酶法及半仿生法提取杜仲叶中绿原酸和黄酮

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

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%。

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.