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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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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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Ultrasonic-Assisted Extraction of Fucoxanthin from Marine Macroalga Padina australis:Optimization,Bioactivity,and Structural Characterization
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作者 L.Antony Catherine Flora Kirubanandan Shanmugam Renganathan Sahadevan 《Proceedings of Anticancer Research》 2024年第5期89-104,共16页
Macroalgae serve as a potential feedstock for fucoxanthin extraction.Fucoxanthin,a bioactive pigment found in the chloroplasts of marine algae,exhibits significant pharmacological properties.As a member of the caroten... Macroalgae serve as a potential feedstock for fucoxanthin extraction.Fucoxanthin,a bioactive pigment found in the chloroplasts of marine algae,exhibits significant pharmacological properties.As a member of the carotenoid family,fucoxanthin plays a crucial role in both the food and pharmaceutical industries.This research explores the effects of ultrasonics on the extraction of fucoxanthin from the marine macroalga Padina australis.In addition,various extraction techniques and the influence of solvents on the efficient separation of fucoxanthin from algae have been studied and compared.Using methanol,chloroform,and a combination of methanol and chloroform(1:1,v/v),conventional fucoxanthin extraction from Padina australis yielded 8.12 mg of fucoxanthin per gram of biomass.However,the ultrasonic-assisted extraction resulted in a significantly higher yield of 16.9 mg of fucoxanthin per gram of biomass,demonstrating that the use of ultrasonics enhances the extraction rate compared to conventional methods.Therefore,the efficient separation of fucoxanthin from Padina australis is highly dependent on ultrasonic-assisted extraction.The process conditions for the extraction were optimized to maximize the yield of fucoxanthin from seaweeds.The following parameters were selected for optimization studies:moisture content,particle size,mixing speed,extraction temperature,extraction duration,and solid-to-solvent ratio.The extracted fucoxanthin exhibited various biological activities,including antimicrobial and antioxidant properties,and its structure was elucidated through FTIR and NMR spectroscopy.Additionally,thin-layer chromatography of the crude algae extracts confirmed the presence of fucoxanthin in the marine algae.Given these findings,the optimized extraction process holds the potential for scaling up to large-scale fucoxanthin production.Fucoxanthin,as a potent pharmacological agent,offers promising applications in the treatment of various ailments. 展开更多
关键词 Marine algae FUCOXANTHIN ULTRASONICS extraction OPTIMIZATION TLC DPPH Antimicrobial antioxidant activities
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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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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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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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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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An experimental study exploring the influencing factors for ultrasonic-assisted extraction of flavonoid compounds from leaves of Amorpha fruticosa L. 被引量:15
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作者 Jingyao Tian Siddique Muhammad +5 位作者 Ai Chen Peng Chen Jinghong Wang Chengwu Yang Hui Yuan Zhensheng Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第5期1735-1741,共7页
In this paper,the ultrasonic-assisted extraction process of flavonoid compounds from leaves of Amorpha fruticosa is optimized.In single factor experiments,solid/liquid ratios,ultrasonic power,ethanol concentrations an... In this paper,the ultrasonic-assisted extraction process of flavonoid compounds from leaves of Amorpha fruticosa is optimized.In single factor experiments,solid/liquid ratios,ultrasonic power,ethanol concentrations and extraction cycles were experimental factors.Box–Behnken central composite design and RSM analyzed the effects of the four factors on the yield of total flavonoids.The optimal extraction parameters were solid/liquid ratio 1:50 g/mL,ultrasonic power 316 W,ethanol concentration 50%,4 extraction cycles.In the optimized condition,the estimated value of the regression model was 66.6456 mg/g while the measured value was 66.4329 mg/g. 展开更多
关键词 Amorpha fruticosa L. Flavonoid COMPOUNDS ULTRASONIC extractION Response surface METHODOLOGY
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Evaluating the performances of accelerated-solvent extraction, microwave-assisted extraction, and ultrasonic-assisted extraction for determining PCBs, HCHs and DDTs in sediments 被引量:1
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作者 张蓬 葛林科 +1 位作者 周传光 姚子伟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第5期1103-1112,共10页
Three extraction techniques have been recently used for the quantitative extraction of semi-volatile organic pollutants in sediments, i.e. accelerated solvent extraction (ASE), microwave assisted extraction (MAE) ... Three extraction techniques have been recently used for the quantitative extraction of semi-volatile organic pollutants in sediments, i.e. accelerated solvent extraction (ASE), microwave assisted extraction (MAE) and ultrasonic assisted extraction (UAE). However, their extraction efficiencies have rarely been quantitatively compared using rigorous mathematical methods. In this paper, one-way analysis of variance (ANOVA) was employed to evaluate the performance of ASE, MAE and UAE in the overall extraction of PCBs, DDTs and HCHs by analysis of their recoveries from the Standard Reference Material IAEA-417, a sediment sample certified by many international laboratories. Conclusions were drawn at a significance level of P〈 0.05. No significant differences were found among the mean values for method recoveries using ASE, MAE and UAE. The mean values for real recoveries using ASE and MAE were nearly identical, but the real recovery using UAE was much lower. The concentrations of all PCBs, DDTs and HCHs except for CB52 and o,p'-DDT using UAE were the lowest. Comparing the results obtained using ASE with MAE, the concentrations of CB28, CB52, CB138, ct-HCH, [3-HCH, p,p'-DDE and p,p'-DDD were nearly identical, while the concentrations of other compounds were significantly different. Based on the low recoveries, it was concluded that UAE is a relatively inefficient extraction method, while ASE and MAE are equivalent methods. Taking into consideration the relative standard deviation (RSD) values, solvent volume, extraction time, and purchasing costs of the apparatus, MAE was considered superior to ASE for extraction of PCBs, DDTs and HCHs. 展开更多
关键词 extraction technique sediment PCB HCH DDT
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Optimization of the Ultrasonic-assisted Extraction Process for Total Flavonoids in Primula sikkimensis Hook.by Response Surface Methodology 被引量:1
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作者 Qing XIA Dandan TANG +1 位作者 Zhiqiang ZHANG Jianhui JIANG 《Medicinal Plant》 CAS 2021年第1期35-39,共5页
[Objectives]To optimize the ultrasonic-assisted extraction process for total flavonoids in Primula sikkimensis Hook.[Methods]The effects of ethanol volume fraction,extraction time,extraction temperature,ultrasonic tim... [Objectives]To optimize the ultrasonic-assisted extraction process for total flavonoids in Primula sikkimensis Hook.[Methods]The effects of ethanol volume fraction,extraction time,extraction temperature,ultrasonic time and solid-to-liquid ratio on the yield of total flavonoids were investigated by single factor method,and the extraction process for total flavonoids in P.sikkimensis was optimized by Box-Behnken experimental design.[Results]The optimal extraction process for total flavonoids in P.sikkimensis was ethanol volume fraction 45%,extraction time 29 min,extraction temperature 80℃,solid-to-liquid 1∶40(g/mL)and ultrasonic time 10 min.Under such conditions,the average yield of total flavonoids in P.sikkimensis was 3.09%.[Conclusions]The optimized extraction process is simple and feasible,and is expected to provide a reference for the extraction of total flavonoids in P.sikkimensis. 展开更多
关键词 Primula sikkimensis Hook. Total flavonoids Response surface methodology(RSM) extraction process
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Optimization of Ultrasonic-assisted Extraction of Polysaccharide from Hibiscus syriacus L.
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作者 Haibo DENG Bei NING +3 位作者 Shunfan ZHU Chenzhong JIN Yihong HU Xuejiao ZHANG 《Agricultural Biotechnology》 CAS 2018年第3期161-164,共4页
The ultrasonic-assisted extraction of polysaccharides from Hibiscus syriacus L. at 180 W low power was optimized by the single factor tests and orthogonal test. Extraction temperature,ultrasonic treatment time,extract... The ultrasonic-assisted extraction of polysaccharides from Hibiscus syriacus L. at 180 W low power was optimized by the single factor tests and orthogonal test. Extraction temperature,ultrasonic treatment time,extraction times,and material-to-liquid ratio were considered as independent variables. The results suggested that the best extraction condition were determined as the extraction temperature at 80 ℃,the ultrasonic treatment time of 40 min,the material-to-liquid ratio at1∶ 20( g/ml),and the extraction times of 3. Under the optimal conditions,the extraction rate of polysaccharides from Hibiscus syriacus was 3. 114%. 展开更多
关键词 Hibiscus syriacus L. POLYSACCHARIDE Ultrasound-assisted extraction
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In-situ Si particle-reinforced joints of hypereutectic Al−60Si alloys by ultrasonic-assisted soldering
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作者 Yuan-xing LI Xiang-bo ZHENG +3 位作者 Chao-zheng ZHAO Zong-tao ZHU Yu-jie BAI Hui CHEN 《中国有色金属学报》 北大核心 2025年第1期77-90,共14页
To improve the wettability of hypereutectic Al−60Si alloy and enhance the mechanical properties of the joints,Al−60Si alloy was joined by ultrasonic soldering with Sn-9Zn solder,and a sound joint with in-situ Si parti... To improve the wettability of hypereutectic Al−60Si alloy and enhance the mechanical properties of the joints,Al−60Si alloy was joined by ultrasonic soldering with Sn-9Zn solder,and a sound joint with in-situ Si particle reinforcement was obtained.The oxide film of Al−60Si alloy at the interface was identified by transmission electron microscopy(TEM)analysis as amorphous Al_(2)O_(3).The oxide of Si particles in the base metal was also alumina.The oxide film of Al−60Si alloy was observed to be removed by ultrasonic vibration instead of holding treatment.Si particle-reinforced joints(35.7 vol.%)were obtained by increasing the ultrasonication time.The maximum shear strength peaked at 99.5 MPa for soldering at 330℃with an ultrasonic vibration time of 50 s.A model of forming of Si particles reinforced joint under the ultrasound was proposed,and ultrasonic vibration was considered to promote the dissolution of Al and migration of Si particles. 展开更多
关键词 hypereutectic Al−60Si alloy ultrasonic-assisted soldering Si particle reinforcement Sn−9Zn solder
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Determination of Lignans in Schisandra sphenanthera and Schisandra chinensis Using Ionic Liquid-based Ultrasonic-assisted Extraction and High-performance Liquid Chromatography 被引量:1
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作者 GUAN Lianyue LUO Qiang +1 位作者 LIANG Na YU Wei 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2018年第6期887-892,共6页
A green, rapid and precise sample pretreatment technique, IL-based UAE(ionic liquid-based ultrasonic- assisted extraction), was coupled with high-performance liquid chromatographic separation to identify the main ef... A green, rapid and precise sample pretreatment technique, IL-based UAE(ionic liquid-based ultrasonic- assisted extraction), was coupled with high-performance liquid chromatographic separation to identify the main effective components in Schisandra sphenanthera(S, sphenanthera) and Schisandra chinensis(S, ehinensis) including schisantherin A, schisandrin A, and deoxyschizandrin. Four different types of ionic liquids have been investigated, finally [C6MIM][BF4] was used as the extraction solvent. A powder form of S. sphenanthera and S. chinensis was mixed with the [C6MIM][BF4] to produce a suspension. This suspension was ultrasonically extracted in a water bath at room temperature. Several of the process parameters were optimized, including the type of ionic liquid used and its volume, the sample amount, the size of the sample particle, the extraction time, etc. HPLC calibration curves were estab-lished for all the analytes and proved to be linear(r〉0.9999). The lowest detection level for schisandrin A was 0.12μg/mL, for schisantherin A was 0.08 μg/mL, and for deoxyschizandfin was 0.10μg/mL. The recoveries of the target compounds were from 74.19% to 109.33%. The standard deviations for detection were generally no more than 6.31%. In contrast to conventional extraction methods, the IL-based UAE did not involve volatile organic volatile solvents, and the analysis time, required sample and solvent vohtrnes were also lower than those of the conventional techniques. 展开更多
关键词 Ionic liquid High-performance liquid chromatography ultrasonic-assisted extraction Effective constituent
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Rapid determination of volatile constituents in safflower from Xinjiang and Henan by ultrasonic-assisted solvent extraction and GC-MS 被引量:3
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作者 Ling-Han Jia Yi Liu Yu-Zhen Li 《Journal of Pharmaceutical Analysis》 SCIE CAS 2011年第3期213-218,共6页
The total volatile components were extracted from safflower by ultrasonic-assisted solvent extraction (USE) and their chemical constituents were analyzed by gas chromatographymass spectrometry (GC-MS) to provide s... The total volatile components were extracted from safflower by ultrasonic-assisted solvent extraction (USE) and their chemical constituents were analyzed by gas chromatographymass spectrometry (GC-MS) to provide scientific basis for the quality control of safflower. Five different solvents (diethyl ether, ethanol, ethyl acetate, dichloromethane and acetone) were used and compared in terms of number of volatile components extracted and the peak areas of these components in TIC. The results showed that USE could be used as an efficient and rapid method for extracting the volatile components from safflower. It also could be found that the number of components in the TIC of ethyl acetate extract was more than that in the TIC of other solvent ones. Meanwhile, the volatile components of safflower from Xinjiang Autonomous Region and Henan Province of China were different in chemical components and relative contents. It could be concluded that both the extraction solvents and geographical origin of safflower are responsible for these differences. The experimental results also indicated that USE/GC-MS is a simple, rapid and effective method to analyze the volatile oil components of safflower. 展开更多
关键词 SAFFLOWER Ultrasonic solvent extraction Gas chromatographymass spectrometry (GC-MS)
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Preventing formation of intermetallic compounds in ultrasonic-assisted Sn soldering of Mg/Al alloys through pre-plating a Ni coating layer on the Mg substrate
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作者 Yingzong Liu Yuanxing Li +1 位作者 Hui Chen Zongtao Zhu 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期726-741,共16页
Magnesium and aluminum alloys are widely used in various industries because of their excellent properties,and their reliable connection may increase application of materials.Intermetallic compounds(IMCs)affect the joi... Magnesium and aluminum alloys are widely used in various industries because of their excellent properties,and their reliable connection may increase application of materials.Intermetallic compounds(IMCs)affect the joint performance of Mg/Al.In this study,AZ31 Mg alloy with/without a nickel(Ni)coating layer and 6061 Al alloy were joined by ultrasonic-assisted soldering with Sn-3.0Ag-0.5Cu(SAC)filler.The effects of the Ni coating layer on the microstructure and mechanical properties of Mg/Al joints were systematically investigated.The Ni coating layer had a significant effect on formation of the Mg_(2)Sn IMC and the mechanical properties of Mg/Al joints.The blocky Mg_(2)Sn IMC formed in the Mg/SAC/Al joints without a Ni coating layer.The content of the Mg_(2)Sn IMC increased with increasing soldering temperature,but the joint strength decreased.The joint without a Ni coating layer fractured at the blocky Mg_(2)Sn IMC in the solder,and the maximum shear strength was 32.2 MPa.By pre-plating Ni on the Mg substrate,formation of the blocky Mg_(2)Sn IMC was inhibited in the soldering temperature range 240–280℃and the joint strength increased.However,when the soldering temperature increased to 310℃,the blocky Mg_(2)Sn IMC precipitated again in the solder.Transmission electron microscopy showed that some nano-sized Mg_(2)Sn IMC and the(Cu,Ni)_(6)Sn_(5)phase formed in the Mg(Ni)/SAC/Al joint soldered at 280℃,indicating that the Ni coating layer could no longer prevent diffusion of Mg into the solder when the soldering temperature was higher than 280℃.The maximum shear strength of the Mg(Ni)/SAC/Al joint was 58.2 MPa for a soldering temperature of 280℃,which was 80.7%higher than that of the Mg/SAC/Al joint,and the joint was broken at the Mg(Ni)/SAC interface.Pre-plating Ni is a feasible way to inhibit formation of IMCs when joining dissimilar metals. 展开更多
关键词 ultrasonic-assisted soldering Mg_(2)Sn Ni coating layer Shear strength
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Extraction of copper from copper-bearing biotite by ultrasonic-assisted leaching 被引量:2
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作者 Baoqiang Yu Jue Kou +1 位作者 Chunbao Sun Yi Xing 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第2期212-217,共6页
Copper-bearing biotite is a refractory copper mineral found on the surface of the Zambian Copperbelt.Biotite is a copper oxide from which copper is extracted by various methods,especially by leaching.Leaching is the p... Copper-bearing biotite is a refractory copper mineral found on the surface of the Zambian Copperbelt.Biotite is a copper oxide from which copper is extracted by various methods,especially by leaching.Leaching is the process of extracting a substance from a solid material dissolved in a liquid.To improve the efficiency of the leaching process by a more effective method,a new method called ultrasonic-assisted acid leaching is proposed and applied in this study.Compared with regular acid leaching,the ultrasound method reduced the leaching time from 120 to 40 min,and sulfuric acid concentration reduced from 0.5 to 0.3 mol·L^(-1).Besides,leaching temperature could be reduced from 75 to 45°C at the leaching rate of 78%.The mechanism analysis indicates that an ultrasonic wave can cause the delamination of a copper-bearing biotite and increase its specific surface area from 0.55 to 1.67 m^(2)·g^(-1).The results indicate that copper extraction from copper-bearing biotite by ultrasonic-assisted acid leaching is more effective than regular acid leaching.This study proposes a promising method for recycling valuable metals from phyllosilicate minerals. 展开更多
关键词 ultrasonic wave copper extraction DELAMINATION copper-bearing biotite
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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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Preparation of silver nanoparticles through the reduction of straw-extracted lignin and its antibacterial hydrogel
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作者 Lou Zhang Shuo Li +4 位作者 Fu Tang Jingkai Zhang Yuetong Kang Hean Zhang Lidong Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期504-514,共11页
Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are... Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water pollution.In this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing agent.Experimental analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag NPs.The surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their aggregation.After the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite hydrogel.The inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag NPs.The prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings. 展开更多
关键词 silver nanoparticles HYDROGEL STRAW extraction ANTIBACTERIAL
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Fractionation and characterization of thermal extracts from lignite under ultrasonic-assisted extraction 被引量:1
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作者 Xin Zha Shibiao Ren +7 位作者 Tao Jiang Jingchong Yan Zhicai Wang Zhiping Lei Chunxiu Pan Shigang Kang Zhanku Li Hengfu Shui 《Carbon Resources Conversion》 2021年第1期214-218,共5页
Hypercoal(HPC)is promising feedstock for producing coal-based chemicals due to its extremely low ash content and high reactivity.However,the conventional methods for HPC preparation through thermal extraction under me... Hypercoal(HPC)is promising feedstock for producing coal-based chemicals due to its extremely low ash content and high reactivity.However,the conventional methods for HPC preparation through thermal extraction under mechanical stirring are difficult to scale-up due to the low HPC yield and large consumption of solvent.This work conducted ultrasonic-assisted extraction(UAE)instead of mechanical stirring to enhance the efficiency of HPC production,and the effect of technological conditions on the HPC yield were examined.It was found that the UAE could remarkably enhance the HPC yield from 52.3%to 82.4%.Moreover,the ratio of soluble(HPC-S)to deposit(HPC-D)increased from 1.65 to 2.85,verifying the high efficiency and the capacity of altering the product distribution of UAE. 展开更多
关键词 Hypercoal UAE Thermal extracts Product distribution
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Optimization of ultrasonic-assisted enzymatic extraction of flavonoids from the fruit oiAronia melanocarpa
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作者 Yan Wang Ming Song +1 位作者 Wei Xu Weizhuo Xu 《Journal of Polyphenols》 2021年第1期76-83,共8页
As a new resource food,Aronia melanocarpa is rich in flavonoids,which has a broad development prospect.In order to obtain a higher extraction rate of flavonoids,cellulase was used to extract total flavonoids from the ... As a new resource food,Aronia melanocarpa is rich in flavonoids,which has a broad development prospect.In order to obtain a higher extraction rate of flavonoids,cellulase was used to extract total flavonoids from the fruits of Aronia melanocarpa by ultrasonic-assisted enzymatic extraction(UAEE).The extraction process was optimized by single factor experiment and orthogonal experiment.The optimum conditions were as follows:enzymatic hydrolysis time 2.0 h,enzymatic hydrolysis temperature 37℃,enzyme content 0.5%(by weight of fruit pulp),ethanol concentration 90%,solid-liquid ratio 1:20,enzymatic hydrolysis temperature 37℃,enzymatic hydrolysis temperature 37℃,enzyme content 0.5%(by weight of fruit pulp),ethanol concentration 90%.Ultrasonic extraction time 1,0h,temperature 45℃.Under the above conditions,the extraction yield of flavonoids reached 1.455 mg/g.Compared with ultrasonic-assisted extraction(UAE),the extraction yield was significantly improved.Therefore,ultrasonic-assisted enzymatic hydrolysis is an effective method for the extraction of total flavonoids hom Aronia melanocarpa. 展开更多
关键词 Aronia melanocarpa CELLULASE ultrasonic-assisted
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