Evaluation of antioxidant activities from various extracts of Dragon fruit peels using DPPH, ABTS assays and correlation with phenolic, flavonoid, carotenoid content

Abstract

The antioxidant capacities from various extracts of dragon fruit peels were conducted by DPPH (2.2-diphenyl-1- picrylhydrazyl) and ABTS (2-2’-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) assays. Sample WH2 (ethyl acetate peels extract of white dragon fruit) had the highest DPPH scavenging capacity (53.87 %) and the highest ABTS capacity (72.47 %). Sample HB2 (ethyl acetate peels extract of hybrid dragon fruit) contained the highest total flavonoid (9.85 g QE/100 g), the highest phenolic contents (4.55 g GAE/100 g) for SR3 (ethanolic peels extract of super red dragon fruit), while the highest carotenoid 1.51 g BET/100 g was given by SR1 (n-hexane peels extract of super red dragon fruit) and WH1 (n-hexane peels extract of white dragon fruit). The total phenolic and total flavonoid content in sample WH (white dragon fruit peels extract) had positively high correlation with its DPPH and ABTS scavenging capacities. The total carotenoid of three dragon fruit peels extracts had no correlation with DPPH and ABTS scavenging activities. DPPH scavenging capacities in hybrid dragon fruit peels extract had positively high correlation with their ABTS scavenging activities.