Study on extracting Flavonoids from the Leaves of Ginkgo Biloba by Ultrasonic

Objective:To investigate the extraction of flavonaids from the Leaves of Ginkgo Biloba by Ultrasonic.Methods:The extracting congditions of flovonoids from the Leaves of Ginkgo Biloba were optimized by orthogonal design.Spectrophotometry was used to detemine the congtent of flavonids.Results:The optimal extracting conditions were under the 100% ultrasonic power,ultrasonic time was 45 min,the ratio of solvent to feedstock was 12:1,alcohol concentration was 30%,extraction 2 times.The rate of extraction was up to 1.2% by detemine,the yield of ultrasonic extraction was higher about 1.5 fold than that of ethanol-resin adsorption method.Conclusion:This extraction process merits have the advantage of low cost,high recovery and low retained level of organic solvent.