Extração de antocianinas do açaí (Euterpe oleracea) em sistemas aquosos bifásicos formados por etanol e sulfato de amônio

Abstract

Euterpe oleracea is a plant species that occurs naturally in the Amazon region, known as açaí. Its fruit is considered a functional food due to the high content of phenolic compounds, mainly anthocyanins, which gives the fruit high antioxidant power. In addition, it presents high nutritional value presenting in its composition fibers, proteins, vitamins and minerals. In this study the technique of extraction by Aqueous Two-Phase System (ATPS) was applied to the study of the partition of the anthocyanins present in the aqueous extract of açaí. The alcoholic extract of açaí was used to study the stability of anthocyanins in different solutions of salts and alcohol, where the extract had 718.32 mg/L of anthocyanins. ATPS were prepared with ammonium sulfate, ethanol and water at 25 and 35 ° C. In the process of extraction of anthocyanin by ATPS was verified the effect of pH, temperature and time of extraction. The best anthocyanin extraction condition was pH 3.4 at 33 °C for 30 min. The best partition coefficient obtained was 2.70, indicating the affinity of the compound studied for the top phase of ATPS. The extraction process used in this study was more efficient than the conventionally used analytical quantification technique for anthocyanin extraction.