Stress Responses Of Foodborne Pathogens

Food-borne bacterial pathogens encounter a number of stressors during food processing and preservation. More and more pathogens are able to adapt their physiological properties and/or genetic expression to survive these stressors and pose a risk to food safety and public health. This book provides the reader with a comprehensive overview of common food processing-associated stressors (e.g., heat, cold, acid, osmosis, and oxidation) and deals with the molecular basis of the respective bacterial stress response mechanisms (e.g., viable but nonculturable state, biofilm formation, sporulation, and cross-protection response). Additionally, various chapters cover the response mechanisms of foodborne pathogens to emerging nonthermal sterilisation technologies such as ultrasound, high-pressure processing, pulsed electric fields, ultraviolet light, irradiation and phytochemicals. Through this book we also learn about future prospects for the efficient control of stress adaption in foodborne pathogens to ensure maximum consumer safety. This book offers a valuable resource for researchers, graduate students, food process engineers and product developers in the fields of food science and microbiology.

Knowledge of the responses of micro-organisms to environmental stresses has led to tremendous advances in the their morphological, physiological and genetic regulation, following the introduction of novel research techniques and the efforts of food microbiologists, microbial ecologists, molecular biologists and researchers in other fields. This book is primarily targeted at food microbiologists, microbial ecologists and other professionals in academia, industry and governmental agencies. In addition, this book is a useful reference in improving the processing of food and detecting micro-organisms therein.

Throughout the food processing chain and after ingestion by the host, food associated bacteria have to cope with a range of stress factors such as thermal and/or non-thermal inactivation treatments, refrigeration temperatures, freeze-drying, high osmolarity, acid pH in the stomach or presence of bile salts in the intestine, that threaten bacterial survival. The accompanying plethora of microbial response and adaptation phenomena elicited by these stresses has important implications for food technology and safety. Indeed, while resistance development of pathogenic and spoilage microorganisms may impose health risks for the consumer and impart great economic losses to food industries, reduced survival of probiotic bacteria may strongly compromise their claimed health benefit attributes. As a result, substantial research efforts have been devoted in the last decades to unravel the mechanisms underlying stress response and resistance development in food associated microorganisms in order to better predict and improve (i) the inactivation of foodborne pathogens and spoilage microorganisms on the one hand and (ii) the robustness and performance of beneficial microorganisms on the other. Moreover, the recent implementation of system-wide omics and (single-)cell biology approaches is greatly boosting our insights into the modes of action underlying microbial inactivation and survival. This Research Topic aims to provide an avenue for dissemination of recent advances within the field of microbial stress response and adaptation, with a particular focus not only on food spoilage and pathogenic microorganisms but also on beneficial microbes in foods.

Throughout the food processing chain and after ingestion by the host, food associated bacteria have to cope with a range of stress factors such as thermal and/or non-thermal inactivation treatments, refrigeration temperatures, freeze-drying, high osmolarity, acid pH in the stomach or presence of bile salts in the intestine, that threaten bacterial survival. The accompanying plethora of microbial response and adaptation phenomena elicited by these stresses has important implications for food technology and safety. Indeed, while resistance development of pathogenic and spoilage microorganisms may impose health risks for the consumer and impart great economic losses to food industries, reduced survival of probiotic bacteria may strongly compromise their claimed health benefit attributes. As a result, substantial research efforts have been devoted in the last decades to unravel the mechanisms underlying stress response and resistance development in food associated microorganisms in order to better predict and improve (i) the inactivation of foodborne pathogens and spoilage microorganisms on the one hand and (ii) the robustness and performance of beneficial microorganisms on the other. Moreover, the recent implementation of system-wide omics and (single-)cell biology approaches is greatly boosting our insights into the modes of action underlying microbial inactivation and survival. This Research Topic aims to provide an avenue for dissemination of recent advances within the field of microbial stress response and adaptation, with a particular focus not only on food spoilage and pathogenic microorganisms but also on beneficial microbes in foods.

Beginning with the basics of lactic acid bacteria and stress response, then working into specific fields of research and current developments, Stress Responses of Lactic Acid Bacteria will serve as an essential guidebook to researchers in the field, industry professionals, and advanced students in the area. The exploration of stress responses in lactic acid bacteria began in the early 90s and revealed the differences that exist between LAB and the classical model microorganisms. A considerable amount of work has been performed on the main genera / species of LAB regarding the genes implicated and their actual role and regulation, and the mechanisms of stress resistance have also been elucidated. Recent genome and transcriptome analyses complement the proteome and genetic information available today and shed a new light on the perception of and the responses to stress by lactic acid bacteria.

The contamination of the environment by herbicides, pesticides, solvents, various industrial byproducts (including toxic metals, radionucleotides and metalloids) is of enormous economic and environmental significance. Biotechnology can be used to develop "green" or environmentally friendly solutions to these problems by harnessing the ability of bacteria to adapt metabolic pathways, or recruit new genes to metabolise harmful compounds into harmless byproducts. In addition to its role in cleaning-up the environment, biotechnology can be used for the production of novel compounds with both agricultural and industrial applications. Internationally acclaimed authors from diverse fields present comprehensive reviews of all aspects of Industrial and Environmental Biotechnology. Chapters concerned with environmental biotechnology cover two major categories of pollutants: organic compounds and metals. Organic pollutants include cyclic aromatic compounds, with/without nitrogenous or chloride substitutions while metal pollutants include copper, chromate, silver, arsenic and mercury. The genetic basis of bioremediation and the microbial processes involved are examined, and the current and/or potential applications of bioremediation are discussed. The use of biotechnology for industrial and agricultural applications includes a chapter on the use of enzymes as biocatalysts to synthesize novel opiate derivatives of medical value. The conversion of low-value molasses to higher value products by biotechnological methods and the use tissue culture methods to improve sugar cane and potatoes crop production is discussed.

The first book to address the subject, Microbial Stress Adaptation and Food Safety emphasizes the implications of stress adaptation and its consequences for food safety. It covers the basic science, kinetics, mechanisms, assessment, and control of stress adaptation and its impact on the safety of foods produced by minimal processing or non-thermal technologies. World renowned experts in the field provide detailed accounts of problems associated with stress adaptation and suggest methods for overcoming these problems. The book begins with an introduction to the stress adaptation phenomenon and its implications for the safety of food processed by novel technologies. Then it addresses the responses of pathogens to physical and chemical stresses encountered during food processing, such as heat, pressure, dehydration, radiation, added organic acids, and naturally occurring antimicrobials. The adaptation of food microbiota to stress as a survival strategy is covered next, followed by an examination of the broad spectrum of stresses that may increase a pathogen's tenacity and resistance to processing. Other topics include stress adaptation of beneficial lactic acid bacteria and how resistance or adaptation to stress in the processing environment relates to pathogens' ability to cause disease. Finally, the book presents strategies to overcome stress adaptation in foodborne pathogens. The authors suggest practical control measures and emphasize the need for future research to counteract the stress adaptation phenomenon. Microbial Stress Adaptation and Food Safety proposes practical solutions to microbial stress adaptation and its hazardous effects on food safety and human health.

Pathogens respond dynamically to their environment. Understanding their behaviour is critical both because of evidence of increased resistance to established sanitation and preservation techniques, and because of the increased use of minimal processing technologies which are more vulnerable to the development of resistance. Understanding pathogen behaviour summarises the wealth of recent research and its implications for the food industry. After two introductory chapters on ways of analysing and modelling pathogens, Part one summarises current research on what determines pathogenicity, stress response, adaptation and resistance. Part two reviews the behaviour of particular pathogens, reviewing virulence, stress response and resistance mechanisms in such pathogens as Salmonella, E.coli and Campylobacter. The final part of the book assesses how pathogens react and adapt to particular stresses from heat treatment and the effects of low temperature to the use of disinfectants and sanitisers. With its distinguished editor and international team of contributors, Understanding pathogen behaviour is a standard reference for the food industry in ensuring food safety. Summarises the wealth of recent research in pathogen behaviour Assesses implications for microbiologists and QA staff in the food industry