不同处理方式下高压电场对大肠杆菌杀菌效应的比较研究

Sterilization Effects of High Voltage Electric Field on E. coli under Different Treatment Conditions

对大肠杆菌进行高压匀强电场杀菌效应的研究。通过干燥处理和溶液处理的比较实验发现:干燥处理对大肠杆菌灭活效果显著,随着时间的延长、电压的升高,其致死率呈上升趋势;当处理1min时:电压为1kV/cm存活率是对照的6倍以上,电压为2kV/cm,存活率是对照的约一半左右,之后随电压的升高,存活率与对照相比在20%上下波动;当处理10min时:电压为1kV/cm存活率是对照的49%,电压达3kV/cm及以上时,存活率为3%及以下。溶液处理下对大肠杆菌的灭活效果较差,存活率总的变化趋势呈振荡型。一定强度的场强可以促进大肠杆菌的萌发,使存活率提高。结果表明,相对溶液处理,干燥处理的杀菌效果显著,可望开发应用于干燥物料的消毒杀菌。

In the present study, sterilization effects of high voltage electric field （HVEF） on E. coli in aqueous solution and under dry condition were studied, respectively. The results indicated that the sterilization effects under dry condition are more conspicuous than those in aqueous solution. Under dry condition the sterilization rate ofE. coli is remarkably ascended with the increment of time and HVEF intensity. When treated for 1 min, the survival rate of E. coli under voltage at 1 kV/cm is 6 times of the control, that under voltage at 2 kV/cm is about half of the control, and then following with the increase of voltage, the survival rate is fluctuated around 20% of the control. When treated for 10 min, the survival rate of E. coli under voltage at 1 kV/cm is 49% of the control, and that under voltage over 3 kV/cm is less than 3% of the control. In aqueous solution, the variety tendency of survival rate of E. coli presents oscillatory type, and the effects are not satisfying. Altogether, the sterilization effects of HVEF under dry condition are significant, and may be applied in the disinfection and sterilization of dry materials.