二氧化氯对大肠杆菌作用机理的研究

STUDY ON MECHANISM OF EFFECT OF CHLORINE DIOXIDE ON Escherichia coli

目的以大肠杆菌为对象,研究二氧化氯杀菌机理。方法采用分子生物学技术和电镜观察方法进行了实验室观察。结果用含100 mg/L的二氧化氯消毒液作用10 m in,对大肠杆菌的杀灭率达到100%。以10 mg/L与100 mg/L二氧化氯作用后,很快即出现大肠杆菌蛋白质漏出现象,其漏出量随作用时间的延长而增加。100 mg/L的二氧化氯作用后,细菌体内ATP、钙离子、钾离子等均有明显漏出,但对核酸损伤不明显。透射电镜的观察发现,10 mg/L二氧化氯作用60 m in,大肠杆菌菌体仍保有较完好的外部形态,胞质仅有轻微的凝集现象;100 mg/L二氧化氯作用后,大肠杆菌细胞壁有显著皱褶,少数菌体胞壁出现破裂。结论核酸并不是二氧化氯杀菌时的靶位点,胞内物质的渗漏与细菌致死的联系并不十分明显,二氧化氯的杀菌机理可能在于对细胞质的凝集作用上。

Objective To study the germicidal mechanism of chlorine dioxide with Escherichia coli as the experimental object. Method Molecular biology technique and electronmicroscopic observation method were used to carry out laboratory observation. Results The disinfectant solution containing chlorine dioxide 100 mg/L with a 10 rain contact time killed 100% ofEscherichia coli. After exposure to 10 mg/L and 100 mg/L chlorine dioxide, E. coli showed leakage of protein immediately and the amount of leakage increased with prolonging the contact time. After exposure to 100 mg/L chlorine dioxide, ATP, Ca^＋＋ ion and K^＋ ion in the bacterial thalli leaked out obviously, but injury to nucleic acid was not significant. Transmission electronmicroscopic observation found that after exposure to 10 mg/L chlorine dioxide for 60 min, E. coli thalli still had intact external shape and only slight agglutination of cytoplasm. After exposure to 100 mg/L chlorine dioxide, the cell wall ofE. coli showed obvious folds and the cell wall of a few bacterial thalli showed rupture. Conclusion Nucleic acid is not the target of germicidal action of chlorine dioxide. The relation between leakage of intracellular substance and death of bacteria is not significant. The germicidal mechanism of chlorine dioxide may be the agglutination of cytoplasm.