Mining Secondary Metabolites of Chassalia curviflora Leaves Using SIRIUS and High-Resolution Mass Spectrometry Data

Abstract

Chassalia curviflora (Wall ex Kurz.) Thwaites is a flowering plant from Rubiaceae family. Previous phytochemical investigation on Chassalia species led to the isolation of benzoic acid, benzoquinone derivatives, flavonoids, monoterpenoid indole alkaloids and its essential oil composition. However, these are still scarce in terms of its scientific report on studied species. This study was carried out to investigate fast screening of secondary metabolites by using data-dependent acquisition (DDA) LC-MS/MS analysis of methanolic extract of the leaf of the C. curviflora in positive ionization mode. The data were analysed using computational mass spectrometry method from molecular structure database search implemented in Sirius. This led in discovering of 13 known secondary metabolites from a distinct tandem MS data. De novo molecular formula annotations and predictions from SIRIUS suggested five major class compounds classified as coumarin, benzofuran, fatty acids, esters and triterpenes. Stigmasterol 12 and β-sitosterol 13 were successfully isolated, thus used to verify the data obtained from the Sirius. With our results, we advocate the MS-based approach as a useful starting method for the dereplication of compounds from the complex crude extract of plants.