Identification and Characterization of Antioxidant Peptides from Enzymatic Hydrolysates of Duck Meat

The objective of this study was to prepare antioxidant peptides from duck meat hydrolysate (DMH) using Protamex. The DPPH center dot scavenging activity, hydroxyl radical ((OH)-O-center dot) scavenging activity, and Fe2+-chelating ability of DMH were investigated. DMH was separated into three groups, MWCO-1 (69.57%), MWCO-2 (9.53%), and MWCO-3 (8.21%), by ultrafiltration. MWCO-3 exhibited the highest DPPH center dot scavenging activity (83.17 +/- 0.73%) and was subsequently fractionated by using gel filtration chromatography to obtain fraction B (40.90%). Fraction B5 (6.71%) obtained from ion exchange chromatography exhibited the highest DPPH center dot scavenging activity (93.63 +/- 0.13%) and contained seven peptides which were characterized by LC-MS/MS. Among these peptides, LQAEVEELRAALE showed the highest DPPH center dot scavenging activity (93.36 +/- 0.53%) and Fe2+-chelating ability (87.13 +/- 0.47%) and IEDPFDQDDWGAWKK exhibited the highest (OH)-O-center dot scavenging activity (46.51 +/- 0.16%). The results presented here indicated that DMH could serve as a suitable source of antioxidant peptides.