A comparative UPLC-MS-based metabolomics approach for distinguishing four different cultivars of Qiai (Artemisia argyi Lévl. et Van.)

The Artemisia argyi Lévl. et Van. (A. argyi) from Qichun County, Hubei Province, China, also known as Qiai, is the most important crop in the region. The quality of Qiai can be influenced by the cultivar, which is highly associated with its metabolite components. In this study, 63 batches of Qiai samples from four cultivars, Xiangai (XA), Wujian (WJ), Qijian (QJ), and Baiai (BA), were investigated using untargeted ultra-performance liquid chromatography–mass spectrometry (UPLC-MS) and chemometrics. In total, 44 metabolites were tentatively identified by combining ultra-performance liquid chromatography time-of-flight mass spectrometry (UPLC-Q-TOF/MS) data with the UNIFI platform and its embedded Traditional Medicine Library. Combining principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), and orthogonal partial least squares discriminant analysis (OPLS-DA), twelve chemical markers were found to distinguish the four cultivars, showing a high degree of cultivar variability. Five of these compounds were quantified by ultra-performance liquid chromatography triple-quadrupole mass spectrometry (UPLC-TQ-MS/MS) to obtain more accurate content information. This comprehensive study constitutes a valuable reference for distinguishing the four Qiai cultivars, as well as other cultivars, and has implications for Qiai breeding.