Composição química, avaliação do potencial antioxidante e toxicidade das folhas de Acrocomia aculeata (Jacq) Lodd. ex. Mart

Abstract

Brazilian biodiversity represents a rich source of natural chemical components that can reveal potentially active substances for various purposes. The pharmacological importance of plants is related to their chemical composition, which provides important therapeutic properties, such as antioxidant activity. Acrocomia aculeata is a native palm of the Brazilian Cerrado, its pulp is rich in lauric acid, β carotene, and its almond in oleic acid. Its medicinal use is described in the treatment of respiratory diseases, lowering blood glucose and serum cholesterol levels, besides having anti-inflammatory and laxative properties, being widely used in the cosmetic, food and biofuel industry. Although fruits are widely used and known, little is known about the leaves, because of this, this study aimed to evaluate the chemical composition, antioxidant activity and toxicity of A. aculeata leaves. Extracts with three different solvents were produced: water (EA-Aa), ethanol (EE-Aa) and methanol (EM-Aa). The extracts were chemically characterized by the determination of phenolic compounds, flavonoids and tannins, besides chromatographic analysis, followed by the evaluation of the antioxidant activity of the extracts by free radical capture methods, DPPH and ABTS. EE-Aa and EM-Aa presented higher amounts of secondary metabolites evaluated and better free radical capture results. However, in the protection assay against oxidative hemolysis and evaluation of lipid peroxidation in AAPH-induced erythrocytes, EA-Aa showed greater effect than the other extracts evaluated. Thus, we continue the trials to determine the protective effect of EA-Aa against AAPH-induced protein oxidation, DNA fragmentation, and H2O2-induced EROS generation. Increased levels of Sirt-1, catalase and ERK and Nrf2 activation were observed in EA-Aa-treated Cos-7, which was also observed in C. elegans nematodes, which were more viable when treated with EA-Aa. and induced with Juglone. The low toxicity of EA-Aa has also been proven in the various experimental models tested. Taken together, the leaf extracts of A. aculeta presented typical chemical composition to those of plants, but the diversity of compounds presented in EA-Aa is probably involved in their low toxicity, and their relevant antioxidant potential evaluated in different biomolecules and also in Cos- 7 and C. elegans, is probably related to the activation of the Sirt1 / Nrf2 pathway. Thus, the results support future uses of EA-Aa in the treatment of diseases related to oxidative stress.