Biological activity of the crude extract and several fractions obtained from Piper regnellii var. pallescens was assessed on Leishmania amazonensis. This study included the extraction process and bioassay-guided fractionation by the adsorption chromatography method. A progressive increase in the antileishmanial effect was observed in the course of the purification process. The hydroalcoholic extract water soluble (EBA) had a 50% inhibitory concentration (IC50) at 167 µg/mL whereas the hydroalcoholic extract acetate soluble (EBAcOEt) showed an IC50 of 30 µg/mL against the growth of promastigote forms after 48 h of culturing. The hexan fraction (FHex) showed an antileishmanial activity greater than EBAcOEt with IC50 at 21.5 µg/mL. Analysis of cytotoxicity indicated that the toxic concentrations of the EBA, EBAcOEt, and fractions were higher for J774G8 macrophages than for the protozoans.
Piper regnellii; Leishmania amazonensis; pariparoba; antileishmanial activity; promastigote