Antioxidative Activities of Protein Hydrolyzates

Studies on Antioxidative Activities of Amino Compounds on Fats and Oils (Part IV)

Abstract

Hydrolyzating ratio of soybean protein by 10 kinds of protease preparation ranged from 5 to 34%. On the comparison of antioxidative activities among these hydrolyzates, the most effective antioxidative activity was recoganized in 6 to 9% of hydrolyzing ratio. In the case of eggwhite albumin hydrolyzates by 11 kinds of protease preparation, although hydrolyzing ratio did not influence on antioxidative activity of the hydrolyzate, synergistic effect of the hydrolyzate with d-δ-tocopherol was observed. Soybean protein hydrolyzates by 8 kinds of protease preparation were fractionated by gel-filtration with Sephadex G-25. In the comparison of antioxidative activity of each fraction, antioxidative activity patterns of hydrolyzates were classified into three types and the strongest antioxidative activity was found in the near fractions where the vitamin B₁₂ employed as a marker was eluted. In the same manner, hydrolyzates of milk casein, egg-white albumin and gelatin by protease were fractionated by gel-filtration with Sephadex G-25. The most effective antioxidative activity in all hydrolyzates was recognized in the peptides with a little higher molecular weight than that of vitamin B₁₂.