Remarkable Anti-Trichomonas vaginalisActivity of Plants Traditionally Used by the Mbyá-Guarani Indigenous Group in Brazil
Trichomonas vaginalis, a flagellate protozoan, is the causative agent of trichomonosis, the most common nonviral sexually transmitted disease worldwide. Taking into account the increased prevalence of metronidazole-resistant isolates, alternative drugs are essential for the successful treatment. Natural products are the source of most new drugs, and popular wisdom about the use of medicinal plants is a powerful tool in this search. In this study, the activity of 10 medicinal plants extensively used in daily life by Mbyá-Guarani indigenous group was evaluated against seven differentT. vaginalisisolates. Among the aqueous extracts tested,Verbenasp. (Guachu ka'ain Mbyá-Guarani language) andCampomanesia xanthocarpa(Guavirain Mbyá-Guarani language) showed the highest activity againstT. vaginaliswith MIC value of 4.0 mg/mL reaching 100% of efficacy against the parasite. The kinetic growth assays showed that the extracts promoted complete growth abolishment after 4 h of incubation. In addition, the extracts tested did not promote a significant hemolytic activity against human erythrocytes. Our results show for the first time the potential activity ofVerbenasp. andC. xanthocarpaagainstT. vaginalis. In addition, this study demonstrates that indigenous knowledge is an important source of new prototype antiprotozoal agents.