鼠伤寒沙门氏菌的紫外灭活及光复活抑制的研究

研究了鼠伤寒沙门氏菌的紫外失活动力学、在日光灯下的光复活现象以及氯对其光复活的抑制。结果表明,鼠伤寒沙门氏菌的紫外失活动力学曲线分为滞后区、一级动力学区、拖尾区三阶段,在PBS中的一级动力学失活速率常数为0.9041 cm2/mJ。而紫外灭活后的鼠伤寒沙门氏菌在日光灯下存在光复活。当紫外剂量为10 mJ/cm2时,鼠伤寒沙门氏菌在日光灯下照射3 h内发生明显的光复活,浓度从8.6×103CFU/mL增加到4.1×106 CFU/mL;但是在紫外消毒后,投加1 mg/L的氯可以有效抑制该细菌的光复活,投加2 mg/L的氯可以在10 min内全部灭活。因此,紫外-氯联合消毒能够有效的抑制鼠伤寒沙门氏菌细菌光复活,使其得到高效灭活。

Inactivation with ultraviolet and control of photoreactivation of Salmonella typhimurium

The objective of the study was to investigate the inactivation effect of Salmonella typhimurium(S.typhimurium) with ultraviolet(UV) disinfection individual and photoreactivation of S.typhimurium following low uv lamps under fluorescent lamps and to control repair of S.typhimurium with chlorine.Results show that UV inactivation kinetics of S.typhimurium consisted of three distinct phases including shoulder,linear first order and tailing and that inactivation rate coefficient of first order linear zone was 0.9041 cm2/mJ in PBS.Obvious evidence of repair was observed under light following low UV lamps irradiation.The concentration of S.typhimurium increased from 8.6×103CFU/mL to 4.1×106 CFU/mL with 3 h irradiation of fluorescent lamps following UV disinfection with UV dose of 10 mJ/cm2;little repair was observed with the combination of 1 mg/L of chlorine and absolute inactivation was achieved with 2 mg/L of chlorine within 10 min,under light following low UV lamps irradiation with UV dose of 10 mJ/cm2.Hence,combination of UV and chlorine controls photoreactivation of S.typhimurium and inactivates it effectively.