Cold plasma inactivates Salmonella stanley and Escherichia coli O157:H7 inoculated on Golden Delicious apples
Cold plasma inactivates Salmonella stanley and Escherichia coli O157:H7 inoculated on Golden Delicious apples
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DOI：
10.4315/0362-028x-71.7.1357
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发表时间：
2008-07-01
影响因子：
2
通讯作者：
Sites, Joseph
中科院分区：
文献类型：
--
作者：
Niemira, Brendan A.;Sites, Joseph
冷等离子体产生的滑动弧施加到爆发菌株的大肠杆菌O 157：117和沙门氏菌斯坦利琼脂平板上，并接种到金冠苹果的表面上。这种新的消毒技术灭活了琼脂平板上的两种病原体，观察到较高流速（40升/分钟）比较低流速（20升/分钟）更有效，与处理时间（1或2分钟）无关。金冠苹果用不同流速（10、20、30或40升/分钟）的冷等离子体处理不同时间（1、2或3分钟），应用于干燥的斑点接种。所有处理导致与未处理的对照相比显著（P < 0.05）减少，其中40升/分钟比较低流速更有效。灭活沙门氏菌斯坦利遵循一个时间依赖性的减少所有流量。3分钟后的减少范围为2.9至3.7 log CFU/ml，接近检测限。大肠coliO 157：H7，40升/分钟对于所有处理时间给出类似的减少，3.4至3.6log CFU/ml。在较低的流速下，灭活与暴露时间有关，3分钟导致2.6至3 log CFU/ml的减少。处理过的苹果的温度升高与所有流速的暴露时间有关。任何等离子体处理的苹果的最高温度为50.8摄氏度（高于环境温度28摄氏度），在20升/分钟持续3分钟后，表明抗菌效果不是热的结果。这些结果表明，冷等离子体是一个非热的过程，可以有效地减少人类病原体接种到新鲜农产品。
Cold plasma generated in a gliding arc was applied to outbreak strains of Escherichia coli O157:117 and Salmonella Stanley on agar plates and inoculated onto the surfaces of Golden Delicious apples. This novel sanitizing technology inactivated both pathogens on agar plates, with higher flow rate (40 liters/min) observed to be more efficacious than were lower flow rates (20 liters/min), irrespective of treatment time (1 or 2 min). Golden Delicious apples were treated with various flow rates (10, 20, 30, or 40 liters/min) of cold plasma for various times (1, 2, or 3 min), applied to dried spot inoculations. All treatments resulted in significant (P < 0.05) reductions from the untreated control, with 40 liters/min more effective than were lower flow rates. Inactivation of Salmonella Stanley followed a time-dependent reduction for all flow rates. Reductions after 3 min ranged from 2.9 to 3.7 log CFU/ml, close to the limit of detection. For E. coli O157:H7, 40 liters/min gave similar reductions for all treatment times, 3.4 to 3.6 log CFU/ml. At lower flow rates, inactivation was related to exposure time, with 3 min resulting in reductions of 2.6 to 3 log CFU/ml. Temperature increase of the treated apples was related to exposure time for all flow rates. The maximum temperature of any plasma-treated apple was 50.8 degrees C (28 degrees C above ambient), after 20 liters/min for 3 min, indicating that antimicrobial effects were not the result of heat. These results indicate that cold plasma is a nonthermal process that can effectively reduce human pathogens inoculated onto fresh produce.