ACID-MEDIATED ANTHOCYANIN EXTRACTION AT DIFFERENT pH AS A STRATEGY FOR THE USE OF THE BARK RESIDUE OF ACID-MEDIATED ANTHOCYANIN EXTRACTION AT DIFFERENT pH AS A STRATEGY FOR THE USE OF THE BARK RESIDUE OF Oenocarpus bacaba MART. (BACABA) MART. (BACABA)

Oenocarpus bacaba Mart., known as bacaba, is an Amazonian fruit of high nutritional and functional value rich in flavonoids and anthocyanins, found both in the pulp and in the peels, which in turn are discarded as waste during processing. In this context, peels represent a promising and abundant source of anthocyanins, making residues targets of interest with regard to applications for the development of functional foods and nutraceuticals. The objective of this study was to evaluate the influence of acidification of the extractive medium using different acids (hydrochloric, sulfuric and acetic) and pH ranges (1-5) on the yield and antioxidant activity of anthocyanins from bacaba peel. For this, the peels were subjected to Ultrasound-assisted extraction, for two hours, in 70 % ethanol (1:10, w/v) acidified with pH ranging from 1-5 with the different acids, then the extracts were concentrated in a rotary evaporator (40 °C) and analyzed for anthocyanin content, through the differential pH method, and antioxidant capacity, through the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic) (ABTS) assays. The results showed that hydrochloric acid at pH 2 provided the highest yield of anthocyanins expressed in cyanidin-3-glycoside equivalents per gram of extract (10,094 μg Eq