Optimization of Extraction Process of Flavonoids from Ginkgo biloba L. Leaf

[Objective] To optimize the extraction process of flavonoids from Ginkgo biloba L.leaf,so as to provide basis for the refining of Ginkgo biloba L.leaf flavonoids.[Method] Content of flavonoids was determined by UV spetrophotometry.By employing single factor test,effect of ethanol concentration,reflux temperature and extraction duration on yield of flavonoids from Ginkgo biloba L.leaf,optimizing the extraction conditions.[Result] The optimal extraction conditions were determined to be: extracting solvent of 70% ethanol,extraction temperature of 80 ℃,extraction duration of 3.0 h.Under the optimum extraction process,content of flavonoids in Ginkgo biloba L.leaf reached 1.520 6 mg/ml.[Conclusion] The optimal extraction conditions were obtained in this study,which provided basis for refining of Ginkgo biloba L.leaf flavonoids.