淫羊藿总黄酮苷在家兔肠菌中的代谢及葡萄糖酸内酯对其肠菌代谢的抑制作用(英文)

Metabolism of Epimedium-derived Flavonoid Glycosides in Intestinal Flora of Rabbits and Its Inhibition by Gluconolactone

目的:考察淫羊藿总黄酮苷在家兔肠菌中的代谢以及葡萄糖酸内酯对肠菌代谢的抑制作用,旨在帮助揭示淫羊藿总黄酮苷在家兔体内的代谢途径和预防激素性骨坏死作用的物质基础。方法:淫羊藿总黄酮苷与家兔肠菌液经37℃厌氧温孵培养后,在不同时间点经水饱和的乙酸乙酯萃取,并对加入不同浓度(8,12和16mg·mL-1)的葡萄糖酸内酯对淫羊藿总黄酮苷经家兔肠菌代谢的抑制情况进行考察。采用ODS柱和乙腈-水(各含0.1%的甲酸)的流动相梯度洗脱,检测波长为335nm。结果:淫羊藿总黄酮苷在家兔肠菌液中温孵2h时被代谢成淫羊藿次苷Ⅱ,在温孵8h时被代谢成淫羊藿素;葡萄糖酸内酯能够浓度依赖性地抑制家兔肠菌对淫羊藿总黄酮苷的代谢。结论:淫羊藿总黄酮苷能被家兔肠道菌群迅速水解成淫羊藿次苷Ⅱ和淫羊藿素;当葡萄糖酸内酯的浓度为16mg·mL-1时,则能完全抑制家兔肠菌对淫羊藿总黄酮苷的代谢。

AIM：The metabolism of Epimedium-derived flavonoid glycosides （EF,with icariin as the main component） in rabbit intestinal flora and its inhibition by gluconolactone were investigated in this paper to help reveal the metabolic pathway of EF in rabbits and to identify the in vivo bioactive components of EF in the prevention of steroid-associated osteonecrosis.METHODS：EF were incubated at 37 ℃ anaerobically with rabbit intestinal flora,and then water-saturated ethyl acetate was used for sample extraction at different time points.Furthermore,gluconolactone was added at different concentrations （8,12 and 16 mg·mL^-1） to study its inhibition of the metabolism of EF in rabbit intestinal flora.The separation was performed on a ODS column by gradient elution with acetoni-trile-water （including 0.1% formic acid respectively） as mobile phase at detection wavelength of 335 nm.RESULTS：EF were metabolized to icariside Ⅱ in 2 h,and then to icaritin when incubated for 8 h;gluconolactone showed the inhibition of EF metabolism in rabbit intestinal flora in a concentration-dependent manner.CONCLUSION：EF were found to be metabolized rapidly by hydrolysis of rabbit intestinal flora to produce icariside Ⅱ and icaritin;and the total inhibition was achieved by gluconolactone at a concentration of 16 mg·mL^-1.