Antioxidant activity of bovine casein hydrolysates produced by Ficus carica L.-derived proteinase

A Ficus carica L. latex proteinase preparation was investigated for its ability to produce antioxidant hydrolysates/peptides from bovine casein (CN). The Oxygen Radical Absorbance Capacity (ORAC) values for NaCN and β-CN hydrolysates ranged from 0.06 to 0.18, and from 0.51 to 1.19 μmol Trolox equivalents/mg freeze-dried sample, respectively. Gel permeation HPLC showed that the β-CN hydrolysate with a degree of hydrolysis of 21% had 65% of peptide material with a molecular mass <500 Da. The RP-UPLC profiles also indicated that β-CN was substantially hydrolysed during the early stages of hydrolysis. Analysis of the 4 h β-CN hydrolysate by LC-ESI-MS/MS allowed identification of 8 peptide sequences with potential antioxidant properties.