Fractionation and purification of antioxidant peptides from abalone viscera by a combination of Sephadex G‐15 and Toyopearl HW‐40F chromatography

Summary Abalone viscera, a protein‐rich by‐products from the abalone processing industry, are normally discarded as wastes. In the present study, four different proteases were used to hydrolyse abalone viscera to prepare high‐activity antioxidant peptides, and their hydrolysis effects were compared. Although the hydrolytic abilities of papain and trypsin were inferior to the alcalase and neutrase, their use resulted in significantly ( P < 0.05) higher scavenging activities for DPPH. The hydrolysates mainly consisted of peptides with a molecular weight <3 kDa, and the fractionation was achieved using a combination of Sephadex G‐15 and Toyopearl HW‐40F gel filtration chromatography, which overcomes the disadvantages of traditional membrane separation technology in fractionating peptides with relatively similar molecular weight distribution. The DPPH scavenging activities of the components containing peptides <1 kDa (fractions E) were significantly ( P < 0.01) higher than those containing peptides >1 kDa. The different fractions E were further purified by reversed‐phase high‐performance liquid chromatography, and a total of 16 target peptides, containing 4‐8 amino acids, enriched in hydrophobic amino acids and C‐terminal Arg, with molecular weights ranging from 500 to 850 Da, were identified.