目的 观察大鼠肠道菌群对紫丁香苷的体外代谢转化作用。方法 将紫丁香苷与离体大鼠肠道菌群的孵育液分别培养0、4、8、12、24、48 h后取样,经正丁醇萃取后采用HPLC和LC-MS法对代谢产物进行定性和定量分析;扩大培养24 h的孵育液经正丁醇萃取后,采用ODS柱色谱和重结晶方法分离制备代谢产物,NMR法鉴定其结构。结果 大鼠肠道菌群对紫丁香苷具有显著的代谢转化作用。在0～48 h代谢组的孵育液中共检测到2个代谢产物芥子醇(M₁)和右旋丁香树脂酚(M₂)。12 h时有81%的紫丁香苷被代谢转化,24 h时紫丁香苷已经完全被代谢转化;并且检测到12 h之前的主要代谢产物为M₁,24 h后的主要代谢产物为M₂,且24 h后未能检测到M₁。结论 在离体条件下,大鼠肠道菌群可以在24 h内将紫丁香苷完全代谢转化为M₁,然后再将M₁代谢转化为M₂,且8～12 h内转化紫丁香苷的速率最快。

Objective To study the in vitro metabolic transformation of syringin by rat intestinal flora in vitro. Methods When syringin was incubated for 0, 4, 8, 12, 24, and 48 h with rat intestinal flora in vitro, the incubation medium was respectively extracted with n-BuOH, and then HPLC and LC-MS were applied for the qualitative and quantitative analysis of the metabolites. The metabolites were extracted with n-BuOH, isolated by ODS column chromatography, and recrystallization from the extended medium after 24 h of incubation, and their structures were determined on the basis of the NMR experiments. Results Syringin could be easily metabolized by rat intestinal flora in vitro. About 81% of the syringin was metabolized at 12 h, and it was completely metabolized at 24 h. Two metabolites, sinapyl alcohol (M₁) and (+)-syringaresinol (M₂), in the incubation medium of experimental group were identified within 48 h. The major metabolite was M₁ during the first 12 h, and M₂ was the only metabolite identified after 24 h. Conclusion In vitro, syringin could be completely metabolized to M₁, and then converted into M₂ by rat intestinal flora within 24 h, and the metabolism of syringin to M₁ is proceeded most rapidly in 8~12 h.

国家自然科学基金资助项目(81270054,30901954);广东省自然科学基金资助项目(9451040701003203);广东省优秀青年教师培养计划(Yq2013045);广州市珠江科技新星专项(2011J2200047)