Anti-Mycobacterium tuberculosis activity and cytotoxicity of Calophyllum brasiliense Cambess (Clusiaceae)

Abstract

We evaluated the in vitro anti-Mycobacterium tuberculosis activity and the cytotoxicity of dichloromethane ex- tract and pure compounds from the leaves of Calophyllum brasiliense. Purification of the dichloromethane extract yielded the pure compounds (-) mammea A/BB (1), (-) mammea B/BB (2) and amentoflavone (3). The compound struc-tures were elucidated on the basis of spectroscopic and spectrometric data. The contents of bioactive compounds in the extracts were quantified using high performance liquid chromatography coupled to an ultraviolet detector. The anti-M. tuberculosis activity of the extracts and the pure compounds was evaluated using a resazurin microtitre assay plate. The cytotoxicity assay was performed in J774G.8 macrophages using the 3-(4,5-dimethyl thiazol-2-yl)- 2,5-diphenyl tetrazolium bromide colourimetric method. The quantification of the dichloromethane extract showed and (2) at concentrations of 31.86 ± 2.6 and 8.24 ± 1.1 μg/mg of extract, respectively. The dichloromethane and aqueous extracts showed anti-M. tuberculosis H37Rv activity of 62.5 and 125 μg/mL, respectively. Coumarins (1) and showed minimal inhibitory concentration ranges of 31.2 and 62.5 μg/mL against M. tuberculosis H37Rv and clini- cal isolates. Compound (3) showed no activity against M. tuberculosis H37Rv. The selectivity index ranged from 0.59- 1.06. We report the activity of the extracts and coumarins from the leaves of C. brasiliense against M. tuberculosis.