Antioxidant activity and phenol content and flavonoids total of the Hymenaea stigonocarpa Mart and Hymenaea courbaril L

Abstract

Hymenaea stigonocarpa Mart. and Hymenaea courbaril L. var. stilbocarpa (Hayne), family Leguminosae, are medicinal species commonly found in the Brazil, they are widely used in tea form to treat several diseases such as gastric pain, ulcers, diarrhoea and inflammation. The beneficial effects of these species are correlated with the presence of secondary metabolites. In this context, the aim of the present work was to investigate antioxidant activity and the phenolic compounds and flavonoids in methanolic and hydroethanolic extracts from leaf, rind, seeds and pulp of H. courbaril Mart. and H. stigonocarpa L. fruits. All extracts were obtained by maceration and concentrated under reduced pressure in rotary evaporator. The method used to evaluate the antioxidant activity was the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method and the antioxidant activity of the extracts was calculated as the EC50 concentration. The total phenolic content of the extract was determined by the Folin-Ciocalteu test. Quantification was carried out on the basis of the standard curve of commercial gallic acid, and the concentration of total phenolic compounds was expressed as mg of gallic acid equivalents (GAE)/g of dry extract. The flavonoids content was determined by the ultraviolet-visible spectrometry method and calculated from the standard curve of rutin and the results were expressed as mg of rutin equivalents (RE)/g of dry extract. All determinations were performed in triplicate. Among the various extracts evaluated, the hydroethanolic extract of the seed of H. courbaril L. presented the maximum contents of total phenolics and total flavonoids (464,34 mg GAE/g of dry extract and 442,25 mg RE/g of dry extract, respectively). This extract also promoted high DPPH scavenging activity (EC50 = 149,43 (µg/mL). According to the results obtained, extracts with higher antioxidant capacity also has higher total phenolic and flavonoids.