二氧化氯灭活水中隐孢子虫的影响因素及机理研究

Cryptosporidium inactivated by chlorine dioxide in water and disinfect mechanisms

以荧光活体染色法研究了ClO2浓度、灭活时间、浊度、pH值、温度、有机物含量等,对ClO2灭活隐孢子虫效果的影响,并利用扫描电镜和蛋白质实验初步探究了灭活机理.结果显示,当pH7.0,水温为25℃,浊度为1NTU时,投加3mg/L ClO2经过120min,可以达到最适消毒效果(存活率小于1%),隐孢子虫的灭活率与ClO2投加浓度、作用时间成非线性正相关.浊度是影响ClO2灭活隐孢子虫的主要因素,浊度越低,灭活效果越佳;水温(较)低,灭活效果稍差;酸性较于碱性更适宜ClO2灭活隐孢子虫;可溶性有机物一定程度上影响ClO2的灭活效果.扫描电镜和蛋白试验表明,ClO2主要破坏其细胞表面结构,从而引起隐孢子虫死亡.

The fluorescence staining method was used to study the effect of chlorine dioxide（ClO2） inactivating Cryptosporidium in water and affecting factors（ClO2 concentrations,inactivating times,pH values,temperatures,turbidities and organic contents）.Then the scanning electron microscopy（SEM） and protein assay were used to investigate cell ultrastructures variation to shed light on the mechanism of inactivation preliminarily.It could achieve the optimum disinfection effect（the survival rate of less than 1%） when adding 3.0mg/L of ClO2 after 120min（pH=7.0,25℃ and turbidity 1NTU）,the survival rate of Cryptosporidium cysts had a non-linear positive correlation with chlorine dioxide concentration and reaction time.The turbidity on inactivation effects was also found to be statistically significant in artificial water.With increases in turbidity,the inactivating effect decreased.Inactivating rate might rise with the temperature increasing.The inactivating capability was found to be stronger under acidic than that under alkalic conditions.In some extent,concentrations of organic matter could inhibit the disinfecting effect of ClO2.Examined by scanning electron microscopy（SEM） and protein assay showed that the cell surface was damaged,some cells started the cytoplasm leakage,and then caused Cryptosporidium death.