Searching for new leishmanicidal agents, promastigotes forms of L. amazonensis were cultured with the hydroalcoholic extracts obtained from the Tephrosia cinerea (L.) Pers. (Fabaceae), Dichorisandra sp (Commelinaceae), Syzygium jambolanum DC. (Myrtaceae), Julocroton triqueter (Lam.) Didr. var. triqueter (Euphorbiaceae), Passiflora edulis Sims(Passifloraceae), Cecropia sp (Cecropiaceae), Chenopodium ambrosioides L.(Chenopodiaceae), Pedilanhus tithymaloides (L.) Poit (Euphorbiaceae), Peristrophe angustifolia Nees(Acanthaceae) leaves and the aqueous extract obtained from the Orbignya phalerata Mart. (Arecaceae) mesocarp flour. The in vitro assay was performed with promastigotes incubated during 24 hours with 31.3, 62.5, 125.0, 250.0 and 500.0 µg/mL of each extract. Then the inhibitory concentration of the parasite growth (IC50) was determined. The effectiveness of J. triqueter, Dichorisandra sp and T. cinerea hydroalcoholic extracts to induce promastigotes death was intense since the IC50 were 29.5; 32.9 and 43.6 µg/mL, respectively. P. edulis, C. ambrosioides and S. jambolanum extracts had moderated effectiveness since the IC50 were 150.1; 151.9 and 166.6 µg/mL, respectively. P. tithymaloides and O. phalerata extracts showed a low efficacy in comparison with IC50 >500 µg/mL. Peristrophe angustifolia and Cecropia sp extracts had no leishmanicidal effect. Thus, three of the ten extracts that were tested showed a significant in vitro leishmanicidal activity.
Leishmania amazonensis; leishmanicidal activity; medicinal plants