Host-Dependent Metabolomic Variations in Viscum coloratum Revealed by UHPLC-Q-TOF-MS/MS and Integrated Annotation...

Viscum coloratum (Kom.) Nakai, a widely distributed hemiparasitic medicinal plant in Asia, exhibits host-influenced metabolic traits that remain inadequately characterized. To further investigate this issue, an untargeted metabolomics approach was employed to comprehensively delineate host-dependent metabolic variation. Ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS), a powerful analytical platform for untargeted metabolomics, was used to examine samples collected from two host species in Hubei Province, China. Differential metabolites were screened through multivariate chemometric analysis and characterized using an integrated annotation strategy to ensure systematic and reliable identification. Sixty-eight differential constituents were annotated and mainly assigned to phenylpropanoids, polyketides, lipids and lipid-like compounds, and organic acids and derivatives. These classes represented the major metabolic groups associated with host-dependent variation among the samples analyzed in this study. Furthermore, an exploratory 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay revealed significant differences in antioxidant capacity between the two groups, suggesting that host plants may influence the pharmacologically relevant properties of V. coloratum. These findings highlight the importance of considering host factors in its quality control, provide a comprehensive framework for differential metabolite identification, and enhance the understanding of the metabolic characteristics of V. coloratum.