鲶鱼体表黏液IgM的分离纯化及其抑菌活性研究

Extraction and Purification of IgM from Catfish Body Surface Mucus and Characterization of Its Antibacterial Activity

依次采用硫酸铵分级沉淀、离子交换层析和凝胶过滤层析法从鲶鱼体表黏液中分离纯化IgM,并对其抑菌活性进行了检测。通过试验可以得出,凝胶层析的最佳分离条件为:0.02 mol/L pH 8.0的Tris-HCl缓冲液、洗脱速度为0.3 mL/min。鲶鱼体表黏液中提取的IgM对大肠杆菌抑菌作用最强,其次是枯草芽孢杆菌,对藤黄微球菌抑菌效果最不明显。在低温贮存时温度控制在0～4℃,有助于保持其抑菌活性,但随着时间的延长,抑菌活性也会逐渐减弱。

Using ammonium sulfate gradient fractionation precipitation,ion-exchange column chromatography and gel filtration chromatography,IgM was purified from catfish body surface mucus,and the antibacterial activity was determined.The result showed that the best condition of gel filtration chromatography was eluting with 0.02 mol/L Tris-HCl buffer(pH 8.0),and the optimal eluant velocity was 0.3 mL/min.IgM extracted from catfish body surface mucus had the strongest antibacterial activity to Escherichia coli,and followed by Bacillus subtilis.The weakest antibacterial activity was found to Micrococcus luteus.Low temperature at 0-4 ℃ helped to keep antibacterial activity,while the antibacterial activity decreased with time increasing.