Abstract

Trichomoniasis, most common non-viral sexually transmitted infection worldwide, is produced by protozoan Trichomonas vaginalis. The therapy of choice is metronidazole (MTZ). The drug has undesirable side effects, which may result in treatment discontinuation, leading to further spread of infection and emergence of resistant strains. This feature highlights the importance of studying new trichomonicidal substances. In this context, the importance of plants in relation to the research of new drugs is undeniable. The genus Maytenus, distributed throughout Brazil, is the largest of family Celastraceae, including about 80 recognized species with different biological activities. Therefore, the trichomonicidal activity of MTZ and extracts obtained from Maytenus robusta leaves and Maytenus imbricata roots on the JT strain of T. vaginalis, sensitive (JT) and resistant (JTR) to MTZ was investigated. Sample of T. vaginalis trophozoites were associated with extracts in 6 increasing concentrations ranging from 0.43 to 13.76 μg/ml. The solid that precipitated from the hexane/ethyl ether - 1:1 extract (SEH), obtained from M. imbricata roots proved to be active. This extract also impacted the viability of trophozoites of both strains, with IC₅₀ value surprisingly low (1.09 µg/ml for JT and 1.57 µg/ml for JTR) signaling towards a promising candidate for phytotherapy or for isolation of substance with trichomonicidal activity.

Key words: Maytenus spp, metronidazole, Trichomonas vaginalis.