Identification of Chemical Constituents and Metabolites of YinChen WuLing Powder In Vitro and In Vivo Based on UHPLC‐Q‐Orbitrap HRMS

ABSTRACT YinChen WuLing powder (YCWLP) is an ancient prescription medicine consisted of six herbal medicines, which has definite therapeutic effects on clearing heat and eliminating dampness, strengthening spleen, and removing turbidity. YCWLP is clinically used for the treatment of cholestatic liver diseases, it has significant hepatoprotective effects on liver fibrosis and hyperlipidemia. Although the in vitro components of YCWLP have been reported, the in vivo pharmacodynamic components and metabolic transformation in blood and liver still require systematic analysis. In this study, we systematically identified its in vivo components and metabolites in rat plasma and liver after oral administration for the first time. A chemical composition database of YCWLP was established. The detection method based on UHPLC‐Q‐Orbitrap HRMS and Xcalibur 4.2 software were used to identify the components of YCWLP in vitro and in vivo. Then, the differences of metabolites between the blank group and the YCWLP group were compared to screen potential pharmacodynamic markers. Finally, a total of 102 compounds were identified in YCWLP, including 29 terpenoids, 24 organic acids, 18 flavonoids, 5 coumarins and 26 other compounds. Meanwhile, 64 prototype components and 66 metabolites related to YCWLP were found in rat plasma. Sixty‐five prototype components and 54 metabolites related to YCWLP were found in the rat liver. The main metabolic pathways of YCWLP in rats include hydrolysis, hydroxylation, methylation, and sulfation. In summary, this study elucidated  the chemical constituents and metabolites of YCWLP in vitro and in vivo by UHPLC‐Q‐Orbitrap HRMS technology and Xcalibur 4.2 analysis software, which provided the proof for the discovery of pharmacodynamic substances of classic prescriptions.