The optimal coditions were to extract refluently with 70% alcohol as much as ten times of the medicine amount for 0.5 and add 1%HCl as much as 15% of the solvent.

• 用10倍量70%25乙醇和占溶液体积15%25的1%25HC l回流提取0.；5 h的提取方法可以获得较高的大黄素提取率。