Author(s): Oldoni, Tatiane Luiza Cadorin ; Melo, Priscilla Siqueira ; Massarioli, Adna Prado ; Moreno, Ivani Aparecida Marchetto ; Bezerra, Rosangela Maria Neves ; Rosalen, Pedro Luiz ; Silva, Gil Valdo José da ; Nascimento, Andréa Mendes do ; Alencar, Severino Matias de
Date: 2016
Origin: Oasisbr
Subject(s): Purification; Chromatography; Antioxidant activity; Phenolic compounds
Purification and bioassay-guided fractionation were employed to isolate proanthocyanidins with antioxidant activity from peanut skin (Arachis hypogaea Runner 886). The crude extract was prepared with acetone (60% v/v) and purified using chromatographic methods, including a semipreparative HPLC technique. As a result, two proanthocyanidins were isolated and identified using NMR, epicatechin-(2 b?O?7, 4 b?8)-catechin (proanthocyanidin A1) and epicatechin-(b?2 O?7, 4 b?8)-epicatechin (proanthocyanidin A2). Despite the structural similarity, differences were observed in their antioxidant activity. Proanthocyanidin A1 proved to be more active, with EC50 value for DPPH radical scavenging of 18.25 lg/mL and reduction of Fe3+–TPTZ complex of 7.59 mmol/g, higher than that of synthetic antioxidant BHT. This compound evaluated by ABTS+_ was similar to that of natural quercetin. Therefore, peanut skin is an important source of bioactive compounds that may be used as a mild antioxidant for food preservation.
