Evaluation of antiparasitic activity of hydroethanolic extracts from root, stem and leaf of Bixa orellana L. ON Leishmania amazonensis samples doi: http://dx.doi.org/10.5892/ruvrv.2012.102.384391

Hydroethanolic extracts of Bixa orellana L. were shown to present antimicrobial activity. In this sense and for the purpose of obtaining data about the therapeutic alternatives in leishmaniases treatment, this study has evaluated the anti-parasitic activity of hydroethanolic extracts from root, stem and leaf of B. orellana L. on Leishmania amazonensis (M2269) samples. These hydroethanolic extracts were added to L. amazonensis cultures in exponential-phase of growth in concentrations ranging from 0.12 to 2.5 mg/mL. The evaluation, by smears analyses (counting, availability and mobility), and by Giemsa staining method (presence of cytoplasmic granules, nuclear structure and kinetoplast), was carried out 72 hours after the incubation at 24ºC by comparing the results obtained to the control. It was observed by the IC50 calculation that the leaf extract (0.14 mg/mL) presented the highest activity, followed by the stem extract (0.21 mg/mL) and the root extract (0.44 mg/mL). Mobility was observed in the smears analyses at concentrations lower than 1.0; 0.75 and 1.5 mg/mL for the root, leaf and stem, respectively. In concentrations higher than 0.25 mg/mL, all extracts presented antiparasitic activity, evidenced by the presence of cytoplasmic granules on L. amazonensis cultures