Cytotoxic constituents from dendrobium brymerianum

Abstract

Phytochemical study of the methanol extract from Dendrobium brymerianum (Orchidaceae) led to the isolation of eight compounds, which could be classified into 3 groups, consist of bibenzyls (moscatilin, gigantol and tristin), phenanthrenes (flavathrinin and lusianthridin) and fluorenones (nobilone, dendroflorin and denchrysan B). Their structure determinations were carried out by analysis of their spectroscopic data (UV, IR, MS 1H NMR and 13C NMR) and comparison with previously reported data. These obtained compounds were evaluated for cytotoxic activity against KB (oral cavity cancer) and H460 (lung cancer) cell lines. The results suggested that, for the KB cells, moscatilin exhibited the strongest cytotoxic effect with an IC50 value of 2.62 μM, whereas flavanthrinin, lusianthridin showed moderate activity (IC50 79.67 and 44.13 μM, respectively), and denchrysan B and tristin showed weak activity (IC50 158.91 and 163.83 μM, respectively). Ellipticine (IC50 5.00 μM) and Doxorubicin (IC50 1.44 μM) were used as a positive control. Moreover, for H460 cells, moscatilin, gigantol, lusianthridin and dendroflorin exhibited potential cytotoxic effect with IC50 values of 674.04, 85.40, 268.60 and 487.60 μM, respectively. These compounds were further investigated for their anti-migration activity. The results indicated that at 48 hr. moscatilin showed the strongest anti-migration effects, followed by dendroflorin, lusianthridin and gigantol.