Comparative Characterization of Phytochemicals and In Vivo Metabolites of Aqueous and Ethanol Extracts of Callicarpa nudiflora by UHPLC‐Q‐TOF‐MS/MS and Molecular Networking Combined Multivariate Statistical Methods

Callicarpa nudiflora Hook. et Arn. (C. nudiflora), a traditional Chinese medicine, is traditionally used to treat bacterial infections, hepatitis, and hemorrhage. However, its chemical constituents and in vivo metabolic profile have not yet been systematically elucidated, and comparisons of different extracts are still lacking. This study aimed to systematically characterize and compare the in vitro chemical constituents and in vivo metabolites of aqueous (CNW) and ethanol (CNE) extracts of C. nudiflora. A total of 86 chemical constituents were identified in C. nudiflora using UHPLC-Q-TOF-MS/MS combined with molecular networking (MN), including 33 flavonoids, 18 phenylethanoid glycosides, 17 iridoids, 9 phenylpropanoids, 8 terpenoids, and 1 other compound. Based on the identified in vitro constituents and metabolic rules, 12 prototypes and 53 metabolites were further confirmed and annotated in vivo. Furthermore, PCA and OPLS-DA revealed 21 differential in vitro constituents and 16 in vivo compounds between CNW and CNE. These findings indicated that extraction solvent markedly influences the chemical composition and metabolic behavior of C. nudiflora. Overall, this study provides a comprehensive and integrated characterization of phytochemicals and in vivo metabolic profiles of C. nudiflora, offering a robust analytical framework for the comparative evaluation and quality control of different extracts.