Study on Extraction of Flavonoids from Ginkgo biloba Leaves and Antioxidant Action in vitro

Taking the leaves of Ginkgo biloba as material,the single factor(solid-liquid ratio,extraction time,extraction temperature,extraction pH) on extraction rate of flavonoids from Ginkgo biloba were studied,using borax-calcium hydroxide water as solvent extraction,and the extraction methods were optimized by orthogonal test;the antioxidation were studied by oil test.The results showed that the effect of flavone content from Ginkgo biloba leaves were in the order:extraction temperatureratio of liquor to materialextraction time=extraction pH,optimum extraction technology for A1B2C2D2,namely combination of liquid ratio was 1∶30,extraction pH 8,extraction temperature 80℃,the extraction time was 3 h,under the conditions of flavone in Ginkgo biloba extraction rate was 2.67%.Ginkgo biloba flavonoid on lard oxidation had obvious inhibition effect.With the increasing concentrations of antioxidant properties of extracts,the initial presentation of gradually increasing,when adding 0.20% to achieve the best antioxidant effect,the oxidation resistance of vitamin C as antioxidants;when the extract was added volume continued to increase,the antioxidant effect declined.