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Study on Extraction of Oolong Tea Assisted by Ultrasonic Wave and 4C Technique and Its Application
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作者 Guofeng YU Cuishu LENG +9 位作者 Keli FANG Zhiguang LIU Jianhong SUN Zengyu Wang Xuegang LI Shuai Zhang Jian LIU Xulun WEI Qiulin LIU Shoujie NIE 《Agricultural Biotechnology》 2024年第3期24-27,共4页
[Objectives]The extraction conditions of formula oolong tea were investigated by an orthogonal experiment.[Methods]The technical conditions were optimized by the 4C method,and the application of formula oolong tea ext... [Objectives]The extraction conditions of formula oolong tea were investigated by an orthogonal experiment.[Methods]The technical conditions were optimized by the 4C method,and the application of formula oolong tea extract in cigarettes was studied.[Results]①In the experimental range,the best sensory evaluation effect of formula oolong tea extract was obtained with extraction conditions of 70%ethanol as extraction solvent,extraction time h,extraction temperature 25℃,and ultrasonic frequency 80 kHz,and follow-up low-temperature concentration,low-temperature sedimentation and low-temperature centrifugation.②The effects of different centrifugal speeds on the quality of formula oolong tea extract were explored.The formula oolong tea extract obtained under the conditions of 3000 r/min and centrifugal time of 10 min showed the best evaluation effect with soft and delicate smoke,rich smoke fragrance,good comfort and refreshing mouthfeel.③The effective aroma components in the formula oolong tea extract were qualitatively analyzed by GC-MS.[Conclusions]This study provides high-quality raw materials and a theoretical basis for the research of independent flavor blending in cigarette industry enterprises. 展开更多
关键词 Combined application of ultrasonic wave and 4C technique Orthogonal experiment Formula extraction FLAVOR
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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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Analysis of Ultrasonic Emulsification Surgery and Small Incision Cataract Extracapsular Extraction Surgery for Cataract Clinical Treatment Level Improvement
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作者 Chunyan Ji 《Journal of Clinical and Nursing Research》 2024年第2期196-200,共5页
Objective:To analyze the efficacy of ultrasonic emulsification and small incision cataract extracapsular extraction in cataract patients.Methods:96 cataract patients admitted from May 2021 to May 2023 were selected an... Objective:To analyze the efficacy of ultrasonic emulsification and small incision cataract extracapsular extraction in cataract patients.Methods:96 cataract patients admitted from May 2021 to May 2023 were selected and randomly grouped into group A(ultrasonic emulsification)and group B(small-incision extracapsular cataract extraction),with 48 cases each.Results:At 1 week,1-month,and 3 months post-operation,the visual acuity of group A was higher and the astigmatism value was lower than that of group B(P<0.05);at 12h,24h,and 48h post-operation,the intraocular pressure of group A was higher than that of group B(P<0.05);the thickness of macular area of group A was lower than that of group B at 1 week and 1-month post-operation(P<0.05).Conclusion:Ultrasonic emulsification in cataract patients was slightly better than small incision cataract extracapsular extraction in correcting astigmatism,improving visual acuity,and regulating macular thickness.However,due to the high energy of ultrasonic emulsification,the risk of complications such as high postoperative intraocular pressure was higher.Small-incision extracapsular cataract extraction has better application value in economically disadvantaged areas. 展开更多
关键词 CATARACT Cataract ultrasonic emulsification Small incision cataract extracapsular extraction Therapeutic efficacy
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Profiling the effects of microwave-assisted and soxhlet extraction techniques on the physicochemical attributes of Moringa oleifera seed oil and proteins 被引量:1
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作者 Ngozi Maryann Nebolisa Chukwuebuka Emmanuel Umeyor +2 位作者 Uchenna Eunice Ekpunobi Immaculeta Chikamnele Umeyor Festus Basden Okoye 《Oil Crop Science》 CSCD 2023年第1期16-26,共11页
There is a constant search for biomaterials from natural products like plants for food and industrial applications.The work embodied in this report aimed at investigating the effects of microwave-assisted and soxhlet ... There is a constant search for biomaterials from natural products like plants for food and industrial applications.The work embodied in this report aimed at investigating the effects of microwave-assisted and soxhlet extraction(MAE and SE) techniques on the functional physicochemical quality characteristics of Moringa oleifera seed oil and proteins extracts. M. oleifera seeds were ground to fine powders and oil was extracted by microwave-assisted and soxhlet extraction techniques using petroleum ether. Quality attributes including yield percent, moisture content,iodine, saponification, specific gravity, viscosity, p H, thiobarbituric acid, acid and peroxide values were measured. Mineral and vitamin contents, chemical/functional groups, fatty acid(FA) composition, and reducing power of the oil were evaluated. Metabolomics of protein extracted from the defatted powders were analyzed by nuclear magnetic resonance(NMR). M. oleifera oil from MAE and SE methods had good yield(34.25 ± 0.0%,28.75 ± 0.0%), low moisture content(0.008 ± 0.0%, 0.011 ± 0.0%), non-drying and unsaturated, moderately saponified, less dense(0.91 ± 0.01, 0.92 ± 0.02 g m L^(-1)), had Newtonian flow, were weakly acidic, showed good content of FAs, recorded strong potential for long shelf-life, showed stability against oxidative rancidity and enzymatic hydrolysis, had very rich deposits of micro-and macro-nutrients as well as water-soluble and lipidsoluble vitamins, and functional groups in the oil were reflective of its content of long-and medium-chain triglycerides(LCT and MCT). Monounsaturated and saturated fatty acids(MUFA and SFA) were detected and the oil has excellent ferric ion reducing power. NMR metabolomic assay revealed the presence of nine essential amino acids(EAAs) in the protein extract. MAE technique is a feasible and acceptable alternative for high throughput extraction of M. oleifera oil with high yield and excellent quality attributes. The study revealed that MAE did not impart any remarkable advantage(s) on the physicochemical properties of M. oleifera seed oil and protein compared to SE technique. 展开更多
关键词 Moringa oleifera seed Oil microwave-assisted extraction Soxhlet extraction Quality attributes GC-MS assay Metabolomics Reducing power
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Optimal Ultrasonic Extraction of Pachyman from Jiuzihe Poria cocos 被引量:7
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作者 刘丽 徐春 +2 位作者 李可 姜昆 吴鹏 《Agricultural Science & Technology》 CAS 2016年第12期2746-2750,2776,共6页
This study was conducted to extract pachyman to the greatest degree with ultrasonic technology, and to determine the content of pachyman by the phe-nol-sulfuric acid method, so as to choose the optimal technique of ul... This study was conducted to extract pachyman to the greatest degree with ultrasonic technology, and to determine the content of pachyman by the phe-nol-sulfuric acid method, so as to choose the optimal technique of ultrasonic extrac-tion of pachyman. Firstly, the ultrasonic power, extraction time and solid-to-liquid ra-tio were investigated by ultrasonic extraction method. Then, on this basis, a respon-sible surface experiment was designed, to select the optimal process conditions ac-cording to the index of pachyman yield. The optimized ultrasonic water extraction conditions were as fol ow: ultrasonic power of 100 W, extraction time of 30 min, and solid-to-liquid ratio at 1:40. The Oxford cup method was used to study the an-timicrobial activity of pachyman. lt was found that pachyman could significantly in-hibit Bacilus subtilis_and Staphylococcus aureus. 展开更多
关键词 Poria cocos Pachyman ultrasonic extraction Response surface An-timicrobial activity
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Optimal ultrasonic extraction condition and determination of polysaccharides in Tilia amurensis flowers 被引量:2
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作者 穆立蔷 刘立平 马大龙 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第1期77-80,I0003,共5页
Seven extracting temperatures (25, 35, 45, 55, 65, 75, 85℃) and extracting time (30, 40, 50, 60, 70, 80, 90 min) were designed for selecting the optimal extracting time and extracting temperature for ultrasonic e... Seven extracting temperatures (25, 35, 45, 55, 65, 75, 85℃) and extracting time (30, 40, 50, 60, 70, 80, 90 min) were designed for selecting the optimal extracting time and extracting temperature for ultrasonic extraction of T. amurensis flowers. Polysaccharides from T. amurensis flowers were isolated and determined by spectrophotometry. Results show that the optimal ultrasonic temperature was 75℃ and ex tracting time 52 min. The content of polysaccharides in T. amurensis flowers measured by anthrone--H2SO4 colorimetry under 580 nm, was 9.74% with 0.47% of relative standard deviation (RSD, n=3). This study demonstrated that ultrasonic extraction method was simple, and the color of the treated samples was stable in 4 h. The average recovery value for the polysaccharides measured was 99.48%±1.01%, with 0.112% of RSD (n=3). 展开更多
关键词 best extracting condition POLYSACCHARIDES Tilia amurensis flowers ultrasonic extraction
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Ultrasonic Assisted Extraction of Anthocyanins from Strawberry
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作者 孙建霞 翟熙 +3 位作者 张振华 邱瑞霞 欧仕益 白卫滨 《Agricultural Science & Technology》 CAS 2014年第8期1403-1406,1432,共5页
This study aimed to explore the main factors influencing the extraction of anthocyanins from strawberry, such as solid-liquid ratio, concentration of solvent, duration of ultrasonic treatment and ultrasonic power. Acc... This study aimed to explore the main factors influencing the extraction of anthocyanins from strawberry, such as solid-liquid ratio, concentration of solvent, duration of ultrasonic treatment and ultrasonic power. According to the results of sin-gle factor test, an orthogonal experiment was designed to determine the optimum extraction conditions. The effects of the four factors on anthocyanins extraction from strawberry were listed here in an decreasing order: ethanol concentration 〉 solid-liq-uid ratio〉duration of ultrasonic treatment〉ultrasonic power. And the optimal condi-tions of ultrasonic extraction of anthocyanins from strawberry were: ultrasonic treat-ment of 30 min, solid-liquid ratio of 1:15, ethanol concentration of 60% and ultra-sonic power of 300 W. Under such conditions, the content of extracted antho-cyanins was 33.247 mg/100g, which was 1.3 folds higher than that by extraction without ultrasonic treatment. 展开更多
关键词 ultrasonic extraction STRAWBERRY ANTHOCYANIN
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Optimization of Microwave-assisted Extraction Technology of Polyphenols from Loropetalum chinense(R. Br.) Oliv 被引量:1
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作者 刘秀 黄维 +6 位作者 肖珑 陈靖宇 荣蓉 李瑾 唐彩红 谢鹏 金晨钟 《Agricultural Science & Technology》 CAS 2016年第11期2629-2635,共7页
In order to optimize the microwave-assisted extraction technology of polyphenols from Loropetalum chinense (R. Br.) Oliv., the effects of microwave power, ethanol concentration, solid to liquid ratio and extraction ... In order to optimize the microwave-assisted extraction technology of polyphenols from Loropetalum chinense (R. Br.) Oliv., the effects of microwave power, ethanol concentration, solid to liquid ratio and extraction time on polyphenols extraction rate were investigated. On the basis of single-factor test, a four-factor and three-level orthogonal test was designed by response surface method to establish a mathematical model between the response value and various factors. The results showed that the intensity of effect of different influencing factor on polyphenols ex- traction rate ranked as microwave power's〉solid to liquid ratio's〉extraction time's〉 ethanol concentration's. The optimum microwave-assisted extraction conditions for polyphenols from L. chinense were as follows: extraction power 254 W, ethanol concentration 60%, extraction time 12.5 rain and solid to liquid ratio 1:17. Under the optimum extraction conditions, the extraction rate of polyphenols from L. chinense was 19.17%. 展开更多
关键词 Loropetalum chinense (R. Br.) Oily. Potyphenols microwave-assisted extraction technology Response surface analysis
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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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MICROWAVE-ASSISTED EXTRACTION OF GLYCYRRHIZIC ACID FROM LICORICE ROOT-EFFECT OF THE PROPERTY OF SOLUTION ON EXTRACTION OF GA 被引量:53
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作者 Pan Xuejun and Liu Huizhou (Young Scienctist Laboratory of Separation Science & Engineering, State Key Laboratory of Biochemical Engineering, Instigate of Chemical Metallurgy, Chinese Academy of Sciepces, Beijing 100080) 《化工学报》 EI CAS CSCD 北大核心 2000年第S1期240-243,共4页
The property of extraction solution is an important factor influencing the extraction efficiency. In the present work, the effect of the property of solution on extraction of GA was studied, which including the concen... The property of extraction solution is an important factor influencing the extraction efficiency. In the present work, the effect of the property of solution on extraction of GA was studied, which including the concentration of ethanol, ammonia and cation (M+), pH of extraction solution, different kinds of organic solvent etc. The results show that 50%-60%(v/v) ethanol can reach high percentage extraction of GA. If 1% (v/v) ammonia solution was added into 60%(v/v) ethanol, the percentage extraction can be increased from 2.0% to 2.31%. Without ammonia, 50mmol/L [M+] (M+ = K+, NH4+) was added into 60%(v/v) ethanol, percentage extraction of GA can reach about 2.26%. If pH of solution (60% ethanol) was adjust to pH=4.0, it can reach high percentage extraction. If pH of solution (60% ethanol + 50mmol [M+], pH=6.1) was adjust tO PH=4.0, especially M+ is K+ or NH4+, it can reach almost same extraction efficiency as that of 1% ammonia solution + 60% ethanol, and the operation environment can be greatly improved. 展开更多
关键词 glycyrrhizic acid licorice root microwave-assisted extraction
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Polyphenols extracted from Aronia melanocarpa by combined enzymatic and ultrasonication and their antioxidant potential and antimicrobial activity
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作者 Xinzhu Zhang Ming Song +1 位作者 Weizhuo Xu Wei Xu 《Journal of Polyphenols》 2023年第1期35-47,共13页
The extraction of polyphenols from Aronia melanocarpa was carried out using a combination of enzymatic and ultrasound.After single-factor and orthogonal design and experiment,the optimized polyphenol extraction condit... The extraction of polyphenols from Aronia melanocarpa was carried out using a combination of enzymatic and ultrasound.After single-factor and orthogonal design and experiment,the optimized polyphenol extraction conditions were 1%enzyme,1:40 material-to-liquid ratio,55℃,60 min ultrasonication,70%ethanol,and the final extraction amount was 88.634 mg/g,which displayed a 25.15%and 34.08%improvement compared with the single ultrasonication and enzymatic extraction methods,respectively.Significant antibacterial effects of polyphenols were shown against Staphylococcus aureus,Escherichia coli and Bacillus subtilis.Further antioxidation effects were evaluated,and the superoxide anion radical scavenging rate,hydroxyl radical scavenging rate and DPPH free radical scavenging rate reached 45.2%,83.5%and 85.4%,respectively.This combined enzymatic and ultrasonic extraction method exhibited the advantages of high extraction rate,saving solvent consumption and extraction time,but also provided a new method for the development and utilization of natural antimicrobial and antioxidant health products. 展开更多
关键词 Aronia melanocarpa phenolic compounds enzymatic extraction ultrasonication antibacterial effect antioxidation effect
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Extraction of Organochlorine Pesticides in Sediments Using Soxhlet,Ultrasonic and Accelerated Solvent Extraction Techniques 被引量:9
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作者 LANGYinhai CAOZhengmei NIEXinhua 《Journal of Ocean University of China》 SCIE CAS 2005年第2期173-176,共4页
The application of soxhlet, ultrasonic and accelerated solvent extractiontechniques to the analysis of six organochlorine pesticides (α-HCH, β-HCH, γ-HCH, o, p'-DDT,p,p'-DDT and p,p'-DDE) in Taihu Lake ... The application of soxhlet, ultrasonic and accelerated solvent extractiontechniques to the analysis of six organochlorine pesticides (α-HCH, β-HCH, γ-HCH, o, p'-DDT,p,p'-DDT and p,p'-DDE) in Taihu Lake sediment samples is described. It was found that the limits ofquantification ranged from 0.002 μg g^(-1) to 0.004 μg g^(-1), and the recoveries oforganochlorine pesticides with the three extraction techniques were acceptable ( 】80.7%). With amass selective detector, better results were obtained by accelerated solvent extraction usinghexane-acetone (1:1) as compared with soxhlet and ultrasonic extraction. It was shown that theaccelerated solvent extraction was the optimum technique for the analysis of organochlorinepesticides in sediments. The general features of the three extraction techniques are also presented. 展开更多
关键词 organochlorine pesticides Taihu Lake sediments soxhlet extraction ultrasonic extraction accelerated solvent extraction
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Microwave-assisted extraction of polysaccharides from solanum nigrum 被引量:10
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作者 陈晓青 刘覃 +1 位作者 蒋新宇 曾帆 《Journal of Central South University of Technology》 EI 2005年第5期556-560,共5页
The microwave-assisted method was used to extract polysaccharides from solanum nigrum. The optimum experimental parameters, mechanism of the extraction and the effect of microwave-assisted extraction process on the st... The microwave-assisted method was used to extract polysaccharides from solanum nigrum. The optimum experimental parameters, mechanism of the extraction and the effect of microwave-assisted extraction process on the structures of polysaccharides were investigated. The extract was analyzed by the modified phenol-sulfuric acid method at 490nm. The optimum experimental parameters were obtained by orthogonal experiments as follows: extraction time 15min, microwave radiation power 455W and the process ratio of materials mass to solvent volume 1∶20. The results show that compared with the conventional reflux extraction, the microwave-assisted extraction has a higher yield in shorter time, with no effect on the finally obtained polysaccharides as seen from the FT-IR spectra. The scanning electron microscopy images reveal that the mechanism of the extraction is related to the structural changes of the plant cells in different extracting conditions. 展开更多
关键词 solanum nigrum POLYSACCHARIDES STRUCTURE microwave-assisted extraction
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Microwave-assisted Extraction of Isoflavones from Belamcanda chinensis 被引量:6
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作者 龚盛昭 程江 杨卓如 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第4期556-559,共4页
Microwave-assisted extraction (MAE) of isoflavones from Belamcanda chinensis was studied using ethanol as the solvent. The single factor experiment and the orthogonal method were used to optimize the MAE condition. ... Microwave-assisted extraction (MAE) of isoflavones from Belamcanda chinensis was studied using ethanol as the solvent. The single factor experiment and the orthogonal method were used to optimize the MAE condition. It was concluded that two doses of intermittent microwave power radiation, 300 W each for 4 rain, were needed for extraction. The mass ratio of solvent to material was 8:1 and the alcohol mass fraction was 80%. The extracted liquor was then concentrated under vacuum and degreased with petroleum ether. The yield of total isofiavones was about 8.8% and the contents of tectoridin and iridin were 67.6% and 16.3% respectively. Compared with direct-heating extraction (DHE), MAE may shorten extracting duration, reduce solvent consumption, and improve yield and purity of isoflavones from Belamcanda chinensis. 展开更多
关键词 Belamcanda chinensis ISOFLAVONE microwave-assisted extraction TECTORIDIN iridin
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The Optimization of Ultrasonic Extraction Technology of Total Flavonoids in Leaves of Mallotus apelta by Response Surface Analysis Methodology 被引量:9
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作者 Dengfeng ZOU Ruifen FAN +1 位作者 Xiao HUANG Aize XIE 《Medicinal Plant》 CAS 2018年第4期68-72,共5页
[Objectives] Response surface analysis methodology was used to optimize the extraction technology of total flavonoids from Mallotus apelta leaves. [Methods] The total flavonoids were extracted using ultrasonic assiste... [Objectives] Response surface analysis methodology was used to optimize the extraction technology of total flavonoids from Mallotus apelta leaves. [Methods] The total flavonoids were extracted using ultrasonic assisted ethanol extraction,and extraction rate of total flavonoids was taken as evaluation index. On the basis of single-factor experiment,Box-Behnken response surface methodology was employed for selecting the optimum extraction process. [Results]The optimum extraction conditions of total flavonoids were as follows: 75% of ethanol concentration,1∶ 25 of ratio of material to liquid,31 min of ultrasonic time. Under these conditions,the extraction rate of total flavonoids was 1. 115%.[Conclusions] The extraction process obtained by response surface methodology was stable,reasonable,accurate and reliable. It was a feasible method to extract the total flavonoids from M. apelta leaves. 展开更多
关键词 Mallotus apelta Total flavonoids ultrasonic extraction Response surface methodology
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Ultrasonic Extraction of Polysaccharides from Laminaria japonica and Their Antioxidative and Glycosidase Inhibitory Activities 被引量:6
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作者 WAN Peng YANG Xiaoman +4 位作者 CAI Bingna CHEN Hua SUN Huili CHEN Deke PAN Jianyu 《Journal of Ocean University of China》 SCIE CAS 2015年第4期651-662,共12页
In the present study, ultrasonic extraction technique (UET) is used to improve the yield of polysaccharides from Lami- naria japonica (LJPs). And their antioxidative as well as glycosidase inhibitory activities ar... In the present study, ultrasonic extraction technique (UET) is used to improve the yield of polysaccharides from Lami- naria japonica (LJPs). And their antioxidative as well as glycosidase inhibitory activities are investigated. Box-Behnken design (BBD) combined with response surface methodology (RSM) is applied to optimize ultrasonic extraction for polysaccharides. The optimized conditions are obtained as extraction time at 54 min, ultrasonic power at 1050 W, extraction temperature at 80℃ and ratio of material to solvent at 1:50 (g mL-1). Under these optimal ultrasonic extraction conditions, an actual experimental yield (5.75% + 0.3%) is close to the predicted result (5.67%) with no significant difference (P〉0.05). Vitro antioxidative and glycosidase inhibitory activities tests indicate that the crude polysaccharides (LJP) and two major ethanol precipitated fractions (LJP1 and LJP2) are in a concentration-dependent manner. LJP2 (30%-60% ethanol precipitated polysaccharides) possesses the strongest α-glucosidase in- hibitory activity and moderate scavenging activity against hydroxyl radicals (66.09% ±2.19%, 3.0 mg mL-l). Also, the inhibitory activity against a-glucosidase (59.08% ± 3.79%, 5.0 mg mL-1) is close to that of acarbose (63.99% ± 3.27%, 5.0 mg mL-l). LJP 1 (30% ethanol precipitated polysaccharides) exhibits the strongest scavenging activity against hydroxyl radicals (99.80%q-0.00%, 3.0mg mL-1) and moderate a-glucosidase inhibitory activity (47.76%± 1.92%, 5.0 mgmL-1). LJP shows the most remarkable DPPH scav- enging activity (66.20%±0.11%, 5.0mgmL-1) but weakest a-glucosidase inhibitory activity (37.77%±1.30%, 5.0mgmL-1). How- ever, all these LJPs exert weak inhibitory effects against a-amylase. These results show that UET is an effective method for extract- ing bioactive polysaccharides from seaweed materials. LJP 1 and LJP2 can be developed as a potential ingredient in hypoglycemic agents or functional food for the management of diabetes. This study provides scientific evidence and advances in the preparation technology and a hypoglycemic activities evaluation method for seaweed polysaccharides, especially glycosidase inhibition in com- bination with an antioxidative activity evaluation method. 展开更多
关键词 POLYSACCHARIDES Laminariajaponica ultrasonic extraction ANTIOXIDATIVE Α-GLUCOSIDASE a-amylase
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Microwave-assisted Extraction of Rutin and Quercetin from Flos Sophorae 被引量:6
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作者 LIMin-jing YOUJing-yan YAOShuang DINGLan LIUZhong-ying ZHANGHan-qi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第6期703-706,共4页
Three microwave-assisted extraction(MAE) procedures were studied. The first procedure was household microwave oven dynamic extraction(HMODE). The second procedure was special microwave oven bath extraction(SMOBE). The... Three microwave-assisted extraction(MAE) procedures were studied. The first procedure was household microwave oven dynamic extraction(HMODE). The second procedure was special microwave oven bath extraction(SMOBE). The third procedure was microwave resonant cavity dynamic extraction(MRCDE). The results obtained by the three microwave-assisted extraction procedures were compared with those obtained by using traditional Soxhlet extraction. The results indicate that the MAE not only took a shorter time, but also simplified the procedure, and made the extraction a higher yield. At the same time the results obtained by the three MAE procedures were also compared with each other. 展开更多
关键词 microwave-assisted extraction(MAE) Flavonoid RUTIN QUERCETIN Flos Sophorae
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Microwave-assisted Extraction of Effective Compounds from Traditional Chinese Herbal Medicine Ciwujia 被引量:4
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作者 王娟 沈平孃 沈永嘉 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期231-233,共3页
Microwave-assisted extraction (MAE) for active ingredients in Ciwujia was studied by using ethanol as the extractant. Comparing MAE with conventional methods, the former can save the extracting time and increase the c... Microwave-assisted extraction (MAE) for active ingredients in Ciwujia was studied by using ethanol as the extractant. Comparing MAE with conventional methods, the former can save the extracting time and increase the content of the active ingredients in product. As to the operation in MAE, the continuous radiation process is more convenient for the extraction for traditional Chinese medicine than the intermittent radiation process. Optimized by uniform design, MAE was proved to be an effective and novel process for extracting active ingredients in Ciwujia. The optimized MAE conditions are as follows: the microwave power is 510W, the radiation time 30min, the alcohol concentration at 80%, the ratio of solvent to solid material being 5:1, the soaking time 0.5h, and the herbal particle size is (520±19)μm. 展开更多
关键词 microwave-assisted extraction Ciwujia uniform design SAPONINS ISOFRAXIDIN
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Microwave-assisted solvent extraction of castor oil from castor seeds 被引量:4
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作者 Nur Atirah Ibrahim Muhammad Abbas Ahmad Zaini 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第12期2516-2522,共7页
This study was aimed at evaluating the physicochemical properties and oxidation stability of castor oil using microwave-assisted solvent extraction(MAE). MAE was performed using 5% ethanol in hexane as solvent at diff... This study was aimed at evaluating the physicochemical properties and oxidation stability of castor oil using microwave-assisted solvent extraction(MAE). MAE was performed using 5% ethanol in hexane as solvent at different extraction times, power intensities and solvent-to-feed(S/F, ml of solvent to gram of feed) ratios.The process parameters were optimized by statistical approach using historical data design of response surface method(RSM). The oils were characterized for yield, physicochemical properties, dielectric properties and oxidation stability, and comparison was also made with oil extracted using Soxhlet method. Results show that the maximum oil yield of 37% was obtained at 20 min with microwave power intensity of 330 W and S/F ratio of 20. The main fatty acid composition of castor oil is ricinoleic acid. The density, refractive index, dielectric properties and oxidation stability of oils are not affected by the extraction methods and extraction parameters of MAE. However, the MAE-extracted oil is more viscous compared to that by Soxhlet method. With extra caution on oil oxidation, MAE could be a promising solvent extraction method with an 86% less in processing time and a higher yield. 展开更多
关键词 CASTOR SEED CASTOR oil DIELECTRIC properties microwave-assisted SOLVENT extraction OXIDATION stability
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Response surface optimization of microwave-assisted extraction for HPLC-fluorescence determination of puerarin and daidzein in Radix Puerariae thomsonii 被引量:8
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作者 Ying-Kun Liu E Yan +1 位作者 Han-Ying Zhan Zhi-Qi Zhang 《Journal of Pharmaceutical Analysis》 SCIE CAS 2011年第1期13-19,共7页
Microwave-assisted extraction was optimized with response surface methodology for HPLC-fluorescence determination of puerarin and daidzein in Radix Puerariae thomsonii.The optimized extraction procedure was achieved b... Microwave-assisted extraction was optimized with response surface methodology for HPLC-fluorescence determination of puerarin and daidzein in Radix Puerariae thomsonii.The optimized extraction procedure was achieved by soaking the sample with 70% methanol(1∶15,v/v)for 30 min,and then microwave irradiation for 11 min at a power of 600 W.Coupling the extraction process with HPLC-fluorescence presented good recovery,satisfactory precision,and good linear relation.Compared with a method from the Chinese Pharmacopoeia,the proposed method enables higher extraction efficiency and more accurate analytical results.It can be of potential value in quality assessment of Radix Puerariae thomsonii medicinal materials. 展开更多
关键词 microwave-assisted extraction(MAE) response surface methodology(RSM) PUERARIN DAIDZEIN HPLC-fluorescence detection Radix Puerariae thomsonii
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