Kelly-Wintenberg K, Montie T C, Brickman C, Roth J R, Carr A K, Sorge K, Wadsworth L C, Tsai P P
Department of Microbiology, University of Tennessee, Knoxville 37996, USA.
J Ind Microbiol Biotechnol. 1998 Jan;20(1):69-74. doi: 10.1038/sj.jim.2900482.
We report the results of an interdisciplinary collaboration formed to assess the sterilizing capabilities of the One Atmosphere Uniform Glow Discharge Plasma (OAUGDP). This newly-invented source of glow discharge plasma (the fourth state of matter) is capable of operating at atmospheric pressure in air and other gases, and of providing antimicrobial active species to surfaces and workpieces at room temperature as judged by viable plate counts. OAUGDP exposures have reduced log numbers of bacteria, Staphylococcus aureus and Escherichia coli, and endospores from Bacillus stearothermophilus and Bacillus subtilis on seeded solid surfaces, fabrics, filter paper, and powdered culture media at room temperature. Initial experimental data showed a two-log10 CFU reduction of bacteria when 2 x 10(2) cells were seeded on filter paper. Results showed > or = 3 log10 CFU reduction when polypropylene samples seeded with E. coli (5 x 10(4)) were exposed, while a 30 s exposure time was required for similar killing with S. aureus-seeded polypropylene samples. The exposure times required to effect > or = 6 log10 CFU reduction of E. coli and S. aureus on polypropylene samples were no longer than 30 s. Experiments with seeded samples in sealed commercial sterilization bags showed little or no differences in exposure times compared to unwrapped samples. Plasma exposure times of less than 5 min generated > or = 5 log10 CFU reduction of commercially prepared Bacillus subtilis spores (1 x 10(5)); 7 min OAUGDP exposures were required to generate a > or = 3 log10 CFU reduction for Bacillus stearothermophilus spores. For all microorganisms tested, a biphasic curve was generated when the number of survivors vs time was plotted in dose-response cures. Several proposed mechanisms of killing at room temperature by the OAUGDP are discussed.
我们报告了一项跨学科合作的结果，该合作旨在评估单一大气层均匀辉光放电等离子体（OAUGDP）的杀菌能力。这种新发明的辉光放电等离子体源（物质的第四态）能够在大气压力下于空气和其他气体中运行，并通过活菌平板计数判断，能够在室温下为表面和工件提供抗菌活性物质。在室温下，OAUGDP处理已减少了接种在固体表面、织物、滤纸和粉状培养基上的金黄色葡萄球菌、大肠杆菌以及嗜热脂肪芽孢杆菌和枯草芽孢杆菌的芽孢的对数数量。初步实验数据表明，当在滤纸上接种2×10²个细胞时，细菌数量减少了两个对数10 CFU。结果显示，接种大肠杆菌（5×10⁴）的聚丙烯样品暴露后，CFU减少量≥3个对数10，而接种金黄色葡萄球菌的聚丙烯样品达到类似杀灭效果则需要30秒的暴露时间。在聚丙烯样品上实现大肠杆菌和金黄色葡萄球菌CFU减少量≥6个对数10所需的暴露时间不超过30秒。在密封的商业灭菌袋中对接种样品进行的实验表明，与未包装的样品相比，暴露时间几乎没有差异。等离子体暴露时间少于5分钟可使商业制备的枯草芽孢杆菌芽孢（1×10⁵）的CFU减少量≥5个对数10；嗜热脂肪芽孢杆菌芽孢的CFU减少量≥3个对数10则需要7分钟的OAUGDP暴露时间。对于所有测试的微生物，在剂量反应曲线中绘制存活菌数与时间的关系时，均产生了双相曲线。本文讨论了OAUGDP在室温下杀菌的几种可能机制。
