Pré-purificação do extrato clorofórmico de cará-moela (Dioscorea bulbifera) e avaliação de potencial atividade antioxidante

Abstract

Dioscorea bulbifera is a plant of African origin known as cara-moela, which bears bulb-shaped fruits (tubers), using popular medicine to treat diseases such as goiter, stomach cancer, among others. of panc (non-conventional food plants). Vegetables, in general, have a complex chemical composition and, in order to study the potential components by biological activities, it is necessary to separate and purify crude extracts through chromatographic methods. The separation and purification of bioactive compounds can be performed through bioguided fractionation, whose objective is to concentrate the bioactivity in the purified compounds, thus facilitating the study of bioactive substances. In this context, the objective of this work was to carry out the bioguided solid-liquid fractionation, from the crude extract of D. bulbifera tubers, using as tools for bioactivity evaluation, observation methods and antioxidant activity analysis. The solid-liquid fractionation was carried out from the lyophilized chloroform extract, resulting from the pre-purification through liquid-liquid partition of the crude extract, using a polarity gradient (chloroform, ethyl acetate and methanol). This extract, in addition to one of its fractions, were evaluated for antioxidant capacity using the in vitro methods of FRAP, DPPH •, ABTS • + and Total Phenolics. The EC fractionation resulted in 120 fractions that were grouped by similarity into 20 fractions, where one of the fractions was passed to evaluate its antioxidant potential. The results obtained for the EC antioxidant activity were superior to the required fraction, with the exception of the iron reduction capacity method (FRAP) where the F14 fraction presented results of 4114 ± 19.2 μmol ET g-1 while for the EC os results obtained were 2557 ± 8.79 μmol ETg-1.