Chemical Constituents of Excoecaria cochinchinensis with Cytotoxic, Antioxidant, Tyrosinase, and α-Glucosidase Inhibitory Activities

This study aimed to investigate the chemical constituents and bioactivities of the pure compounds from Excoecaria cochinchinensis Lour. , Euphorbiaceae. Eleven known compounds, including four triterpenoids, four sterols, two phenolic compounds, and a dipeptide, were isolated from E. cochinchinensis. Their structures were confirmed through spectroscopic analysis and compared with the existing literature. Eight compounds have been identified in this species for the first time. Based on the traditional medicinal use of E. cochinchinensis, the isolated compounds were evaluated for cytotoxicity against MCF-7, A549, and HeLa cell lines, as well as for antioxidant, α-glucosidase inhibitory, and tyrosinase inhibitory activities. The results revealed moderate cytotoxic effects against MCF-7 cells, A549 cells, and HeLa cells, while four compounds showed no activity in any of the cell lines tested. Cycloart-25-ene-3, 24-diol exhibited more potent antioxidant activity and tyrosinase inhibitory properties than the positive control (ascorbic acid and kojic acid). Meanwhile, baccatin showed a good inhibitory effect on the α-glucosidase. In the in silico study, molecular docking simulations were conducted to evaluate the interactions of cycloart-25-ene-3β, 24-diol and baccatin with selected proteins associated with antioxidant, tyrosinase, α-glucosidase, and cancer-related pathways relevant to the studied cell lines. The binding affinities and potential ligand-binding sites were analyzed to provide insights into their possible mechanisms of action.