几种淡水鱼肌肉乙酰胆碱酯酶的盐析提取及农药敏感性研究

Extraction and Insecticides Susceptibility of Acetylcholinesterase from Muscle Tissues of Fresh Water Fishes

以鲢鱼、镛鱼和罗非鱼肌肉组织为材料,研究乙酰胆碱酯酶AChE的盐析提取方法及农药敏感性。结果表明,3种淡水鱼肌肉组织在55%硫酸铵饱和度时得到的沉淀酶总活力最高,乙酰胆碱酯酶的比活力分别达到0.264,0.263,0.221 U/mg,纯化倍数分别为1.222,1.277,1.190,回收率分别为27.626%,37.621%,26.441%。5种有机磷农药(敌敌畏,辛硫磷,马拉硫磷,乙酰甲胺磷,氧化乐果)对3种淡水鱼肌肉乙酰胆碱酯酶有抑制作用,其中罗非鱼AChE对敌敌畏最敏感,抑制中浓度I50为0.14μg/mL,对马拉硫磷最不敏感,抑制中浓度I50为11.

Acetylcholinesterase（AChE） from muscle tissues of Hypophthalmichthys molitrix,Aristichthys nobilis and Oreochromis aurea were extracted by（NH4）2SO4 fractional precipitation,and inhibition of insecticides were also studied.The specific activity of the extracted enzyme at 55%（NH4）2SO4 saturation were respectively 0.264,0.263,0.221 U·mg-1,purification fold 1.222,1.277,1.190,and recovery 22.626%,37.621%,26.441%.The enzyme activity was inhibited by 5 insecticides（dichlorvos,phoxim,malathion,acephate and folimat）.Dichlorvos from Oreochromis aurea exhibited strong inhibitions on this enzyme with I50 value of 0.14 μg.mL-1,and malathion has the weakest inhibition with I50 value of 11.202 μg.mL-1