Produção de extratos enriquecidos com flavonoides a partir de co-produtos da elaboração de suco de uva

Abstract

With increasing population and industrial production growth, there is an increasing amount of waste coming from these transformations. The focus of this study will be on the co-products of the winemaking process, known as grape marc. Every year 60 million tons of grape are produced, 80% of which are used in the winemaking process, generating tons of underutilized organic co-products. This is characterized by its high concentrations of phenolic compounds which can be reused as antioxidants. Thus, the main goal of this project was to present the influence of different extraction methods on chemical composition and antioxidant activity of these extracts/fractions. For this, the extractions were performed by microwave, ultrasound and liquid-liquid, with different polarities solvents (ethanol, water, methanol, hexane, chloroform and ethyl acetate). Moreover, the extract was fractionated with the aid of an open column using silica as stationary phase and different polarities solvents as mobile phase. The chemical characterization was performed by High Performance Liquid Chromatography with UV-Vis detector (CLAE) and High Resolution Mass Spectrometry (HRMS). Among the main compounds identified are phenolics such as rutin, gallic acid, catechin, and some carboxylates such as linoleic acid and stearic acid. In the extracted extractions we can identify that the ethanol solvent, in all extraction methods, obtained better results regarding the qualification and quantification of chemical compounds in analysis with HPLC-UV. The evaluation of antioxidant capacity was carried out using the 2,2-diphenyl-1-picrylhydrazyl (DPPH •) method. The data obtained by microwave extraction showed a higher percentage of scanning (2,44%±36,64), when the solvent used was ethanol. In the extraction by sonography, the highest values 2,07%±74,22 were observed using ethyl acetate. In the liquid-liquid extraction the highest percentage of sweep (0,61±33,62) was observed for the solvent ethyl acetate. In general, the extracts obtained by extraction with microwaves presented higher levels of phenolic compounds (0,04±13,18 a 6,02mg±107,03 GAE/100g). The results obtained in this project indicate that this co-product can be better utilized for the application as a source of functional ingredients, as food supplements or in the cosmetic industry, because they contain important compounds (sic).