Antioxidant activity of peptide fractions of capelin protein hydrolysates

Four peptide fractions were separated from protein hydrolysates of capelin (Mallotus villosus) using Sephadex G-10 gel filtration column chromatography. Antioxidant activity of each fraction was determined in a β-carotene-linoleate model system. One isolated fraction possessed a notable antioxidant activity, another two had a weak efficacy while the fourth exerted a prooxidant effect. Two-dimensional thin layer chromatography (TLC) of isolated fractions gave spots with both antioxidant and prooxidant activities. Two prooxidant compounds were separated from the hydrolysate by preparative TLC using silica gel plates. One compound exhibited a maximum absorption at 254 nm while the other absorbed at 260 nm.