Study on the extraction and antioxidant activity of total flavones from ginkgo leaf

Using the microwave assisted alcohol extraction process of ginkgo leaf flavonoids,the optimal extraction process and the antioxidant activity of products were studied.Research showed that the affecting of the microwave extraction was the concentration of ethanol the ratio of material to liquid microwave time microwave power.The optimal extraction conditions were as follows:ethanol concentration was 90%,the ratio of material to liquid was 1∶ 40(g/mL),microwave extraction time was 20 min,microwave power was 600 W.In the experiment of the oxidation resistance,the ginkgo leaf flavonoids had the strong scavenging function to superoxide anion,hydroxyl radical and DPPH free radical,which was strengthened with the amount increasing of flavonoids.The antioxidant activity of total flavones of ginkgo leaf was stronger than the same concentration of vitamin C.