Antiparasitic activity and characterization of lignans from the ethanolic extract of zanthoxylum monogynum A. St-Hil. leaves

Abstract

Ethanolic extract from the leaves of Zanthoxylum monogynum A. St-Hil (Rutaceae) was fractionated by liquid-liquid partition and by column adsorption chromatography, resulting in the characterization of the lignans savinin, cubebin, 9R- and 9S-3,4-dimethoxyl-3,4-methylenedioxycubebin, and hinokinin, which have several biological activities already described in the literature. The structural identification of these metabolites was made by GC-MS and 1D and 2D NMR analysis. The extract was also tested for its activity against the parasite Trypanosoma cruzi, which causes Chagas disease, that has high incidence in individuals of the poorest regions of Brazil. The antiparasitic analysis of the extract against the epimastigote form of strains Y (domestic cycle) and Dm28c (wild and domestic cycle) presented IC50 results of 69.03 μg.mL-1 and 88.75 μg.mL-1, respectively, considered satisfactory. In order to propose a possible mechanism of action for the extract lethality, a gel zymography test was performed with peptidases extracted from the parasite. Results showed that the extract was able to inhibit migration of peptidases, which are essential for its life cycle. Thus, Z. monogynum leaves extract presents a promising potential for use in the treatment of Chagas disease.