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
应用密闭微波辅助提取法提取玄参中有效成分玄参苷,考察了微波提取条件(包括溶剂、样品粒径、提取时间、固-液质量体积比和提取次数等)对玄参中提取玄参苷收率的影响,结果表明:溶剂为70%乙醇,玄参的粒径为180目,提取时间为10 m in,料液...应用密闭微波辅助提取法提取玄参中有效成分玄参苷,考察了微波提取条件(包括溶剂、样品粒径、提取时间、固-液质量体积比和提取次数等)对玄参中提取玄参苷收率的影响,结果表明:溶剂为70%乙醇,玄参的粒径为180目,提取时间为10 m in,料液比为1∶20及提取次数为2次时,玄参苷的提取率最佳。并且与常压微波辅助提取法、超声波提取法及索氏提取法进行了比较,本法具有快速、高效、绿色环保的优点。展开更多
基金Supported by Universiti Teknologi Malaysia through 415 Flagship(Grant No.03G70)
文摘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.
文摘应用密闭微波辅助提取法提取玄参中有效成分玄参苷,考察了微波提取条件(包括溶剂、样品粒径、提取时间、固-液质量体积比和提取次数等)对玄参中提取玄参苷收率的影响,结果表明:溶剂为70%乙醇,玄参的粒径为180目,提取时间为10 m in,料液比为1∶20及提取次数为2次时,玄参苷的提取率最佳。并且与常压微波辅助提取法、超声波提取法及索氏提取法进行了比较,本法具有快速、高效、绿色环保的优点。
文摘采用微波辅助石油醚/乙醇双液相萃取技术提取樟芝发酵液中的挥发油,并考察了其对7种皮肤癣菌的最低抑制浓度(MIC)。优化的提取条件为:乙醇体积浓度56%,石油醚体积浓度30%,固液比1∶50,微波功率380 W,微波时间90 s。此时,挥发油的提取率为0.69%,真菌MIC为5-20 m L/L。微波辅助双液相萃取挥发油耗时短,提取率高,且获得的挥发油抗皮肤癣菌效果显著。