银杏叶以65%乙醇回流提取,减压浓缩,ZTC澄清剂沉降,酸性吸附,酸水和酸性25%乙醇洗涤,70%乙醇洗脱,喷雾干燥,加入由沉降残渣中分离的银杏总内酯,可以得到质量合格而稳定的银杏叶提取物(GBE),其黄酮和内酯含量分别达到26%和6%以上。

Technical conditions for the preparation of Ginkgo biloba extract are optimized. The leaves of G.biloba areextracted with 65% ethanol under reflux. The concentrated extract is then treated with water,clarified and then filtred. The necessary components in the filtrate are adsorbed on macro reticular resin,and eluated with 70% ethanol. The alcoholic eluate after concentration,was spray dried and G. biloba lactones which have been prepared from the residue during clarifies treatment by means of column chromatography was added to give the final G.biloba extract with a flavonoid content>26% and lactone content>6%.