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目的:评估脉冲光辐照强度对微生物的杀灭效果，为杀菌技术设计提供验证依据。方法:以金黄色葡萄球菌(ATCC25923)、枯草芽孢杆菌(ATCC9372)为实验菌，用载体定量杀菌方法评估杀菌效果，指数稀释、倾注培养计数法计算杀菌效率。用扫描电镜和透射电镜观察光照强度对细菌结构的影响。实验设置细菌对照组：未经脉冲光照射处理的相同初始浓度菌，平行培养30、60和90 s。细菌实验组：分别距离脉冲光源50、100、150和200 cm 4个点接受辐照处理，同样设置30、60和90 s 3个辐照时间点。结果:距离脉冲光源50、100 cm时，照射30 s金黄色葡萄球菌灭活率为100%。枯草芽孢杆菌灭活率为99.9%。当细菌距离光源为150 cm时，金黄色葡萄球菌辐照30、60和90 s的灭活率分别为81.9%、95.4%、100%，枯草芽孢杆菌的灭活率分别为76.0%、92.3%和99.9%。当辐照距离提高至200 cm时，脉冲光对细菌的灭活效率明显下降，3个检测时间点金黄色葡萄球菌灭活效率分别为24.5%、38.8%、48.8%，枯草芽孢杆菌分别为14.2%、20.0%、28.5%。结论:脉冲光能迅速灭活微生物，灭活速度、效率与光照强度密切相关。“,”Objective:To study the inactivation efficacy of pulsed light with different irradiation intensities on microorganisms, so as to provide a validation for the design of sterilization techniques.Methods:Using Staphylococcus aureus (ATCC25923) and Bacillus subtilis (ATCC9372) as experimental bacteria. The carrier quantitative germicidal test was used to evaluate the inactivation efficacy. The exponential dilution method and the pour plate method were used to measure the inactivation efficacy. The scanning electron microscope and transmission electron microscope were used to observe the effects of different irradiation intensities of light on bacterial structure. The bacterial control group (CO group) and the bacterial test group (T group) were set up with the same initial concentration in the experiment. In the CO group, the bacteria without pulsed light irradiation were cultured in parallel for 30 s, 60 s, and 90 s. In the T group, bacteria received irradiation 50 cm, 100 cm, 150 cm, and 200 cm away from the pulsed light source respectively, and the irradiation time duration was set as 30 s, 60 s, and 90 s for each distance.Results:The inactivation rate of ATCC25923 was 100% and that of ATCC9372 was 99.9% when they were 50 cm and 100 cm away from the pulsed light source for 30 s. When the irradiation distance was increased to 150 cm, the inactivation rates of ATCC25923 for 30 s, 60 s, and 90 s were 81.9%, 95.4%, and 100%, respectively; and those of ATCC9372 were 76.0%, 92.3%, and 99.9%, respectively. When the irradiation distance was increased to 200 cm, the inactivation efficiency of pulsed light was significantly reduced; the inactivation rates of ATCC25923 at the three detection time points were reduced to 24.5%, 38.8%, and 48.8%, respectively, and those of ATCC9372 were reduced to 14.2%, 20.0%, and 28.5%.Conclusion:Pulsed light can quickly eradicate microorganisms, and its inactivation rate and efficiency are closely related to the intensity of irradiation.