Theses and Dissertations

Issuing Body

Mississippi State University

Advisor

Nannapaneni, Ramakrishna

Committee Member

Schilling, M. Wes

Committee Member

Kim, Taejo

Committee Member

Sharma, Chander Shekhar

Committee Member

Haque, Zahur Z.

Date of Degree

1-1-2013

Document Type

Graduate Thesis - Open Access

Abstract

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.

URI

https://hdl.handle.net/11668/18875

Share

COinS