Chemical Constituent Analysis of Moringa oleifera Leaves based on High-performance Liquid Chromatography-quadrupole Time-of-flight Tandem Mass Spectrometry/Mass Spectrometry Combined with Molecular Network Technology

Objective: Moringa oleifera Lam. ( M . oleifera ) leaves are from a high-economic-value crop and exhibit multiple pharmacological effects, such as hypolipidemic and hypoglycemic activities. However, the studies on the pharmacological basis of M . oleifera leaves (MOL) were not complete, and the identification of its active constituents was not sufficient. Materials and Methods: High-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry/mass spectrometry (HPLC-Q-TOF MS/MS) and molecular network were used to identify the constituents of MOL in this paper. The chemical constituents of MOL were identified using HPLC-Q-TOF MS/MS based on the retention time and fragment ion information. The molecular network of Global Natural Products Social Molecular Networking (GNPS) was constructed according to MS/MS similarity, and molecular clusters were visualized using Cytoscape software. Results: The method was successfully applied to identify the chemical constituents of MOL, and 202 compounds were identified using the GNPS platform, the Massbank database, and references. There were 55 organic acid derivatives, 16 nucleosides derivatives, 21 benzenoids, 21 organic oxygen compounds, 44 phenylpropanoids, and polyketides, 10 lipid-like molecules, 3 alkaloid derivatives, 6 organoheterocyclic compounds, 1 organic nitrogen compounds, and 25 no matches. It was inferred that 128 constituents were identified from MOL for the first time. Conclusions: The results extended our understanding of MOL, and the strategy could be exemplary for future comprehensive identification of medicinal plant constituents. Meanwhile, it could provide a novel idea for the analysis of medicinal plants, and has a certain guiding significance for the quality control and evaluation of medicinal plants.