BIOACTIVE COMPOUNDS AND ANTIOXIDANT CAPACITY OF AÇAÍ SEED EXTRACT (Euterpe oleraceae Mart.) OBTAINED WITH EUTECTIC SOLVENTS

Açaí seeds (Euterpe oleraceae Mart.) are lignocellulosic residues that can be reused for the recovery of bioactive compounds through chemical pretreatment. In this context, eutectic solvents are innovative biodegradable liquids with high extractive potential, formed by the fusion of heated compounds in specific molar proportions. Thus, this work aimed to determine the total phenolic compounds, total flavonoids and antioxidant capacity of açaí seed extract, obtained from chemical pretreatment with eutectic solvents. The açaí seeds were collected in the city of Belém (Pará, Brazil), sanitized, dried in an oven and ground in a knife mill. The eutectic solvents were synthesized in Erlenmeyer flasks heated in a shaker (60 °C/200 rpm), using choline chloride and citric acid (ClCo:AC) or choline chloride and oxalic acid (ClCo:AO), in a molar ratio of 1:1. The chemical pre-treatment was carried out via central composite experimental design of type 2², varying the solids load (5-17% w/V) and the amount of water added to the solvent (30-50g/100g). The residue was mixed with the diluted solvent and subjected to a vertical autoclave cycle (60 min/121 °C).  Then, the extracts were filtered and stored. The total phenolic compounds were quantified by the Folin-Ciocalteu method and the total flavonoids by complexation with aluminum, while the antioxidant capacity was determined by the DPPH and FRAP methods