Shimizu K, Amagaya S, Ogihara Y
J Pharmacobiodyn. 1985 Sep;8(9):718-25. doi: 10.1248/bpb1978.8.718.
Structural transformation of saikosaponin a and saikosaponin d, main components of Bupleuri Radix, were investigated using rat gastric juice (pH 1.5) and mouse intestinal flora in vitro and the excretion of saikosaponin derivatives in rat feces was also studied. Quantitative analysis of saikosaponins and their derivatives was carried out by high performance liquid chromatography. By the incubation of saikosaponins in rat gastric juice, saikosaponin a decreased with time dependently. After 3 h, saikosaponin a disappeared completely and saikosaponin b1 which possessed heteroannular diene moiety at C-11,13(18) and saikosaponin g which possessed homoannular diene moiety at C-9(11),12 were detected with the ratio of 3:1. On the other hand, saikosaponin d rapidly changed to only saikosaponin b2 (heteroannular diene structure) completely 30 min after the incubation. Next, by the anaerobic incubation of saikosaponin a with mouse intestinal flora, the formation of saikogenin F, a genuine aglycone of saikosaponin a, reached to the maximum 1 h after the incubation and its yield was 80%. A minor peak of prosaikogenen F, a monofucoside of saikogenin F, was also detected at 15 min. By the same procedures, saikosaponin b1, g, d and b2 also changed to the corresponded prosaikogenin A, H, G and D and saikogenin A, H, G and D with the almost similar pattern to that of saikosaponin a. Finally, the contents of nine excreted metabolites from saikosaponin a, 5 and 20 mg/kg, in feces after its oral administration was investigated using fasted or non-fasted rats.(ABSTRACT TRUNCATED AT 250 WORDS)
利用大鼠胃液（pH 1.5）和小鼠肠道菌群在体外研究了柴胡的主要成分柴胡皂苷a和柴胡皂苷d的结构转化，并研究了柴胡皂苷衍生物在大鼠粪便中的排泄情况。通过高效液相色谱法对柴胡皂苷及其衍生物进行定量分析。将柴胡皂苷在大鼠胃液中孵育后，柴胡皂苷a随时间依赖性降低。3小时后，柴胡皂苷a完全消失，并检测到在C-11,13（18）位具有异环二烯部分的柴胡皂苷b1和在C-9（11）,12位具有同环二烯部分的柴胡皂苷g，其比例为3:1。另一方面，柴胡皂苷d在孵育30分钟后迅速完全转变为仅柴胡皂苷b2（异环二烯结构）。接下来，将柴胡皂苷a与小鼠肠道菌群进行厌氧孵育，柴胡皂苷a的真正苷元柴胡皂苷元F的形成在孵育1小时后达到最大值，产率为80%。在15分钟时还检测到柴胡皂苷元F的单岩藻糖苷原柴胡皂苷元F的一个小峰。通过相同的程序，柴胡皂苷b1、g、d和b2也以与柴胡皂苷a几乎相似的模式转变为相应的原柴胡皂苷元A、H、G和D以及柴胡皂苷元A、H、G和D。最后，使用禁食或未禁食的大鼠研究了口服给予柴胡皂苷a 5和20 mg/kg后粪便中九种排泄代谢物的含量。（摘要截断于250字）
