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出 处:《安徽大学学报(自然科学版)》2005年第4期70-74,共5页Journal of Anhui University(Natural Science Edition)
基 金:安徽省教育厅自然科学基金资助项目(2003kj016)
摘 要:采用超声萃取法从黄蜀葵花中提取天然植物防晒剂,探讨了不同萃取时间、乙醇浓度、料液比、超声温度以及萃取次数对萃取液吸光度的影响.结果表明:以60%的乙醇水溶液为萃取剂,料液比1∶50(g/mL),在50℃超声萃取20min,萃取一次即可得到较满意的结果.以此条件萃取制得的防晒剂粗产品提取率高达36.2%,在250~400nm区间的紫外吸收光谱有两个吸收带,比吸收系数E1%1cm(λmax)分别为1.0×102(259 nm)和73(370nm).超声萃取与溶剂冷浸和索氏提取相比,操作方便,提取时间短,但效率最高.The ultrasonic technology was used to extract natural sunscreen from the blossom of abelmoschus manihot. The effect of time,concentration of alcohol,ratio of solid to liquid and temperature was studied.Experiments show that as the concentration of alcohol is 60%,the ratio of solid to liquid is 1∶50, the temperature is 50℃,extracted one time for 20min,satisfied result can be obtained.And in this condition,the extracting rate of rough natural sunscreen is 36.2%.There are two absorption bands in 250~400nm and E 1%_ 1cm(λ_ max) is 1.0×10 2(259 nm) and 73(370nm).Compared to the immersion method in room temperature and Soxhlet's extraction,ultrasonic wave extraction not only has the advantages of simplify operation and less time but also provides higher extraction rate.
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