干燥的穿龙薯蓣根茎,粉碎、浸渍发酵磨浆,筛除纤维素,其残渣用HCl-CH₃COCH₃（1：5）混合液直接酸解,萃取,萃取液再经水解4～6h,然后加入冷水,得白色沉淀物,丙酮重结晶得细针状薯蓣皂甙元结晶,mp197～200℃。

Rhizome of Dioscorea nipponica Mak. was allowed to ferment and disintegrate into a paste,cellulose was sifted away and the resulted residue was directly hydrolysed and extracted with HCI-acetone mixture(1:5).After further hydrolysis for 4~6 hours,the solution,yielded diosgenin on addition of cold water,which after recrystallization gave a mp=197-200℃.