Taking Black Tea as materials, the Box-Behnken response surface design method of tea polyphenols ultrasonic-assisted extraction process optimi- zation was applied. The regression optimization model of the ethanol volume fraction, ultrasonic time, and ultrasonic temperature, ethyl acetate extract stalling time and tea polyphenols was established. [ Result] The influence of four factors on the black tea polyphenol solvents affecting size was as follows: ultrasonic time 〉 ethanol volume fraction 〉 stalling extraction time 〉 ultrasound temperature. The best extraction process was ultrasonic time 80 min, volume fraction of 88.99% ethanol, extraction time 89.97 min, ultrasonic temperature of 80℃. At the optimized technical parameters, the black tea phenolic extraction yield can be as high as 73.50%. [ Conclusion] The study provided theoretical basis for the development of tea leaves and black tea. 展开更多
关键词 Rizhao black tea ultrasonic-assisted extraction extraction yield Response surface China
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Chemical Extraction Preparation of Delithiated Cathode Materials of Li-ion Battery
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作者 闫时建 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第6期863-866,共4页
A method of conventional chemical reaction to prepare delithiated cathode materials of Li-ion battery was introduced. The cathode material of Li-ion battery was mixed with oxidizing agent Na2S2O8 in water solution, an... A method of conventional chemical reaction to prepare delithiated cathode materials of Li-ion battery was introduced. The cathode material of Li-ion battery was mixed with oxidizing agent Na2S2O8 in water solution, and the solution was stirred continuously to make the chemical reaction proceed sufficiently, then the reaction product was filtered and finally the insoluble delithiated cathode material was obtained. A series of tests were conducted to verify the composition, crystal structure and electrochemical property of the delithiated cathode materials were all desirable. This method overcomes the shortcomings of battery charging preparation and chemical extraction preparation employing other oxidizing agents. 展开更多
关键词 chemical extraction delithiated cathode material Li-ion battery
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Mathematical modeling for of arctigenin from acidultrasonic-assisted extractionhydrolyzed FructusArctii
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作者 Dai Lin Zhang Yong +2 位作者 Hu Chi Qian Hongliang Wang Zhixiang 《Journal of Southeast University(English Edition)》 EI CAS 2017年第3期362-369,共8页
A mathematical model based on Fick's first lawwas established to describe the process of ultrasonic-assisted extraction of arctigenin from acid hydrolyzed FructusArctii.Acid hydrolization with hydrochloric acid pr... A mathematical model based on Fick's first lawwas established to describe the process of ultrasonic-assisted extraction of arctigenin from acid hydrolyzed FructusArctii.Acid hydrolization with hydrochloric acid promotes the conversion of arctiin to arctigenin in the arctiin-rich active pharmaceutical ingredient, and the hydrolyzed products were further examined to investigate the process setup. By considering the mechanism of the extraction process and experimental data, the effects of parameters including solven to solid ratio, particle size of hydrolyzed samples, ethano volume fraction, ultrasound power, extraction temperature and extraction time on concentration of arctigenin were analyzed in detail. The model was suitable for simulating the process of ultrasonic-assisted extraction of arctigenin. The simulation results of the model agree well with experimental data with the deviation below13%, indicating that the mathematical mode can provide valuable guidance for the extraction of arctigenin from acid hydrolyzed FructusArctii. 展开更多
关键词 FructusArctii acid hydrolysis ultrasonic-assisted extraction ARCTIGENIN mathematical model
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Research Progress of Extraction Technology and Application of Chemical Substances in Perilla Seed
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作者 Shi Yilin Gu Xianhong +1 位作者 Mao Wei Wang Zhanbin 《Animal Husbandry and Feed Science》 CAS 2016年第2期113-118,共6页
Perilla seed is one of the traditional Chinese herbs normally used both as food and medicine for its various functional ingrediems such as protein, amino acids, ct-linolenic acid, flavones, rosmarinic acid, terpenes, ... Perilla seed is one of the traditional Chinese herbs normally used both as food and medicine for its various functional ingrediems such as protein, amino acids, ct-linolenic acid, flavones, rosmarinic acid, terpenes, polysaccharides, etc.. Pefilla seed is with physiological features in slowing down decrepitude, lower- ing blood pressure, cholesterol, inhibiting cancer cell differentiation, and improving body immune. The present paper summarized research progress at home and abroad on chemical component analysis, extraction technology and application status of perilla seed in the fields of feed, health care, food and chemical industry in recent years, in order to provide a reference basis for reasonable development of perilla seed. 展开更多
关键词 Perilla seed chemical components extraction technology APPLICATION
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EVALUATION OF GEOCHEMICAL QUALITY CONTROLIN DETERMINATION OF Mn IN SOILS USING A SEQUENTIAL CHEMICAL EXTRACTION
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作者 DONG De ming, FANG Chun sheng, ZHAO Wen jin, XIE Zhong lei(College of Environment and Resource, Jilin University, Changchun 130023, P.R. China) 《Chinese Geographical Science》 SCIE CSCD 2002年第2期166-170,共5页
Sequential chemical extraction procedure has been widely used to partition particulate trace metals into various fractions and to describe the distribution and the statue of trace metals in geo environment. One sequen... Sequential chemical extraction procedure has been widely used to partition particulate trace metals into various fractions and to describe the distribution and the statue of trace metals in geo environment. One sequential chemical extraction procedure was employed here to partition various fractions of Mn in soils. The experiment was designed with quality controlling concept in order to show sampling and analytical error. Experimental results obtained on duplicate analysis of all soil samples demonstrated that the precision was less than 10%(at 95%confidence level). The accuracy was estimated by comparing the accepted total concentration of Mn in standard reference materials (SRMs) with the measured sum of the individual fractions. The recovery of Mn from SRM1 and SRM2 was 94.1%and 98.4%, respectively. The detection limit, accuracy and precision of the sequential chemical extraction procedure were discussed in detailed. All the results suggest that the trueness of the analytical method is satisfactory. 展开更多
关键词 FRACTION sequential chemical extraction quality control
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Adenosine cyclic phosphate with ultrasonic-assisted pectinase extraction alleviated allergic reactions in RBL-2H3 through inhibiting the influx of intracellular Ca^(2+)
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作者 Qiao Bai Xiaoping Feng +5 位作者 Yu Wang Chunyu Wu Ye Liu Jiao Sun Tianli Yue Fangyu Long 《Food Science and Human Wellness》 SCIE CSCD 2023年第3期832-841,共10页
Jujube contains abundant cyclic adenosine monophosphate(cAMP)and the ultrasonic-assisted pectinase extraction(UAPE)conditions for obtaining the maximum cAMP yield from jujube were optimized.Orthogonal array design was... Jujube contains abundant cyclic adenosine monophosphate(cAMP)and the ultrasonic-assisted pectinase extraction(UAPE)conditions for obtaining the maximum cAMP yield from jujube were optimized.Orthogonal array design was applied to evaluate the effects of 4 variables by UAPE on cAMP yield.The results showed that the optimal cAMP yield(783.0μg/g)was derived at ratio of liquid to solid 5 mL/g,ratio of pectinase to raw material 1.5%,time 60 min and temperature 40℃.Moreover,the effect of cAMP on the anti-allergic function of action induced by immunoglobulin E(IgE)and its meschanism was investigated through establishing the sensitized cell model in rat basophilic leukemia(RBL-2 H3)cells using dinitrophenylated(DNP)-bovine serum albumin(BSA)-IgE.The results showed that cAMP interfered with sensitized cells,effectively inhibited the occurrence of basophil degranulation in dose dependence,and significantly reduced the activity ofβ-hexosamindase(β-hex),at the optimal concentration of 50μg/mL.The level of anti-inflammatory factor interleukin-10(IL-10)was promoted and the content of pro-inflammatory factor tumor necrosis factor-α(TNF-α)was suppressed by cAMP.In addition,influx of intracellular Ca^(2+) was repressed effectively.Our results demonstrate that jujube cAMP regulated the cytokine balance in the allergy pathway through blocking the influx of extracellular Ca^(2+),with the prevention of allergy symptoms. 展开更多
关键词 ultrasonic-assisted pectinase extraction Cyclic adenosine monophosphate Rat basophilic leukemia cells Ca^(2+)influx Allergy
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Traditional Pathway of Oil Extraction from <i>Quassia undulate</i>Seeds and Its Chemical Characteristic 被引量:1
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作者 Ndiaye Seyni Gueye Mathieu +2 位作者 Baldé Samba Ndiaye Bou Ayessou Nicolas Cyrille 《Food and Nutrition Sciences》 2021年第5期452-461,共10页
In Africa, traditional vegetable oil extraction often involves the use of plants in the manufacturing process. <span style="font-family:Verdana;"><span style="font-family:Verdana;"><... In Africa, traditional vegetable oil extraction often involves the use of plants in the manufacturing process. <span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Quassia undulate</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> oil is thus traditionally prepared. An expedition went to Kédougo (a region in southeastern Senegal involving women of the Bassaris community) in June 2018 to study the </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Q</span></i></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">.</span><i><span style="font-family:Verdana;"> undulate</span></i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> oil traditional extraction mode. Thus, the objective of this study is to follow the traditional extraction of </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Q</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span><span><span><i><span style="font-family:;" "=""> </span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">undulate</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> oil and to perform the physico-chemical analysis of the obtained oil. Oil samples taken after the survey allowed the oil physico-chemical characterization. The traditional oil extraction made by four women from Eganga, Ethiolo, and Ebarack’s villages reveals oil clear that is solid at room temperature. The study of the established chart revealed the use of </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Pilliostigma</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> <i>thonnintigi</i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> leaves during the oil preparation. The oil shows characteristics comparable to shea butter, and the oil stability can be compared to the corn and peanut oil one. The physicochemical analysis showed oil solid at room temperature with an acid value between </span><span style="font-family:Verdana;">1.223 ± 0.013 and 7.333 ± 0.465. The saponification value was between</span><span style="font-family:Verdana;"> 190.489 ± 3.083 and 199.732 ± 3.107, and the peroxide value between 4.453 ± 0.042 and 8.644 ± 0.285. The iodine value</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> were between 21.455 ± 2.440 and 38.068 ± 0.082, and the refractive index 1.462 - 1.463. </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Q</span></i></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">.</span><i><span style="font-family:Verdana;"> undulate</span></i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> oil offers several technological perspectives. However, it would be interesting to study the impact of </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">P</span></i></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">.</span><i><span style="font-family:Verdana;"> thonnintigi</span></i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> leaves during extraction. The fatty acid profile should also be determined.</span></span></span> 展开更多
关键词 Quassia undulate Traditional extraction Physico-chemical Characterization
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