银杏叶总黄酮的提取分离工艺研究

Study on the Extraction and Isolation Technology of Total Flavonoids in Leaves of Ginkgo Bilobal

采用紫外分光光度法测定银杏叶中总黄酮的含量;通过单因素试验考察提取溶剂、料液比、浸提时间、浸提温度对银杏黄酮得率的影响,并用正交试验确定了银杏黄酮提取的最佳工艺;通过不同型号吸附树脂对银杏黄酮吸附效果的比较,确定了吸附树脂的型号,并考察了不同洗脱液的洗脱效果,筛选出最佳洗脱液。试验得到最佳制备工艺为:以50%乙醇为提取剂,料液比为1∶20,浸提时间为6.0h,浸提温度为90℃;以D101型大孔树脂对提取液进行吸附纯化,用30%乙醇进行洗脱分离。利用此工艺制备的银杏叶提取物中黄酮含量达35%,银杏酸含量低于5×10-6。

To optimize the extraction and isolation of total flavanoids from leaves of ginkgo bilobal, the contents of total flavonoids were measured by ultraviolet spectrophotometry. Single factorial experiments were used to study the effects of extraction solvent, material-liquid ratio, extraction time and temperature on the extraction rate of gingko flavonoids. Based on the results of single factorial experiments, the orthog- onal test of factors were proceaded. The optimum model of resin was selected by comparing the adsorption rate of different resins for gingko flavonoids,and after observing the effects of several different decolouri- zers,the best solvent among them was chosen. The optimum conditions were concluded as follows.50 % al- cohol as extractant,material-liquid ratio 1 ：20, extraction time 6 h and extraction temperature 90℃. The extract was purified by D101 macroporous resin, and then eluted by 30% alcohol. By this method, the con- tent of flavonoids in extract of ginkgo biloba leaves was 30 %, and the content of ginkgolic acids was below 5×10-6.