关键词: 灰树花, 酶解, 多肽, 亚铁螯合能力, 抗氧化

Abstract: In this study, the optimal conditions for iron-chelating peptides from Grifola frondosa were explored, and their antioxidant capacities were evaluated. Six commercial enzymes were selected to hydrolyze Grifola frondosa protein, according to iron-chelating activity. One-factor-at-a-time and orthogonal array designs were employed to optimize the hydrolysis conditions based on iron-chelating activity. In the meantime, the antioxidant capacities were studied using DPPH and hydroxyl radical scavenging activities. The results showed that the peptides with highest iron-chelating activity were hydrolyzed on alkaline protease. The optimal enzymatic hydrolysis conditions were as follows: pH values, 9; alkaline protease dose, 1800 U/g; temperature, 55 ℃; substrate concentration, 0.5%(w/v); time, 2.5 h. Under these conditions, the iron-chelating activity and the degree of hydrolysis were 1.854 mg/g and 6.14%. The peptides showed scavenging activity against DPPH radicals and hydroxyl radicals which was relative to the concentrations. The Grifola frondosa peptides which have good ability of iron-chelating and antioxidant activities might be used in functional foods.

Key words: Grifola frondosa, hydrolisis, peptides, iron-chelating activity, antioxidant activity