Shanghai Institute of Pollution Control and Ecological Security, State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, People's Republic of China.
Shanghai Institute of Pollution Control and Ecological Security, State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, People's Republic of China.
Sci Total Environ. 2019 Jan 15;648:271-284. doi: 10.1016/j.scitotenv.2018.07.451. Epub 2018 Aug 4.
Chlorination is one of the most widely used disinfection techniques, and the problem of "chlorine-resistant bacteria" (CRB) has attracted more attention recently. In this study, the deactivation of typical CRB in water, Mycobacterium fortuitum (M. fortuitum) and Mycobacterium mucogenicum (M. mucogenicum), by free chlorine was investigated with Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis) as the reference. The chlorination effectiveness of chlorine on M. fortuitum and M. mucogenicum and the effect of chlorine concentration, pH, and humic acid were studied. It was found that M. mucogenicum was more resistant to chlorine than M. fortuitum, both of which were much more resistant than E. coli and B. subtilis. The effect of disinfectant concentration on the inactivation efficiency was positive, whereas the influence of pH and humic acid was negative. The inactivation mechanisms were explored by analyzing the bacteria morphology, the destruction of cell membrane, the cell hydrophobicity, as well as total adenosine triphosphate (ATP), superoxide dismutase (SOD) activity. The slight destruction of the cell membrane was observed after deactivation with chlorine, and high hydrophobicity of the cell membrane combined with metabolic changes might lead to the chlorine tolerance of Mycobacteria.
氯化消毒是一种应用最广泛的消毒技术，最近“抗氯菌”（CRB）的问题引起了更多的关注。本研究以大肠杆菌（E. coli）和枯草芽孢杆菌（B. subtilis）为参照，考察了游离氯对水中典型 CRB 分枝杆菌（M. fortuitum 和 M. mucogenicum）的灭活效果，并研究了氯浓度、pH 值和腐殖酸对其的影响。结果表明，M. mucogenicum 比 M. fortuitum 更能抵抗氯，而它们比 E. coli 和 B. subtilis 更能抵抗氯。消毒剂浓度对灭活效率的影响呈正相关，而 pH 值和腐殖酸的影响则呈负相关。通过分析细菌形态、细胞膜破坏、细胞疏水性以及三磷酸腺苷（ATP）总量、超氧化物歧化酶（SOD）活性，探讨了灭活机制。氯灭活后，观察到细胞膜有轻微破坏，细胞膜的高疏水性加上代谢变化可能导致分枝杆菌的抗氯性。
