Studies on the metabolism of paeoniflorin in human intestinal microflora by high performance liquid chromatography/electrospray ionization/Fourier transform ion cyclotron resonance mass spectrometry and quadrupole time-of-flight mass spectrometry

In this study, a high performance liquid chromatography/electrospray ionization/Fourier transform ion cyclotron resonance mass spectrometry and quadrupole time-of-flight mass spectrometry (HPLC-ESI-FT-ICR MS and HPLC-ESI-QTOF MS2) based on chemical profiling method was established to study the metabolites of paeoniflorin in human intestinal microflora (HIM). By virtue of the high resolution, high speed of HPLC and the accurate mass measurement of FT-ICR MS and QTOF MS2, 31 metabolites in methyl tert-butyl ether (MTBE) layer were detected, and the structures of 16 metabolites were identified. Among them, 13 metabolites (including two new compounds) were found for the first time in HIM transformation in vitro. The results indicated that metabolic pathways of paeoniflorin in HIM contained extensive metabolic reactions. The hydrolysis, oxidization and conjugation were major metabolic pathways, and the glycosidic linkage, ester bond, benzene ring and pinane of the structure were metabolic sites. These results would contribute to better understanding the metabolic mechanism of paeoniflorin, thereby to in-depth study and development of paeoniflorin in medicine.