沙丁鱼鱼鳞胶原蛋白肽的制备及其抗氧化活性研究

Study on the preparation of collagen peptides from Sardina pilchardus scales and its antioxidant activity

目的优化沙丁鱼(Sardinapilchardus)鱼鳞胶原蛋白肽的制备工艺和评价不同分子量大小胶原蛋白肽的抗氧化活性。方法以沙丁鱼鱼鳞为原料,通过酶工程结合单因素与响应面实验优化胶原蛋白肽制备工艺,采用超滤膜分级分离鱼鳞胶原蛋白肽,并通过体外自由基化学体系分析对比不同分子量大小(10、5、1 kDa)的胶原蛋白肽的抗氧化活性。结果采用碱性蛋白酶进行酶解鱼鳞,胶原蛋白肽的得率最高;最优酶解工艺参数为:碱性蛋白酶加酶量7526 U/g、料液比1:20(g/mL)、pH 10.5、酶解温度67℃、酶解时间4 h,此条件下鱼鳞胶原蛋白肽得率最高,达43.44%±1.59%。通过超滤获得的分子量小于1k Da的鱼鳞胶原蛋白肽对1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基和羟基自由基(hydroxyl radical,·OH)的清除能力最强,其半抑制浓度(half maximal inhibitory concentration,IC_(50))分别为0.72 mg/mL和1.76 mg/mL;分子量为1~5 kDa的鱼鳞胶原蛋白肽对超氧阴离子自由基(superoxide radical,O^(2-)·)的清除效果最好,其IC50为1.45 mg/mL。结论碱性蛋白酶能够有效制备鱼鳞胶原蛋白肽,且小于1 kDa的鱼鳞胶原蛋白肽抗氧化活性最好。

Objective To optimize the preparation of collagen peptides from the scales of Sardina pilchardus and evaluate the antioxidant activities of collagen peptides with different molecular weights.Methods Collagen peptides were extracted from the scales of Sardina pilchardus using enzyme engineering combined with single factor and response surface test,and then separated by ultrafiltration membrane.And the collagen peptides with different molecular weights(10,5,1 kDa)were obtained to analyze the antioxidant activities by free radical chemical system analysis in vitro.Results The yield rate of collagen peptides was highest when hydrolyzed by alkaline protease.The optimal enzymatic hydrolysis conditions were determined as follows:The dosage of alkaline protease was 7526 U/g,solid-liquid ratio of 1:20(g/mL),pH 10.5,hydrolysis temperature of 67℃,and hydrolysis time of 4 h.Under these conditions,the yield of collagen peptides from fish scales reached a maximum of 43.44%±1.59%.The scavenging capacity of collagen peptides with a molecular weight of less than 1 kDa against 1,1-diphenyl-2-trinitrophenyl hydrazine radical 1,1-diphenyl-2-picrylhydrazyl(DPPH)radical and hydroxyl radicals hydroxyl radical(·OH)were strongest,with the half maximal inhibitory concentration(IC_(50))of 0.72 and 1.76 mg/mL,respectively;the scavenging capacity of collagen peptides with a molecular weight of 1-5 kDa against superoxide anion radicals superoxide radical(O^(2-)·)was highest,with the IC 50 of 1.45 mg/mL.Conclusion Alkaline protease can effectively prepare fish scale collagen peptides,and fish scale collagen peptides with less than 1 kDa have the best antioxidant activity.