波纹巴非蛤蛋白酶解产物的抗氧活性及分子量分布研究

Antioxidant Activity and Molecular Weight Distribution of Hydrolysates from Paphia Undulate Protein

以波纹巴非蛤为原料,分离得到肌浆蛋白、肌原纤维蛋白、基质蛋白3种蛋白组分,分别研究其氨基酸组成及其胰蛋白酶酶解产物的体外抗氧化活性及分子量分布。结果表明该三种蛋白质中必需氨基酸、碱性氨基酸、疏水性氨基酸和支链氨基酸含量较高。抗氧化实验结果显示,三种蛋白对DPPH自由基、羟基自由基和超氧阴离子自由基均有一定的清除效果,且清除率与酶解液浓度存在一定的量效关系。与其它两种蛋白酶解产物相比,肌浆蛋白酶解液中小分子肽含量最高,分子量小于1500 u占42.55±0.27%,其对自由基清除效果也明显高于其它两种蛋白酶解液,对DPPH自由基、羟基自由基和超氧阴离子自由清除活性的IC50值分别为4.82、4.70和3.75 mg/mL。肌浆蛋白和肌原纤维蛋白酶解产物的还原能力相当,浓度为10 mg/mL时,其OD700分别为0.58和0.57,基质蛋白酶解产物的还原能力较弱。

Three types of protein including sareoplasmic protein, myofibrillar protein and stromal protein from Paphia undulate were isolated. The amino acid composition, antioxidant activity in vitro and molecular weight distribution of the hydrolysates prepared with trypsin were investigated. All of the three protein factions contained higher contents of essential amino acids, alkaline, hydrophobic and branched-chain amino acid. Protein hydrolysates showed a good radical scavenging activity with dose-effect. The hydrolysates of sarcoplasmic protein with the highest contents of small molecule peptide exhibited the strongest radical scavenging activities including DPPH radical, hydroxyl radical and superoxide anion radical, with the IC50 values being 4.82, 4.70 and 3.75 mg/mL, respectively and the molecular weight less than 1500 u accounted for 42.55±0.27%. The hydrolysates of sarcoplasmic protein and myofibrillar protein showed similar reducing power and their OD70owere 0.58 and 0.57 at 10 mg/mL, respectively. While the hydrolysates of stromal protein displayed lower reducing power.