The purpose of this study was to induce an oxidative-stress adaptation in Listeria monocytogenes Bug600 (serotype 1/2a) and F1057 (serotype 4b) by pre-exposing to sublethal H2O2 and alkali-stress either singly or sequentially. Our findings show that the sequential pre-exposure of cells to pH 9 for 30 min treatment followed by 50 ppm H2O2 for 30 min at 37°C yielded the highest oxidative-stress resistant phenotypes of L. monocytogenes Bug600 and F1057. The sublethal H2O2 and sublethal alkali-stress induced oxidative-stress adaptations were completely reversible within 60 min at 37°C in the absence of such sublethal stress. However, the oxidative-stress adaptation induced at 37°C was stable at 4°C over a 24 h test period in both L. monocytogenes Bug600 and F1057. Future studies will focus on the potential cross-resistance of oxidative-stress adapted L. monocytogenes serotypes 1/2a and 4b to commonly used disinfectants and GRAS antimicrobials.
| Identifer | oai:union.ndltd.org:MSSTATE/oai:scholarsjunction.msstate.edu:td-3325 |
| Date | 14 December 2013 |
| Creators | De Abrew Abeysundara, Piumi |
| Publisher | Scholars Junction |
| Source Sets | Mississippi State University |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | Theses and Dissertations |
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