贻贝蛋白的酶解及其酶解物的抗氧化活性研究

比较了6种不同的蛋白酶(胰蛋白酶、风味蛋白酶、中性蛋白酶、木瓜蛋白酶、复合蛋白酶、碱性蛋白酶)对贻贝粗蛋白的酶解效果,确定碱性蛋白酶为最适用酶。用此酶制备不同水解度(DH 6%、DH 11.5%、DH16%、DH 20%、DH 25%)的贻贝蛋白酶解物,考察不同DH酶解产物的抗氧化活性。试验结果表明:贻贝酶解产物具有较强的抗氧化活性,并呈一定的量效关系;当DH为25%时,贻贝酶解物对DPPH自由基、超氧自由基、羟基自由基的清除率最高,分别为77.4%、75.2%、43.4%,同时具有最强的金属螯合率(64.7%);而DH为16%时,酶解物对亚油酸的过氧化抑制作用较还原型谷胱甘肽强,达65.6%。DH对酶解产物的抗氧化活性有一定的影响,但在不同的抗氧化体系中,影响趋势不一致。

Enzymatic Hydrolysis of Mussel (Mytilus edulis) Protein and Antioxidant Activity of Hydrolysates

Mytilus edulis protein was hydrolyzed using six different proteases(Trypsin,Flavourzyme,Neutrase,Papain,Protamex,Alcalase).The results showed Alcalase was the optimal hydrolytic enzyme for its best hydrolyzing capacity and higher protein recovery.Mussel protein hydrolysate(MPH) with different degree of hydrolysis(DH) was prepared by Alcalase under its recommended conditions,and the antioxidant activity of MPH was also evaluated by employing several in vitro assay systems.The results showed that MPH exhibited notable antioxidative activity with a dose-dependent manner.When DH was 25%,MPH showed the strongest DPPH/superoxide/hydroxyl radical-scavenging activity and ferrous ion-chelating activity.The scavenging/chelating rates were found to be 77.4%,75.2%,43.4% and 64.7%,respectively.The strongest lipid peroxidation inhibitory rate was found to be 65.6% when DH was 16%,which was higher than that of glutathione(GSH).Also,MPH exhibited notable reducing power.