文蛤活性蛋白的分离及体外抗氧化作用

Isolation and antioxidation of bioactive proteins from Meretrix meretrix

目的研究文蛤肉活性蛋白体外抗氧化作用。方法采用匀浆、硫酸铵分级沉淀、Sephadex G-150柱层析从文蛤肉中分离到3个蛋白峰P1,P2和P3,测定其超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性和抑制脂质过氧化(LPO)作用。结果P2的CAT活性最高,比活力为77.0 U.mg-1;P3的SOD活性最高,比活力为68.8 U.mg-1;P3抑制LPO作用最强,20μg蛋白的抑制率为50%。经SDS-PAGE结果P1以相对分子质量18.0 kD的组分为主;P2存在与对照CAT相对应的条带,其相对分子质量约为28.0 kD;P3存在与对照SOD相对应的条带,其相对分子质量约为16.0 kD。结论从文蛤肉中分离到的活性蛋白具有抗氧化作用。

Objective To investigate the antioxidation of bioactive proteins from the meat of Meretrix rneretrix. Methods Three protein peaks（P1 ,P2 and P3） were isolated from the meat of Meretrix rneretrix by homogenating, step precipitating with ammonium sulfate, chromatography with Sephadex G-150. CAT activity and SOD activity of these proteins were determined; Inhibition of the proteins to lipid peroxidation was determined; Results CAT activity of P2 was the highest,its specific activity was 77.0 U · mg^-1. SOD activity of P; was the highest,its specific activity was 68.8 U · mg^-1. Inhibition of P3 to lipid peroxidation was the most obvious,its inhibitive rate was 50% when the protein content was 20 μg. SDS-PAGE results showed that the main composition of Pl was the protein,the Mr of which was 18.0 kD ; The protein band of P2 corresponded with the protein band of contrast CAT,its Mr was 28.0 kD. The protein band of P3 corresponded with the protein band of contrast SOD,its relative Mr was 16.0 kD. Conclusion The bioactive proteins were isolated from the meat of Meretrix meretrix, and the bioactive proteins had antioxidation.