CARACTERIZAÇÃO QUÍMICA E ATIVIDADE ANTIOXIDANTE DE EXTRATO BRUTO DE MICRORGANISMOS FOTOSSINTETIZANTES DO “PARQUE NACIONAL DA CHAPADA DAS MESAS”, CERRADO BRASILEIRO

Abstract

Cyanobacteria and microalgae are photosynthetic microorganisms, which produce bioactive compounds such as carotenoids, flavonoids, and fatty acids, of importance for the pharmaceutical, cosmetic, food and biofuel industries. This work aimed to investigate the bioactive potential of the extracts of microalgae Chlorella sp. (GBBB06), cyanobacteria Nostoc sp. (GBBB01) and Synechococcus sp. (GBBB07), collected in the Chapada das Mesas National Park, in the Cerrado of Maranhão. Methanolic extracts of the studied samples were performed, to then chemically characterize using chromatographic techniques such as thin layer chromatography, high performance liquid chromatography coupled to the diode array detector, and gas chromatography coupled to the mass spectrometer, and to assess the antioxidant potential the DPPH • and ABTS•+ test was performed. Through liquid chromatography, peaks with characteristic wavelengths of carotenoids were identified in the sample of Chlorella sp. (GBBB06) and characteristic peaks of chlorophylls in all studied samples. In gas chromatography, metabolites such as fatty acids, alcohols and nitrogen compounds were identified. Among the identified compounds, those that present the greatest abundance in the chromatogram are phytol, glycerol, acetic acid, benzoic acid and N, N-dimethyl-acetamide. In the evaluation of the antioxidant potential, the samples had the capacity to sequester 12% (Nostoc sp.), 20% (Chlorella sp.) And 25% (Synechococcus sp.), of 2,2 Diphenyl-1-picrylhydrazyl in the concentration of the extract 0.675 mg / mL, showing no increase in activity at the highest concentrations of the extract. The results with the radical ABTS•+ showed high antioxidant potential of the samples, with the ability to sequester ABTS•+ in 60% (Chlorella sp.) 70% (Synechococcus sp.) and 70% (Nostoc sp). These results demonstrated that Chlorella sp. Nostoc sp. and Synechococcus sp. they have a chemical composition rich in secondary bioactive metabolites with potential biotechnological application, and thus, these extracts represent an alternative for economically exploring the Brazilian Cerrado in a sustainable manner.