Free radical-scavenging capacity and HPLC-DAD screening of phenolic compounds from pulp and seed of Syzygium claviflorum fruit.

Recently, the demand for natural antioxidants in food manufacturing has increased significantly because of the possible toxicity of synthetic antioxidants. In this context, this research work was performed to evaluate the potentiality of seed (seed with kernel) and pulp (edible portion: pulp with peel) of Syzygium claviflorum to serve as natural antioxidants. The free radical scavenging capacity of S. claviflorum extracts was evaluated by 2,2′-azino-bis (3-ethylbenzothiazolin)-6-sulfonic acid (ABTS), and 1,1-Diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assays. In DPPH and ABTS free radical scavenging assays seed extract demonstrated significantly (p < 0.05) higher free radical scavenging and antioxidant properties compared to pulp extract. Free radical-scavenging capacity of S. claviflorum extract from seed was comparable with natural and artificial antioxidants like ascorbic acid and butylated hydroxytoluene (BHT). In ABTS assays, seed extract of S. claviflorum (IC₅₀=3.80±0.02 μg/ml) displayed higher free radical-scavenging capacity than the ascorbic acid (IC₅₀=10.23±0.06 μg/ml)...