酶法及半仿生法提取杜仲叶中绿原酸和黄酮

为优选杜仲叶中绿原酸和黄酮提取最佳工艺,以绿原酸和黄酮含量为考察指标,通过正交实验对半仿生法和酶法两种提取方法进行了优化。半仿生法的工艺条件为:杜仲叶为原料,以磷酸氢二钠-柠檬酸的缓冲溶液作为提取液,m(杜仲叶)∶m(提取液)=1∶20,提取液pH分别为2.0,7.5,8.3,在70℃,每次提取1 h,提取3次;在此条件下,绿原酸的得率达1.44%,黄酮得率达0.044%。果胶酶提取的工艺条件为:杜仲叶为原料,以磷酸氢二钠-柠檬酸的缓冲溶液作为提取液,m(杜仲叶)∶m(提取液)=1∶15,果胶酶酶解温度为60℃;提取液pH为3.6;每5 g杜仲叶中加入质量分数为0.5%果胶酶1.5 mL,酶解2 h后,升温至80℃,每次1 h,提取3次;在此条件下,绿原酸的得率达1.29%,黄酮得率达0.043%。

Semi-bionic Extraction and Enzymic Treatment for Extraction of Chlorogenic Acid and Flavonoid in Eucommia ulmoides Olive

The extraction processes for chlorogenic acid and flavonoid in leaves of Eucommia ulmoides Olive by semi-bionic extraction and enzymic treatment were investigated using the contents of chlorogenic acid and flavonoid as indexes.The optimized extracting conditions were determined experimentally with orthogonal design.For semi-bionic extraction,the leaves were extracted with 20 times the weight of sodium hydrogen phosphate and citric acid buffer solutions of pH=2.0,7.5 and 8.3 at 70 ℃ for 1 h 3 times.The extracting ratios of chlorogenic acid and flavonoid are 1.44% and 0.044% respectively.For enzymic treatment,the leaves were hydrolyzed with enzymes at pH=3.6,60 ℃ and each 5 g Eucommia ulmoides Olive with 1.5 mL 0.5% enzymes for 2 h,followed by extraction at 80 ℃ with 15 times the weight of sodium hydrogen phosphate and citric acid buffer solution for 1 h 3 times.The extracting ratios of chlorogenic acid and flavonoid are 1.29% and 0.043% respectively.