Investigation of the n-hexane extract of Melodorum fruticosum stem

Introduction: Melodorum fruticosum is distributed widely in ASEAN countries. Although this species has been used in folk medicine to cure some diseases, its chemical constituents and biological activity have not been systematically studied. This paper reports the isolation and structural elucidation of seven compounds from the n-hexane extract as well as their cytotoxicity against Jurkat and MCF-7-cell lines. Method: Dried powder of Melodorum fruticosum stem was macerated in ethanol at room temperature to prepare the crude extract. This crude was separated into n-hexane, ethyl acetate, and the remaining aqueous extracts by the liquid‒liquid partition method. Then, the organic compounds were isolated by chromatographic methods and chemically structurally elucidated by modern spectroscopic techniques. Cytotoxicity assays were performed using the sulforhodamine B method (SBR assay). Results: The n-hexane extract showed potential activity against the MCF-7-cell line with an IC50 value of 14.37 ± 3.18 µg/mL. From this extract, seven compounds consisting of techtochrysin (1), pinostrobin (2), flavokawin B (3), 2ʹ-hydroxy-3ʹ,4ʹ,6ʹ-trimethoxychalcone (4), 2ʹ-hydroxy-4ʹ,5ʹ,6ʹ-trimethoxychalcone (5), stigmast-4-ene-3-one (6), and lupeol (7) were isolated and chemically elucidated. Conclusion: It is necessary to continue to isolate and perform a bioassay of organic compounds from this extract to determine the bioactive components.