Gualou Xiebai Baijiu decoction (GLXB), a well-known classic
traditional Chinese medicine prescription, has been widely used to treat
coronary heart diseases for thousands of years in Eastern Asian countries due to its remarkable clinical effect. However, due to lack of in vivo metabolism research, the chemical components responsible for the
therapeutic effects still remain unclear. In this work, a reliable "representative structure based homologous
xenobiotics identification" (RSBHXI) strategy based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC/Q-TOF-MS) were applied to investigate the chemical components in GLXB extracts. As a result, 133 chemical components were characterized based on summarized fragmentation patterns, of which 41 components were confirmed unambiguously with authentic standards. Furthermore, a total of 138 GLXB-related
xenobiotics were identified or tentatively characterized after
oral administration of GLXB extracts. Moreover, to better understand the metabolic pathways of characteristic components in GLXB, metabolites profiles of five steroidal
saponins and two
flavonoids were performed, respectively. Since the metabolic pathways of five representative
saponins had been finished in our previous study, we focused on the in vivo metabolism of two
flavonoids. A total of 36 and 20 metabolites were detected in rat
biological samples after
oral administration of luteolin-7-O-β-D-glucopyranoside and
rutin, respectively. The results indicated that
dehydration, hydrolysis, hydroxylation, methylation, glucuronidation and sulfation were the main metabolic reactions, following the metabolic soft spots of GLXB-related
flavonoids. Taken altogether, this study would be helpful for the further pharmacokinetics, pharmacological evaluation and quality control of GLXB.