An UHPLC-QTOF-MS-based strategy for systematic profiling of chemical constituents and associated in vivo metabolites of a famous traditional Chinese medicine formula, Yinchenhao decoction.

Yinchenhao decoction (YCHD), a famous traditional Chinese medicine formula, has been applied for relieving jaundice in China for more than 1800 years. However, the material basis for YCHD is still unclear, and the chemical composition and metabolism characteristic in vivo are undefined, making the potential effective constituents and mechanism of action unclear. Herein, an ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS)-based strategy was applied for the chemical profiling of YCHD, as well as their in vivo prototypes and global metabolites that defined the metabolome. Our results showed that a total of 139 chemicals were identified in YCHD, including 28 organic acids, 12 monoterpenoids, five diterpenes, three triterpenoids, 17 iridoids, 23 anthraquinones, 26 flavonoids, four coumarins and 21 other types. Moreover, 58 prototypes and 175 metabolites were found in rat biological samples after oral administration of YCHD; those distributed in plasma, liver, intestine and feces were suggested to be potentially effective substances. Oxidation, hydrogenation, decarboxylation and conjugations with methyl, sulfate and glucuronate were considered as the predominant metabolic pathways in vivo. In conclusion, this is a systemic study of chemical constituents and in vivo metabolome profiles of YCHD, contributing to the material basis understanding and further mechanism research.