Smoot L M, Pierson M D
Department of Food Science and Technology, Virginia Tech, Blacksburg 24061, USA.
J Food Prot. 1998 Oct;61(10):1293-8. doi: 10.4315/0362-028x-61.10.1293.
Attachment of Listeria monocytogenes Scott A to Buna-N rubber and stainless steel under different temperature and pH conditions at the time of cell growth or at the time of attachment was investigated. All experiments were conducted using sterile phosphate buffer to avoid cell growth during exposure to the test surfaces. Numbers of attached cells increased with increasing attachment temperature (10 to 45 degrees C) and exposure time for both test surfaces. Maximum levels of attached cells were obtained when cell growth occurred at 30 degrees C. Downward, but not upward, shifts in the cell suspension holding temperature prior to attachment to Buna-N rubber resulted in reduced adhered cell populations. Maximum levels of adhered cells to Buna-N rubber were not affected by adjustments of the attachment medium pH between 4 and 9. However, after short contact times (i.e., less than 30 min), levels of attached cells were lower when attachment occurred under alkaline conditions. Growth pH was also found to affect the levels of adhered cell populations to Buna-N rubber. L. monocytogenes Scott A attached to stainless steel at higher levels for all temperature and pH parameters evaluated in this study.
研究了在细胞生长时或附着时，不同温度和pH条件下单增李斯特菌斯科特A对丁腈橡胶和不锈钢的附着情况。所有实验均使用无菌磷酸盐缓冲液进行，以避免在暴露于测试表面期间细胞生长。对于两个测试表面，附着细胞的数量均随附着温度（10至45摄氏度）和暴露时间的增加而增加。当细胞在30摄氏度生长时，获得了附着细胞的最大水平。在附着于丁腈橡胶之前，细胞悬浮液保持温度向下（而非向上）变化会导致附着细胞数量减少。附着介质pH在4至9之间的调整对丁腈橡胶上附着细胞的最大水平没有影响。然而，在短接触时间（即少于30分钟）后，在碱性条件下附着时，附着细胞的水平较低。还发现生长pH会影响丁腈橡胶上附着细胞群体的水平。在本研究评估的所有温度和pH参数下，单增李斯特菌斯科特A附着于不锈钢的水平更高。
