Abstract

--- - "Background: Chagas disease is caused by the protozoan parasite Trypanosoma cruzi. This illness is found mainly in 21 Latin American countries and an estimated 8 million people are infected worldwide. The unsatisfactory chemotherapy provokes severe toxicity and resistant strains. Medicinal plants constitute a promising source of new drugs and remedies against all kinds of disorders, mainly infectious diseases arousing interest worldwide." - "Objective: The aim of this study is the isolation, structural identification and evaluation of the trypanocidal activity of samples present in the Excoecaria lucida Sw. leaves." - "Methods: Total extract (TE) of E. lucida Sw. leaves was obtained by ethanol extract therefore fractionated sequentially with hexane, ethyl acetate and n-butanol, to obtain three phases: Hex, EA and But, respectively. Ellagic acid (EL1) was purified from both EA and But phases, while EL2; a 1:1 stigmasterol-3-O-beta-D-glucopyranoside plus sitosterol-3-O-beta-D-glucopyranoside mixture was obtained from the Hex phase. Activity assays were performed using bloodstream and intracellular forms of T. cruzi and cytotoxicity assays using L929 fibroblasts." - "Results: The EL1 and EL2 samples were more active against bloodstream trypomastigote forms with EC50 of 53.0 +/- 3.6 and 58.2 +/- 29.0 mu g/mL, respectively; at 100 mu g/mL. These samples also showed 70% of inhibition of L929 cells infection. Toxicity assays demonstrated that after 96 h of treatment only the fractions Hex and EA presented detectable cytotoxicity." - "Conclusion: Ellagic acid, stigmasterol-3-O-beta-D-glucopyranoside and sitosterol-3-O-beta-D-glucopyranoside are reported for the first time in E. lucida Sw. leaves as well as their biological activity studies supporting further investigations for Chagas disease treatment."