Synergistic anticancer effect of combined use of (plumbagin, cis-Isoshinanolone, 3-O-β-glucopyranosyl plumbagic acid) isolated from Plumbago zeylanica, induces cell death through apoptosis in human HepG2 cancer cells

Plumbago zeylanica L., a traditional medicinal plant, has shown remarkable anti-cancer properties, making it imperative to delve into its chemical composition and biological effects. Fractions extracted from the roots of P. zeylanica exhibited cytotoxic activity, prompting further investigation through bioassay-guided fractionation and mass-directed isolation. This led to the discovery of three compounds: plumbagin (1), cis-Isoshinonolone (2), and 3-O-{beta}-glucopyranosyl plumbagic acid (3). The chemical structures of these compounds were elucidated through the analysis of 1D/2D NMR and MS data. Subsequent evaluation of compounds 1-3 for cytotoxic activity against human hepatoma cancer cells (HepG2) revealed potent effects, with all three compounds demonstrating IC50 values of < 0.5 {micro}M. The combined action of these bioactive compounds in P. zeylanica was found to possess effective anti-cancer properties, exhibiting superior cytotoxic activity compared to individual compounds. Specifically, compound 3 emerged as the most potent natural product in the series, displaying an IC50 value of 0.1 {micro}M against the HepG2 cell line. In conclusion, compounds 1, 2, and 3 from P. zeylanica showcase significant in vitro cytotoxic activity against HepG2 cells, underscoring their potential as promising candidates for further anti-cancer research and development.