Metabolic profile of Cortex Fraxini in rats using UHPLC combined with Fourier transform ion cyclotron resonance mass spectrometry

Abstract

Cortex Fraxini is a widely used traditional Chinese medicine (TCM) used for the treatment of gout or hyperuricemia. In this study, a reliable and sensitive ultra-high performance liquid chromatography coupled with Fourier transform ion cyclotron resonance mass spectrometry (UHPLC-FT-ICR-MS) method was developed for systematical screen and identification of the metabolic profile in rats after oral administration of Cortex Fraxini. The chromatographic separation was performed on a Universil XB C18 column (150 mm × 2.1 mm, 1.8 μm; Kromat, USA) and eluted by a gradient program. The identification was achieved on a Bruker high resolution spectrometer in positive ion mode. According to the result, a total of 81 constituents, including 29 prototype compounds and 52 metabolites were tentatively identified and validated by MS data and fragment ions from MS/MS spectra. The parents of all identified metabolites were assigned, and the metabolites were mainly coumarin derivatives. In conclusion, the newly established UHPLC-FT-ICR-MS method with high resolution and sensitivity was an effective approach for the identification of prototypes and metabolites of Cortex Fraxini in vivo. These results provided significant information about the metabolic profile of Cortex Fraxini in vivo and also laid a solid foundation for further pharmacokinetic and pharmacological research of this TCM.