ANTIOXIDANT ACTIVITY OF LYCHEE PEEL AND SEED FLOUR BLEND

Litchi chinensis Sonn. (also known as Chinese cherry, lychee) has a wide variety of bioactive compounds in the seeds, pulp, and peel, mainly flavonoids, anthocyanins, and phenolic acids, with proven antioxidant activity. The present study aimed to evaluate the antioxidant activity of the lychee peel and seed flour blend. For the formulation of the hydroalcoholic extract, 1.5 g of lychee peel flour and 1.5 g of lychee seed flour were used for a volume of 30 mL of 70% alcohol. The material was kept in amber glass for seven days, and shaken twice a day. On the seventh day, the extract was filtered and kept in the amber glass until the moment of the analysis. The ABTS+, DPPH*, β-Carotene/Linoleic Acid, and Phosphomolybdenum Complex assays were used to determine the antioxidant activity. The results of the antioxidant activity determined by the ABTS+ radical, DPPH*, and Beta-Carotene/Linoleic Acid system assays were expressed in percent inhibition and g ascorbic acid equivalent (AAE g-1) for the phosphomolybdenum complex methodology. The results showed a % radical inhibition of 97.94 ± 0.66 and 95.58 ± 0.35 for the ABTS+ and DPPH* assay, respectively. For the β-Carotene/Linoleic acid system, a % inhibition of oxidation of 47.22 ± 2.80 was observed. Finally, the antioxidant activity of Phosphomolybdenum Complex was 10.57 ± 0.17 g AAE g-1. Antioxidant activity can be measured by different methods that are based on different principles. No method is superior to another, because everything depends on the physicochemical characteristics of each sample being analyzed. Therefore, it is concluded that the lychee peel and seed flour blend presents antioxidant activity proven by the different methodologies used.