נגישות
menu      
Advanced Search
Gruzdev, N., Microbial Food-Safety Research Unit, Department of Food Quality and Safety, Institute for Technology and Storage of Agricultural Products, Agricultural Research Organization (ARO), The Volcani Center, POB 6, Beth-Dagan 5025, Israel, Department of Biochemistry and Food Science, Robert H. Smith Faculty of Agriculture, Food, and Environment, The Hebrew University, Rehovot, Israel
Pinto, R., Microbial Food-Safety Research Unit, Department of Food Quality and Safety, Institute for Technology and Storage of Agricultural Products, Agricultural Research Organization (ARO), The Volcani Center, POB 6, Beth-Dagan 5025, Israel
Sela, S., Microbial Food-Safety Research Unit, Department of Food Quality and Safety, Institute for Technology and Storage of Agricultural Products, Agricultural Research Organization (ARO), The Volcani Center, POB 6, Beth-Dagan 5025, Israel
Reducing the available water in food is a long-established method for controlling bacterial growth in the food industry. Nevertheless, food-borne outbreaks of salmonellosis due to consumption of dry foods have been continuously reported. Previous studies showed that dried Salmonella cells acquire high tolerance to heat and ethanol. In order to examine if dehydration also induces tolerance to other stressors, dried Salmonella enterica serotype Typhimurium cells were exposed to multiple stresses, and their viability was assessed. Indeed, desiccated S. Typhimurium acquired higher tolerance to multiple stressors than nondesiccated cells. The dried cells were significantly more resistant to most stressors, including ethanol (10 to 30%, 5 min), sodium hypochlorite (10 to 100 ppm, 10 min), didecyl dimethyl ammonium chloride (0.05 to 0.25%, 5 min), hydrogen peroxide (0.5 to 2.0%, 30 min), NaCl (0.1 to 1 M, 2 h), bile salts (1 to 10%, 2 h), dry heat (100°C, 1 h), and UV irradiation (125 μW/cm2, 25 min). In contrast, exposure of Salmonella to acetic and citric acids reduced the survival of the dried cells (1.5 log) compared to that of nondesiccated cells (0.5 log). Three other S. enterica serotypes, S. Enteritidis, S. Newport, and S. Infantis, had similar stress responses as S. Typhimurium, while S. Hadar was much more susceptible and gained tolerance to only a few stressors. Our findings indicate that dehydration induces cross-tolerance to multiple stresses in S. enterica, demonstrating the limitations of current chemical and physical treatments utilized by the food industry to inactivate food-borne pathogens. © 2011, American Society for Microbiology.
Powered by ClearMash Solutions Ltd -
Volcani treasures
About
Terms of use
Effect of desiccation on tolerance of Salmonella enterica to multiple stresses
77
Gruzdev, N., Microbial Food-Safety Research Unit, Department of Food Quality and Safety, Institute for Technology and Storage of Agricultural Products, Agricultural Research Organization (ARO), The Volcani Center, POB 6, Beth-Dagan 5025, Israel, Department of Biochemistry and Food Science, Robert H. Smith Faculty of Agriculture, Food, and Environment, The Hebrew University, Rehovot, Israel
Pinto, R., Microbial Food-Safety Research Unit, Department of Food Quality and Safety, Institute for Technology and Storage of Agricultural Products, Agricultural Research Organization (ARO), The Volcani Center, POB 6, Beth-Dagan 5025, Israel
Sela, S., Microbial Food-Safety Research Unit, Department of Food Quality and Safety, Institute for Technology and Storage of Agricultural Products, Agricultural Research Organization (ARO), The Volcani Center, POB 6, Beth-Dagan 5025, Israel
Effect of desiccation on tolerance of Salmonella enterica to multiple stresses
Reducing the available water in food is a long-established method for controlling bacterial growth in the food industry. Nevertheless, food-borne outbreaks of salmonellosis due to consumption of dry foods have been continuously reported. Previous studies showed that dried Salmonella cells acquire high tolerance to heat and ethanol. In order to examine if dehydration also induces tolerance to other stressors, dried Salmonella enterica serotype Typhimurium cells were exposed to multiple stresses, and their viability was assessed. Indeed, desiccated S. Typhimurium acquired higher tolerance to multiple stressors than nondesiccated cells. The dried cells were significantly more resistant to most stressors, including ethanol (10 to 30%, 5 min), sodium hypochlorite (10 to 100 ppm, 10 min), didecyl dimethyl ammonium chloride (0.05 to 0.25%, 5 min), hydrogen peroxide (0.5 to 2.0%, 30 min), NaCl (0.1 to 1 M, 2 h), bile salts (1 to 10%, 2 h), dry heat (100°C, 1 h), and UV irradiation (125 μW/cm2, 25 min). In contrast, exposure of Salmonella to acetic and citric acids reduced the survival of the dried cells (1.5 log) compared to that of nondesiccated cells (0.5 log). Three other S. enterica serotypes, S. Enteritidis, S. Newport, and S. Infantis, had similar stress responses as S. Typhimurium, while S. Hadar was much more susceptible and gained tolerance to only a few stressors. Our findings indicate that dehydration induces cross-tolerance to multiple stresses in S. enterica, demonstrating the limitations of current chemical and physical treatments utilized by the food industry to inactivate food-borne pathogens. © 2011, American Society for Microbiology.
Scientific Publication
You may also be interested in