Biflavonoids with cytotoxic and antibacterial activity from Ochna macrocalyx
Tang, S, Bremner, P, Kortenkamp, A, Schlage, C, Gray, AI, Gibbons, S & Heinrich, M 2003, 'Biflavonoids with cytotoxic and antibacterial activity from Ochna macrocalyx', Planta Medica, vol. 69, no. 3, pp. 247-253.
Published version available from:
Six biflavonoid and related compounds were isolated from the ethanolic extract of Ochna macrocalyx bark. One is a new compound, the isoflavanone dimer dehydroxyhexaspermone C (1). Previously isolated compounds obtained from the bark are biisoflavonoid hexaspermone C (2), tetrahydrofuran derivative ochnone (3), furobenzopyran derivative cordigol (4), and biflavonoids calodenin B (5) and dihydrocalodenin B (6). Although 3 has already been isolated, its spectral data are presented here for the first time. Isolated compounds were tested for cytotoxic activity on MCF-7 breast cancer cells using the MTF reduction assay method. Compound 5 showed cytotoxic activity (7 Â± 0.5 Î¼M) and 6 showed moderate cytotoxicity (35 Â± 7 Î¼M). In antibacterial assays performed using three strains of multi-drug resistant (mdr) Staphylococcus aureus (RN4220, XU212 and SA-1199-B) compounds 5 and in particular 6 showed strong antibacterial activity (MlCs 5:64, 8, 16 Î¼g/mL 6:8, 8, 8 Î¼g/mL, respectively). The ethanolic extract of the bark also showed NF-ÎºB inhibitory activity.