Abstract
Understanding the chemical composition of plants is essential for elucidating their evolutionary adaptations and evaluating the pharmaceutical potential of their primary and secondary metabolites. In this study, we compared the primary and secondary metabolites of three closely related Fritillaria species from the Qinghai-Tibetan Plateau using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS). Chemical constituents were qualitatively identified based on accurate mass measurements combined with MS(1) and MS(2) fragmentation information. A total of 72 compounds were identified across the three Fritillaria species. All species exhibited rich chemical diversity and demonstrated considerable medicinal potential. The differential metabolites included several bioactive compounds, such as peimine and verticine 3-glucoside, among others. In addition, F. thunbergii showed unique alkaloids, including zhebeinine, distinguishing it from the other two species. These findings provide a valuable basis for understanding differences in pharmacological metabolism among the three Fritillaria species and highlight newly reported constituents that expand the known chemical diversity of the genus, offering potential implications for species discrimination, quality evaluation, and rational resource utilization.