过氧化氢汽体对细菌芽孢与细菌繁殖体杀灭效果的比较

COMPARISON OF KILLING EFFECT OF VAPOR PHASE HYDROGEN PEROXIDE ON SPORES AND VEGETATIVE BACTERIA

目的比较细菌芽孢与细菌繁殖体对过氧化氢汽体（VPHP）的抗力,为选择VPHP生物指示剂提供参考。方法采用载体定量杀菌实验方法,比较某过氧化氢汽体发生器发生的VPHP对两组常用消毒试验指标菌芽孢与金黄色葡萄球菌杀灭效果,以评价此两种细菌芽孢作为VPHP生物指示剂的可能性。结果该VPHP发生器在20 m^3空间内运行0.5-1.0 h,室内中心点过氧化氢浓度均值为1 972-2 615 mg/m^3;运行1.5-2.5 h,室内中心点过氧化氢浓度均值为2 474-1 070 mg/m^3。启动该VPHP发生器运行2.5 h（一周期）,对不锈钢载体上的金黄色葡萄球菌、枯草杆菌黑色变种芽孢、嗜热脂肪杆菌芽孢杀灭对数值分别为2.32、4.18、〉5.00。结论该VPHP发生器在其设定的运行周期内,对金黄色葡萄球菌的杀灭效果明显低于两种细菌芽孢,提示仅以此两种细菌芽孢作为VPHP生物指示剂存在局限性。

Objective To compare the resistance of spores and vegetative bacteria against vapor phase hydrogen peroxide（ VPHP） for the selection of its biological indicator. Methods The carrier quantitative germicidal test was applied for comparison of killing effect of VPHP generated by a VPHP generator on two kinds of spores commonly used as test indicators and Staphylococcus aureus for exploration on the possibility of the two spores as biological indicators. Results The average concentration of VPHP was 1 972 - 2 615 mg /m^3 at the center of a 20 m^3 room after the generator＇s running for 0. 5 -1. 0 h,and 2474 - 1070 mg /m^3 after running for 1. 5 - 2. 5 h. The killing logarithm values of S. aureus,spores of Bacillus subtilis var. niger. and spores of Bacillus stearothermophilus contaminated on stainless steel carriers were 2. 32,4. 18 and 〉5. 00 after its running for 2. 5 h（ one running cycle）. Conclusion During the preset running cycle of the VPHP generator,its killing effect on S. aureus is considerably lower than those on the two spores,which suggests the limitation of the two spores as VPHP biological indicators.