title: Induction and stability of oxidative stress adaptation in Listeria monocytogenes EGD (Bug600) and F1057 in sublethal concentrations of H2O2and NaOH.
abstract: Food processing and food handling environments may contain residual levels of sanitizers or cleaners which may trigger oxidative stress adaptation in Listeria monocytogenes. The aim of this study was to determine the induction and stability of oxidative stress adaptation in L. monocytogenes EGD (Bug600) (serotype 1/2a) and F1057 (serotype 4b) at different concentrations and times of sublethal oxidative stress induced by H2O2or sublethal alkali stress induced by NaOH at 37°C. Both L. monocytogenes Bug600 and F1057 strains showed significantly higher survival in lethal oxidative stress (1000ppm H2O2) after pre-exposure to 50ppm H2O2for 30min compared to control cells (no pre-exposure to H2O2). When the cells were pre-exposed to sublethal alkali stress by NaOH, the oxidative stress adaptation was induced within 5min in L. monocytogenes. The survival of both L. monocytogenes strains was increased by 2 to 4.5 logs in lethal oxidative stress when the cells were pre-exposed to sublethal alkali stress at pH9 from 5 to 120min by NaOH compared to control cells (no pre-exposure to sublethal alkali pH). Two other alkali reagents tested (KOH and NH4OH) also induced oxidative stress adaptation in L. monocytogenes. For both L. monocytogenes strains, the oxidative stress adaptation induced by sublethal H2O2was reversible in 30min and that induced by sublethal alkali stress was reversible within 60min at 37°C in the absence of such sublethal stress. These findings show that sublethal oxidative or alkali stress conditions can induce oxidative stress adaptation that may increase the risk of survival of L. monocytogenes cells in lethal oxidative stress.
authors.affiliation: Department of Food Science, Nutrition and Health Promotion, Mississippi State University, Mississippi State, MS 39762, USA.
authors.forename: Piumi
authors.initials: P
authors.lastname: De Abrew Abeysundara
authors.affiliation: Department of Food Science, Nutrition and Health Promotion, Mississippi State University, Mississippi State, MS 39762, USA. Electronic address: nannapaneni@fsnhp.msstate.edu.
authors.forename: Ramakrishna
authors.initials: R
authors.lastname: Nannapaneni
authors.affiliation: Department of Food Science, Nutrition and Health Promotion, Mississippi State University, Mississippi State, MS 39762, USA.
authors.forename: Kamlesh A
authors.initials: KA
authors.lastname: Soni
authors.affiliation: Poultry Science Department, Mississippi State University, Mississippi State, MS 39762, USA.
authors.forename: Chander S
authors.initials: CS
authors.lastname: Sharma
authors.affiliation: Department of Food Science, Nutrition and Health Promotion, Mississippi State University, Mississippi State, MS 39762, USA.
authors.forename: Barakat
authors.initials: B
authors.lastname: Mahmoud
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects; D000641:Ammonia / Q000494:pharmacology*; D005511:Food Handling; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D006863:Hydrogen-Ion Concentration; D006878:Hydroxides / Q000494:pharmacology*; D008089:Listeria monocytogenes / Q000187:drug effects*; D018384:Oxidative Stress / Q000187:drug effects*; D017680:Potassium Compounds / Q000494:pharmacology*; D012972:Sodium Hydroxide / Q000494:pharmacology*
chemical_list: D006878:Hydroxides; D017680:Potassium Compounds; D012972:Sodium Hydroxide; D000641:Ammonia; D006861:Hydrogen Peroxide; C029943:potassium hydroxide
keywords: Alkali stress; Listeria monocytogenes; Oxidative stress; Stress adaptation; Sublethal stress