本文选择胰酶对秋刀鱼蛋白进行酶解，以蛋白质利用率和氧化自由基吸收能力（ORAC值）为指标，运用响应面分析法优化秋刀鱼蛋白制备抗氧化肽的酶解工艺，并且对酶解产物的特性进行了研究。结果表明：最优酶解条件为加酶量1085 U/g蛋白，水料比3:1，酶解时间8 h时，此时蛋白质利用率和ORAC值分别为76.86%和883.40 μmol Trolox equivalent/g。秋刀鱼酶解产物的总氨基酸含量为4576.69 mg/100 mL，其中游离氨基酸和肽态氨基酸分别占34.28%和65.31%；总氨基酸中必需氨基酸占34.76%，抗氧化活性氨基酸和支链氨基酸占26.25%，说明秋刀鱼酶解产物具有较高的营养价值。秋刀鱼酶解产物中相对分子质量在1000~3000 Da之间的组分最多，占44.18%。秋刀鱼酶解产物清除DPPH?的IC50值为3.32 mg/mL，清除O2－?的IC50值为5.08 mg/mL，当秋刀鱼酶解产物的蛋白浓度为10 mg/mL时，其吸光值为0.67，说明秋刀鱼酶解产物具有较高的抗氧化活性。

In this study, trypsin was used for the enzymatic hydrolysis of proteins from Pacific saury. Based on the protein utilization ratio and oxidative free radical absorbance capacity (ORAC), the enzymatic hydrolysis technology was optimized for the preparation of antioxidant peptides from Pacific saury proteins by using a resonance surface analysis. The characteristics of the enzymatic hydrolysates were also examined. The optimal enzymatic hydrolysis conditions were as follows: enzyme dosage, 1,085 U/g; liquid-to-solid ratio, 3:1; and hydrolysis duration, 8 h. Under these conditions, the protein utilization ratio was 76.86%, and ORAC value was 883.40 μmol Trolox equivalent/g. The total amino acid content was 4,576.69 mg/100 mL in the enzymatic hydrolysates from Pacific saury, of which 34.28% were free amino acids and 65.31% were peptides. Among the total amino acids, essential amino acids accounted for 34.76% and antioxidant amino acids and branched-chain amino acids accounted for 26.25%. These results indicated that Pacific saury has high nutritional value. Hydrolysates with molecular weights of 1000~3000 Da were the most abundant and accounted for 44.18% of the enzymatic hydrolysates of Pacific saury. Moreover, the enzymatic hydrolysates showed DPPH radical scavenging activity (IC50 value, 3.32 mg/mL), O2- radical scavenging activity (IC50 value, 5.08 mg/mL), and light absorption power (0.67 at 10.0 mg/mL). Thus, enzymatic hydrolysates of Pacific saury have relatively high antioxidant activities.

十二五”国家科技支撑计划项目（2012BAD33B03，2012BAD37B08）