Comprehensive characterization and identification of chemical constituents in Yangwei decoction using ultra high performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry.

Yangwei decoction, a classical traditional Chinese medicine prescription, has been widely used to treat exogenous cold and internal injury with damp stagnation for many centuries. However, its systematic chemical profiling remains ambiguous, which has hampered the interpretation of pharmacology and the mechanism of its formula. In the present study, ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry method was successfully established for the first time to separate and identify the complicated components of Yangwei decoction. The accurate mass data of the protonated molecules, deprotonated molecules, and fragment ions were detected in positive and negative ion modes. A total of 226 compounds in Yangwei decoction were tentatively identified and unambiguously characterized by comparing their retention times and mass spectrometry data with those of reference standards and literature, including 24 lignans, 18 alkaloids, 9 phenylpropanoid glycosides, 76 flavonoids, 59 triterpenoids, 17 organic acids, 7 gingerols, 8 lactones, and 8 other compounds. The present study provides a novel method of constituents characterization for well-known Chinese medicine prescriptions. The study aims to lay a robust foundation for future research, providing the holistic quality control and pharmacology of Yangwei decoction.