银杏黄酮的体外II相代谢及其临床应用银杏黄酮的体外II相代谢及其临床应用

目的建立银杏黄酮体外代谢的研究方法。方法银杏黄酮与鼠肝微粒体在体外共孵育后,用乙醚-丙酮提取,以HPLC法测定剩余的底物浓度。结果在体外孵育液中,银杏黄酮的3种苷元槲皮素、异鼠李素和山萘素在0.2～8 mg·L^-1线性关系良好,定量限为0.1 mg·L^-1(RSD分别小于10.5%,11.9%和11.8%,N=3),方法回收率分别达99.86％～113.8%,100.78%～117.3%和100.71%～116.5%,RSD均小于2%(N=5)。 3种黄酮苷元在不同来源的微粒体中均有较大代谢活性,尤其是经β-萘黄酮诱导的鼠肝微粒体对3种苷元的葡糖醛酸结合反应有较大的催化作用。结论本法可用于银杏黄酮体外代谢的研究。

Ginkgo flavones in in vitro metabolism and its clinical application

AIM: To develop a method for assaying Ginkgo flavones in rat hepatical microsome. METHODS: Quercetin, isorhamnetin and keampferol were added to microsome incubate and incubated for a given time then extracted with ether-acetone. After evaporated, the residue was reconstituted with 100 microL of phosphate buffer solution (pH 2.0)-tetrahydrofuran-methanol-isopropanol (60:15:10:20). An aliquot of 20 microL was injected into the HPLC system. According to the result of estimate by means of HPLC, the results of metabolism of Ginkgo flavones in different conditions was compared. RESULTS: The assay was linear over the rang of 0.2-8 mg.L-1 for Ginkgo flavones. The limit of quantification was 0.1 mg.L-1 (n = 3). The recoveries of three components of Ginkgo flavones were 99.9%-113.8% for quercetin (RSD < 0.8%), 100.8%-117.3% for isorhamnetin (RSD < 1.9%) and 100.7%-116.5% for keampferol (RSD < 1.03%, n = 5). CONCLUSION: The method is simple, fast and accurate. It can be used for investigation of the metabolism of Ginkgo flavones.