【摘要】 针对二级出水中的一株环丙沙星耐药菌,研究了菌株生长特性和光辐照对其灭活、复活及耐药性的影响.结果表明,该菌株对青霉素、氨苄西林、磺胺甲恶唑、四环素和利福平均具有耐受性,在环丙沙星存在的条件下,其最大比生长速率由0.63h^-1降低到0.51h^-1.光辐照对环丙沙星耐药菌的灭活率基本随光照强度和辐照时间的增加而升高,且基本符合零级或一级化学反应动力学.可见光（100/300/500W汞灯和1000W氙灯（>400nm））辐照60min,环丙沙星耐药菌灭活率达到0.25⁰.39log.100/300W汞灯和1000W氙灯（>400nm）辐照下环丙沙星耐药菌的变化符合零级反应动力学,灭活速率为10196.43¹1345.24CFU/（m L·min）,500W汞灯（>400nm）辐照下环丙沙星耐药菌的变化符合一级反应动力学,灭活速率为0.01min^-1.可见光+UVA（100/300/500W汞灯和1000W氙灯（>300nm））辐照60min,环丙沙星耐药菌灭活率达到0.30⁵.63log.100W汞灯（>300nm）辐照下环丙沙星耐药菌的变化符合一级反应动力学,灭活速率为0.01min^-1,300W汞灯（>300nm）辐照下环丙沙星耐药菌的变化符合零级反应动力学,灭活速率为2572.02CFU/（m L·min）.未完全灭活的耐药菌存在复活,其48h光、暗复活率达到-3.9%¹23.4%.在光辐照过程中,只有1000W可见光+UVA辐照影响环丙沙星耐药菌的耐药性,辐照60min,其抑菌圈直径由11.0mm下降到8.0mm.更多还原

【Abstract】 A ciprofloxacin-resistant bacterium strain was isolated from secondary treated effluent, and effects of light irradiation for disinfection of ciprofloxacin-resistant bacterium strain were investigated. The ciprofloxacin-resistant bacterium strain presented resistance to penicillin, ampilicillin, sulfamethoxazole, tetracyline and rifampicin. In the presence of ciprofloxacin, the maximum specific growth rate of the strain decreased from 0.63h^-1 to 0.51h^-1. The inactivation ratio of ciprofloxacin-resistant bacterium strain raised with increasing of light intensity and irradiation time, and the inactivated reaction followed either the zero order or first order kinetics. By irradiation of visible light（100/300/500 W mercury lamp and 1000 W xenon lamp（>400nm）） for 60 min, the inactivation ratio of ciprofloxacin-resistant bacterium strain reached 0.25⁰.39 log. The inactivated reaction by 100/300 W mercury lamp and 1000 W xenon lamp（>400nm） irradiation fited in with zero order kinetics, and the reaction rate constant was 10196.43¹1345.24CFU/（m L·min）. The inactivated reaction by 500 W mercury lamp（>400nm） followed first order kinetics, and the reaction rate constant was 0.01min^-1. By irradiation of visible light with UVA（100/300/500 W mercury lamp and 1000 W xenon lamp（>300nm）） for 60 min, the inactivation ratio of ciprofloxacin-resistant bacteria reached 0.30⁵.63 log. The inactivated reaction by 100 W mercury lamp（>300nm） followed first order kinetics, and the reaction rate constant was 0.01min^-1. The inactivated reaction by 300 W mercury lamp（>300nm） irradiation fited in with zero order kinetics, and the reaction rate constant was 2572.02CFU/（m L·min）. Both of photo reactivation and dark repair took place when ciprofloxacin-resistant bacteria were not completely inactivated. The reactivation ratio reached-3.9¹23.4% after photo reactivation of 48 h and dark repair. During light irradiation, the ciprofloxacin resistance of the strain was only affected by 1000 W visible light with UVA irradiation. By irradiation for 60 min, its inhibition diameter decreased from 11.0mm to 8.0mm.更多还原