The Radical Scavenging Activity of Protein Hydrolysates Prepared from Mercenariamercenaria and Ruditapesphilippinarum

The Mercenaria mercenaria protein hydrolysates (MMPH) and Ruditapes philippinarum protein hydrolysates (RPPH) were prepared by three enzymatic methods, and the radical scavenging activity of the protein hydrolysates was analyzed. The results showed that the protein hydrolysates prepared by the combination of Protamex and Flavourzyme exhibited significant radical scavenging activity; For DPPH radical, the EC50values of MMPH and RPPH were 33.0 mg/mL and 93.0 mg/mL, respectively, and for hydroxyl radical, the EC50values of the protein hydrolysates were 7.5 mg/mL and 7.0 mg/mL, respectively; The protein hydrolysates were further fractionated by ultrafiltration membrane of 6000 Da, and the radical scavenging activity of the resultant fraction with lower molecular weight (<6000 Da) was significantly (P<0.05) increased, and for DPPH radical, the EC50values of MMPH and RPPH fractions were 29.5 mg/mL and 58.5 mg/mL, respectively, and for hydroxyl radical, the EC50 values of the fractions were 6.0 mg/mL and 7.0 mg/mL, respectively.