A comprehensive study of the metabolism of flavonoid oroxin B in vivo and in vitro by UHPLC-Q-TOF-MS/MS

•The metabolism of oroxin B, a major flavonoid from Oroxylum indicum (L.) Vent, was comprehensively investigated in rats.•UHPLC-Q-TOF-MS/MS was developed for detection of metabolites.•A total of 30 metabolites in rats, 8 metabolites in liver microsomes and 18 metabolites in intestinal bacteria were identified.•The metabolic mechanisms of oroxin B were generalized firstly.•The relative contents of oroxin B and related metabolites in rat, liver microsomes and intestinal bacteria were semi-quantified.