Chemical Profiling and Characterization of Phenolic Acids, Flavonoids, Terpene Glycosides from Vangueria agrestis using Ultra-High Performance Liquid Chromatography/Ion Mobility Quadrupole Time-of-Flight Mass Spectrometry and Metabolomics Approach.

Vangueria agrestis is a shrub indigenous to tropical Africa, belonging to family Rubiaceae and traditionally is used as a decoction for treatment of fever, pain and malaria. The current study was undertaken to investigate the chemical constituents based on precursor exact mass and fragment ion information. The chemical profiling and structural characteristics of chemical constituents from methanolic extracts of dried aerial and roots of V. agrestis and dietary supplements were analyzed using UPLC-QToF coupled with UNIFI platform and multivariate analysis in both negative and positive ion modes. A non-targeted UPLC/MS analysis was carried out to profile the chemical constituents of crude extracts of V. agrestis and seventy-three compounds including reference compounds were identified. The fragments of flavonoids, monoterpene and triterpene glycosides revealed the characteristic cleavage of glycosidic linkages, and the fragmentation pattern provided identity of the sugars. This analytical method provides a fast method for quality assessment of dietary supplements. Finally, a chemometrics approach with multivariate statistical tools was used to visualize the differences between root and aerial parts of plant samples and to find the potential chemical markers that differentiate among these parts of V. agrestis samples and dietary supplements.