Enzymatic preparation and characterization of iron-chelating peptides from anchovy (Engraulis japonicus) muscle protein

Anchovy (Engraulis japonicus) is a small, low-value, marine fish and is mainly targeted for nonfood uses. In this study, the enzymatic preparation and properties of iron-chelating peptides from anchovy muscle protein were evaluated. The results showed that the trypsin hydrolysate possessed the greatest iron-chelating activity, and the iron-chelating activity was governed by the degree of hydrolysis (DH) and the iron-chelating conditions (temperature and pH). Among the gel-filtration fractions, Fraction 1 and Fraction 3 exhibited higher iron-chelating activities, and the IC50 values were 0.048 and 0.086mg/ml, respectively. A novo trypsin-resistant, large-molecular-weight, iron-chelating fraction was purified from Fraction 1, and was identified to be homologous with the conserved domain of the coiled-coil myosin heavy-chain tail region. Fraction 3 yielded two oligopeptides, Ser-(Gly)7-Leu-Gly-Ser-(Gly)2-Ser-Ile-Arg and Ile-(Glu)2-Leu-(Glu)3-Ile-Glu-Ala-Glu-Arg. We thus conclude that anchovy might be beneficial as a bioresource to produce anti-anemia compounds which can be used in functional foods. ► Anchovy is a promising resource for enzymatic production of iron-chelating peptides. ► The iron-chelating ability of peptides is dependent on pH and temperature. ► Two oligopeptides R.SGGGGGGGLGSGGSIR.S and R.IEELEEEIEAER.A were identified.