中文摘要：

建立一种简单的5α-还原酶抑制剂体外筛选模型,用于20种植物单体物质的5α-还原酶抑制活性检测,以寻求对粉刺治疗有效的药物.以睾酮为底物、NADPH为供氢体,对5α-还原酶体外测定体系进行了优化,并测定了20种中草药标准品的5α-还原酶抑制活性.确定了5α-还原酶反应的最适底物浓度为25μmol/L,最适反应温度为37℃,最适反应pH值为6.5.确定了知母总苷、连翘素、蛇麻酮对5α-还原酶有抑制作用,其半数抑制常数（IC50）分别为12.4、20.8和45.6μg/mL.知母皂、连翘素和蛇麻酮在抗粉刺领域具有潜在应用价值。

英文摘要：

Establishing a simple and easy method to screen 5a-reductase inhibitor from Chinese medicinal herbs active constituents in vitro for cure of acnes in this study. The method was optimized with testosterone as substate and NADPH as proton donor. The optimal 5 α-reductase reaction conditions are： the concentration of substrate is 25 μmol/L, the temperature is at 37℃ and pll is at 6.5. The method was used for screening 20 botanic substances from Chinese medicinal herbs. The results showed that the IC50 total glycosides, forsythin and lupulone, respectively. Rhizoma Anemarrhenae total glycosides, forsythin and lupulone may have potential value for curing aches.