Fracionamento bioguiado de folhas de Syzygium malaccense

Abstract

Syzygium malaccense is a plant of Asian origin that has adapted to the climate of the northern, northeastern and southeastern regions of Brazil, used in popular medicine for food and in the treatment of gastrointestinal disorders, inflammation and diabetes. The plants are considered complex matrices of study because, in general, they present a very complex and varied chemical composition. For a complete study of chemical characterization and determination of the compounds responsible for the biological activities of the study material, it is necessary to separate the compounds in order to determine their biological activities. The separation of bioactive substances can be performed from the bioguided fractionation, whose main characteristic is to concentrate the bioactivity in the purified compounds, facilitating and making feasible the study of bioactive substances in complex samples. In this context, the objective of this work was to perform a solid-liquid fractionation bioguided from the extract of S. malaccense leaves collected in the city of Jacupiranga - SP, using the antioxidant activity as a tool for bioactivity. The fractionation was performed from the lyophilized hydroalcoholic extract of the plant using six solvents in increasing order of polarity (hexane, dichloromethane, ethyl acetate, acetone, ethanol and ethanol: water) and the extracts obtained were evaluated for antioxidant capacity from in vitro techniques (DPPH•, ORAC and FRAP), total phenolic compounds and flavonoids, and high performance liquid chromatography (HPLC). The best results for the antioxidant activity were obtained for the fractions with more polar characteristics, such as the fraction in ethanol, which presented the highest capacity of capture of the radical DPPH (3412 μmol ET g-1) and iron reduction by the analysis of FRAP (17173 μmol Fe2+ g-1); the fraction in ethyl acetate, with the greater scavenger capacity of peroxil radicals (4785 μmol ET g-1), and the acetone fraction with total phenolic compounds content of 349.3 mg EAG g-1 and flavonoid content of 581.7 mg EQ g-1, fractions in which the phenolic compounds catechin, myricitrin, quercetin and gallic acid were identified.