Chemical profiling and identification of Radix Cudramiae and their metabolites in rats using an ultra-high-performance liquid chromatography method coupled with time-of-flight tandem mass spectrometry

Radix Cudramiae, known as "Chuan-Po-Shi" in China, is a herbal medicine widely used in the southwest of the country, especially applied by the Miao and Zhuang nationalities for the treatment of liver diseases, such as acute liver injury and liver fibrosis. As a kind of ethnomedicine, the report on its chemical analysis was still blank, which restricted its clinical application. Therefore, this paper aimed to illustrate the chemical characteristics of Radix Cudramiae. A rapid analytical strategy based on ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry was developed to profile the natural small-molecular compounds in Radix Cudramiae, as well as the related prototypes and their metabolites in rats after drug administration. As a result, a total of 74 compounds were detected in the aqueous exact of Radix Cudramiae. In vivo, 45 chemicals including 16 prototypes and 29 metabolites in rat serum, along with 35 chemicals including 17 prototypes and 18 metabolites in rat liver, were screened out and identified. For the first time, the chemical constituents of Radix Cudramiae and their metabolic characteristics were discovered. It was hoped that this work would be beneficial for the safe and effective application of Radix Cudramiae in a clinic.