鲢鱼酶解产物分子质量组成与抗氧化性

Molecular Weight and Antioxidant Activity of Enzymatic Hydrolysates of Silver Carp

以脱脂鲢鱼粉为原料,采用复合蛋白酶(Protamex)及碱性蛋白酶(Alcalase)控制酶解制备不同水解度(DH)的酶解产物,研究不同水解度酶解产物的分子质量组成,并以总抗氧化能力、羟自由基(·OH)清除能力、抗脂质氧化能力、超氧阴离子自由基(O2-·)清除能力为指标研究酶解产物的抗氧化活性。结果表明:碱性蛋白酶酶解鲢鱼粉后获得的酶解产物分子质量均低于复合蛋白酶的酶解产物,在水解度为10%的体系中,95%以上肽的分子质量集中在1500u以下;两种蛋白酶控制酶解制备的酶解产物均具有良好的抗氧化能力,其中碱性蛋白酶酶解产物DH为10%时的总抗氧化能力和抑制·OH能力效果最好,分别为1.025U/mg pro和21.31U/mg pro;复合蛋白酶酶解产物DH10%时的O2-·清除能力和抑制脂质氧化能力最好,O2-·清除能力为24.92U/mg pro,质量浓度5.0mg/mL时对脂质过氧化抑制率为27.88%;两种蛋白酶水解鲢鱼获得的酶解产物的分子质量组成与抗氧化性有一定关系,但相关性不显著。

The molecular weight （Mw） and antioxidant properties of enzymatic hydrolysates of silver carp with different degree of hydrolysis （DH） were studied. The antioxidant properties evaluated included total antioxidant capacity （T-AOC）, radical scavenging activity against hydroxyl and superoxide anion free radicals and lipid oxidation inhibitory effect. The hydrolysates were prepared by respective use of protamex and alcalase. The results showed that the Mw of the hydrolysates produced by alcalase were generally lower than those of the hydrolysates obtained with Protamex, and at DH 10%, over 95% of peptides fractions had Mw lower than 1500 u. The hydrolysates prepared by each enzyme preparation had excellent antioxidant activities. The hydrolysates with DH 10% prepared by alcalase possessed the highest T-AOC and hydroxyl radical scavenging capacity, which were 1.025 U/mg pro and 21.31 U/mg pro, respectively. The hydrolysates with DH 10% prepared by protamex displayed the strongest superoxide anion radical scavenging ability and lipid oxidation inhibitory effect, which reached 24.92 U/mg pro and 27.88% at a concentration of 5.0 mg/mL, respectively. The antioxidant activities of these hydrolysates might be related to their molecular weights despite being not significant.