Extraction of phenolic compounds and anthocyanins from juçara (Euterpe edulis Mart.) residues using pressurized liquids and supercritical fluids

Abstract

Extracts rich in phenolic compounds and anthocyanins from industrial residue of juçara (Euterpe edulis Mart.) were obtained using different high pressure extraction processes. Pressurized Liquid Extraction (PLE) was evaluated at 10MPa and 40, 60 and 80°C using ethanol, water, acidified mixture of ethanol+water and acidified water as solvents. The best solvent in PLE was selected as cosolvent for supercritical fluid extraction (SFE) with CO2. Among the PLE extracts, the highest antioxidant activity and concentration of phenolics were obtained with the acidified mixture of ethanol+water at 80°C and the highest anthocyanin content was achieved with acidified water at 40°C. Based on the PLE results, a two-stage sequential extraction strategy was adopted, producing an extract rich in anthocyanins and another rich in heat resistant phenolic compounds. The selected cosolvent (acidified mixture ethanol+water) for SFE improved significantly the anthocyanin content. Four anthocyanins were identified and quantified by UPLC.