In vitro antiplasmodial and cytotoxic activity of the stem inner bark of Maytenus guianensis Klotzsch Ex Reissek

Abstract

Species of the Maytenus genus (Celastraceae) are commonly used in folk medicine in the Amazon region against cancer and as an anti-inflammatory agent. Maytenus guianensis, popularly known as “chichuá” or “xixuá”, is a widespread tree in the Amazon rainforest. In this study, we investigated the acetone extract of the inner bark of this species regarding its cytotoxic activity against HepG2 cells and its antiplasmodial activity against the 3D7 strain of Plasmodium falciparum. Cytotoxicity was determined by the colorimetric method (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and the anti-P. falciparum activity was tested using anti-HRPII antibodies in an enzyme-linked immunosorbent assay. In the cytotoxicity assay, no cytotoxic activity was detected in any tested sample, according to the National Institute of Cancer standards. The results of the anti-P. falciparum  test, on the other hand, were promising (values expressed as IC50, in ng.mL-1): 253.02 ± 0.56 for the acetone extract of the inner bark, 292.23 ± 0.83 for the hexane fraction, 292.76 ± 0.51 for the chloroform fraction, 188.37 ± 0.74 for the acetone fraction, 837.04 ± 0.23 for friedelinol, and 950.25 ± 0.46 for 16 β-hydroxyfriedelin. Our results contributed with the chemotaxonomy of the Celastraceae and showed that M. guianensis may be an alternative source of compounds that could be used in prototypes of anti-malaria drugs.