平皿材质对菌落总数检测结果影响的探讨

Influence of disposable plastic plate and glass plate on monitoring result of total number of bacterial colony

目的探讨在沉降法测定空气中菌落总数时,用一次性塑料平皿和玻璃平皿对监测结果的影响。方法在医院Ⅲ类区及公共场所各设25个采样点,同一采样点、同一时间、同时放置两种平皿采用自然沉降法采集空气中的菌落总数进行监测结果比较;并用倾注法验证日常菌种接种中使用玻璃平皿与一次性塑料平皿的差异性。结果在医院Ⅲ类区及公共场所各设的25个采样点中,医院Ⅲ类区用玻璃平皿收集培养的结果平均为33,用一次性塑料平皿收集培养的结果平均为27;公共场所用玻璃平皿收集培养的结果平均为14,用一次性塑料平皿收集培养的结果平均为11。结论使用不同材质的平皿对沉降法测定空气中菌落总数结果有显著的影响,用玻璃平皿收集培养的空气中的菌落总数多于用一次性塑料平皿收集培养的空气中的菌落总数,沉降法测定空气菌落总数监测中建议应用玻璃平皿。

Objective To discuss the influence of disposable plastic plate and glass plate on the monitoring resuh when we measured the total number of bacterial colony in the air by sedimentation. Methods Totally 25 sampling points were set up in the third area of hospital and public places. Two kinds of plates are placed at the same time and in the same sampling points, to collect the total number of bacterial colony in the air by natural sedimentation, compare the monito- ring result and verify the discrepancy between disposable plastic plates and glass plates, which were used in the daily strain inoculation with plate pouring method. Results In the 25 sampling points which were set up in the third area of hospital and public places, the average result of glass plate in the third area of hospital was 33, and the average result of disposable plastic plate in the same place was 27. The average result of glass plate in public places was 14, and the av- erage result of disposable plastic plate in the same place was 11. Conclusion Different materials of plate have a signifi- cant impact on the monitoring result of measuring the total number of bacterial colony in the air by sedimentation. Glass plates could collect more bacterial colony in the air than disposable plastic plates. Therefore, glass plates are recommen- ded when measuring the total number of bacterial colony in the air by sedimentation.