Schilling, M. Wes
Silva, Juan L.
Date of Degree
Graduate Thesis - Open Access
Master of Science
College of Agriculture and Life Sciences
Department of Food Science, Nutrition and Health Promotion
The purpose of this study is to determine the effect of temperature on inducing an alkaline-tolerance response in L. monocytogenes (Lm) serotypes 1/2a and 4b. When Lm cells were pre-exposed to a sublethal alkali pH of 9.0 at different temperatures, two main patterns were observed: (1) Alkali-stress adaptation was readily induced in Lm when cells were pre-exposed to a sublethal alkali pH of 9.0 for 5-15 min at 37°C or 22°C; and (2) Alkali-stress adaptation was not induced in Lm when cells were pre-exposed to a sublethal alkali pH of 9.0 for 1 h at 4°C. However, exposure of Lm to 4°C for 24 h enhanced its survival against lethal alkaline challenge (pH 11.5). Also, alkali-stress adaptation if occurred at 37°C or 22°C was highly stable at 4ºC even in the absence of mild alkaline stress which should be taken into account while conducting risk analysis for this pathogen.
Pandare, Pooja, "Influence of Temperature on the Induction of Alkali-Stress Adaptation and its Stability in Listeria Monocytogenes Serotypes 1/2a and 4b" (2013). Theses and Dissertations MSU. 2720.