Qualitative and Comparative Analysis of Chemical Constituents in Epimedii Folium From Four Species Based on UPLC‐ZenoTOF‐MS/MS

Epimedii Folium (EF) is frequently used in clinical as traditional Chinese medicine with a long history in China. The Pharmacopoeia of the People's Republic of China (2020 Version) contains four species of the plants of the genus Epimedium as its medicinal sources, namely, Epimedium brevicornu Maxim (EBM), E. sagittatum (Sieb. et Zucc) Maxim (ESM), E. pubescens Maxim (EPM), and E. koreanum Nakai (EKN). However, the available studies on a comprehensive analysis of the chemical constituents in the above four species are much scarce. The objective of this study is to establish a method which uses ultra-high performance liquid chromatography coupled with time-of-flight tandem mass spectrometry (UPLC-ZenoTOF-MS/MS) to identify and characterize the chemical constituents in samples from different species. At the same time, multivariate statistical analysis is applied to screen the differential chemical constituents among different species. A total of 116 constituents were identified from different species of EF; and the possible cleavage pathways of various types of constituents were preliminarily inferred based on the fragmentation behavior of the main constituents. Besides, 23 differential characteristic constituents were screened based on variable importance in projection (VIP) value and p-value, of which nine constituents were common differential constituents. The intrinsic quality of EF was thoroughly assessed in this work using metabolomic analysis based on UPLC-ZenoTOF-MS/MS, which provides basic information for the identification of different varieties of EF, and serves as an experimental foundation for the sensible use of EF from various variations in therapeutic practice.