Characterization of global metabolic profile of Zhi-Zi-Hou-Po decoction in rat bile, urine and feces after oral administration based on a strategy combining LC-MS and chemometrics.

Identification of metabolic profile of traditional Chinese medicine in vivo is always a challenge task. Usually, screening out and identifying the exogenous compounds manually from total ion chromatograms (TICs) of biologic samples is time-consuming and strenuous. In this study, a systematic identification strategy based on LC-MS was adopted to clarify the metabolic profiling of Zhi-Zi-Hou-Po decoction (ZZHPD) in rat. Bile, urine and feces samples of rat were obtained after oral administration and then analyzed by LC-MS after proper preparation. The xenobiotics were screened out from TICs globally and rapidly by untargeted metabolomics-driven strategy (UMDS) based on the combined of XCMS online (a web-based platform to process LC-MS data), MetAlign (a software to process LC-MS data) and SIMCA-P (a software for data analysis). Most of the xenobiotics were identified by means of series product ions filtering (sPIF), which was based on the database-hit of ZZHPD (including prototype and metabolites). Then the unmatched constituents were identified tentatively and their source and metabolic pathway were clarified by using diagnostic fragment ions strategy (DFIS). As a result, a total of 83 compounds including 44 prototype compounds and 39 metabolites were rapidly identified or tentatively characterized from the biologic samples, and among them, four of which were found for the first time. Further research on the correlations of these prototype compounds and metabolites revealed that glucuronidation is the main metabolic pathways of ZZHPD in rat bile and urine, while prototype compounds were the abundant ingredients detected in rat feces.