Caracterização de substâncias fenólicas de resíduos de frutos amazônicos e avaliação para o uso biotecnológico

Abstract

The use of natural products has increased in recent years because the biological activities related to its chemical composition. However, an obstacle to research is the amount of raw material available for large-scale production. Parallel to this, the consumption of Amazonian fruits has gained space in national and international markets and waste from pulp industries are growing proportionally. It appears that little is known about the chemical composition of these products generated and the biological activity of its extracts may have, which are usually discarded in large quantities, resulting in environmental and economic problems. In the present study we analyzed the composition of phenolic extracts of 19 fruits Amazon, evaluating the antioxidant activity, antimicrobial and enzyme inhibition aiming to biotechnological use. The most promising extracts were analyzed by means of the detection and identification of substances in chromatographic and spectrometric techniques. The samples were kindly provided in different cities of the Amazon northern region (Belem and Coari). Extracts were obtained in ethanol and ethanol: water. The antioxidant, cytotoxic, enzyme, antimicrobial and photoprotective activities were analyzed by different techniques: chemistry and in cell. The extracts analyzed in this study, obtained as by-products of the extraction of the pulp showed up sources of phenolic substances and flavonoidics, besides having significant biological activity with low cytotoxicity, highlighting the acai, bacuri and piquia waste. Piquia shell extracts showed free radicals scavenger capacity of ABTS (CS50: 3.93 ± 0.12 μg.mL-1) and DPPH (CS50: 7.81 ± 0.34 μg.mL-1), in cellular assays, with percentages of 70.69 ± 2.77%, 79.89 ± 6.50% and 79.48 ± 8.6% for shell, pulp and seed extracts, respectively, low cytotoxicity in human fibroblasts, but high at tumor strains, and also a high anti-inflammatory potential observed by the inhibition of nitric oxide production. Different extracts of the açaí (Euterpe oleracea and Euterpe precatoria) and bacuri extracts (exocarp and mesocarp of the Platonia insignis) have been optimized on the methodology and the best solvent extraction. The extracts obtained by cold and hot maceration with ethanol showed most efficient than ultrasound method. Methodologies analysed showed different proportions of the substances, but the same profile. The characterization of the extracts was performed by mass spectrometry using two-dimensional techniques, DESI ionization and HPLC. The extract of E. oleracea and E. precatoria seeds presented different profiles than is commonly reported to the pulp, highlighting the presence of procyanidins, flavonoids and phenolic as crisoeirol, caffeic and coumaric acid. More than 50 ions were detected in each of the extracts. P. insignis mesocarp was 71, which detects the presence of ions flavonoids, isoflavones and procyanidins. In extracts of Caryocar villosum shells were detected and quantified the presence of ellagic acid (1873.63 ± 63.12 μg.g-1) and gallic acid (1712.62 ± 56.79 μg.g-1) as the compounds major. This study opens the possibility of value adding to what is considered waste due to the chemical composition and biological activities found, thereby reducing environmental pollution by waste and contributing to the sustainable use of Amazonian raw materials.