Avaliação da atividade inibitória e antioxidante de óleos essenciais e nanoemulsões sobre Trichomonas vaginalis

Abstract

Trichomonas vaginalis is the flagellate protozoan that causes trichomoniasis, the most common non-viral sexually transmitted infection (STI) in the world. In front of the increased prevalence of metronidazole-resistant infections, the only recognize treatment to trichomoniasis, studies were realized in search of therapeutic alternatives. Natural products biologically active, as essential oil, which constitute a model for synthesizing new drugs, becoming a new therapeutic resource with lower side effects associate to nanotechnology. In this study, was evaluated in vitro the anti-trichomonal activity of free essential oils (EO) and nanostructured of Eucalyptus globulus (eucalyptus), Ocimum basilicum (basil), Cymbopogon flexuosus (lemongrass) and its major compound citral, separated into two experiments. At the first experiment, were tested free EO and nanostructured of eucalyptus, basil and lemongrass in clinical isolate. The MIC observed to lemongrass was 660 μg/mL to free oil 440 μg/ml to nanoemulsion and to basil was 1080 μg/ml either in free or nanostructured form, showing significant antiparasitic activities in 12 and 24 hours exposure, respectively, inhibiting 100% of trophozoites. Also was evaluated through TBARS assay (Thiobarbituric acid reactive substances) antioxidant activity of these oils and nanoemulsions, observing the reduction of lipid peroxidation. At second experiment, was evaluated citral activity against ATCC (30236), showing MIC 100 μM/ml to inhibit 100% of trophozoites in 12 h of incubation and IC50 40 μM/ml (24 h). The nitric oxide (NO) levels was also determined and after 24 h of exposure of parasite to citral showed a significant reduction of NO when compared to control. In front of the results obtained, EO are an alternative to developing of drugs to this STI. Should be considered further studies of these natural products even at free form or associate to nanocarriers, in search to develop a new anti-trichomonal drugs nonnitroimidazole in order to reduce the resistance and the side effects to the treatment of trichomoniasis.