The Role Of Biofilms In The Development And Dissemination Of Microbial Resistance Within The Food Industry

Biofilms are multicellular sessile microbial communities embedded in hydrated extracellular polymeric matrices. Their formation is common in microbial life in most environments, whereas those formed on food-processing surfaces are of considerable interest in the context of food hygiene. Biofilm cells express properties that are distinct from planktonic ones, in particular, due to their notorious resistance to antimicrobial agents. Thus, a special feature of biofilms is that once they have developed, they are hard to eradicate, even when careful sanitization procedures are regularly applied. A large amount of ongoing research has investigated how and why surface-attached microbial communities develop such resistance, and several mechanisms can be acknowledged, such as heterogeneous metabolic activity, cell adaptive responses, diffusion limitations, genetic and functional diversification, and microbial interactions. The articles contained in this Special Issue deal with biofilms of some important food-related bacteria (including common pathogens such as Salmonella enterica, Listeria monocytogenes, and Staphylococcus aureus, as well as spoilage-causing spore-forming bacilli), providing novel insights into their resistance mechanisms and implications, together with novel methods (e.g., use of protective biofilms formed by beneficial bacteria, enzymes) that could be used to overcome resistance and thus improve the safety of our food supply and protect public health.

Biofilms are multicellular sessile microbial communities embedded in hydrated extracellular polymeric matrices. Their formation is common in microbial life in most environments, whereas those formed on food-processing surfaces are of considerable interest in the context of food hygiene. Biofilm cells express properties that are distinct from planktonic ones, in particular, due to their notorious resistance to antimicrobial agents. Thus, a special feature of biofilms is that once they have developed, they are hard to eradicate, even when careful sanitization procedures are regularly applied. A large amount of ongoing research has investigated how and why surface-attached microbial communities develop such resistance, and several mechanisms can be acknowledged, such as heterogeneous metabolic activity, cell adaptive responses, diffusion limitations, genetic and functional diversification, and microbial interactions. The articles contained in this Special Issue deal with biofilms of some important food-related bacteria (including common pathogens such as Salmonella enterica, Listeria monocytogenes, and Staphylococcus aureus, as well as spoilage-causing spore-forming bacilli), providing novel insights into their resistance mechanisms and implications, together with novel methods (e.g., use of protective biofilms formed by beneficial bacteria, enzymes) that could be used to overcome resistance and thus improve the safety of our food supply and protect public health.

Materials and equipment in food processing industries are colonized by surface-associated microbial communities called biofilms. In these biostructures microorganisms are embedded in a complex organic matrix composed essentially of polysaccharides, nucleic acids and proteins. This organic shield contributes to the mechanical biofilm cohesion and triggers tolerance to environmental stresses such as dehydratation or nutrient deprivation. Notably, cells within a biofilm are more tolerant to sanitation processes and the action of antimicrobial agents than their free living (or planktonic) counterparts. Such properties make conventional cleaning and disinfection protocols normally not effective in eradicating these biocontaminants. Biofilms are thus a continuous source of persistent microorganisms, including spoilage and pathogenic microorganisms, leading to repeated contamination of processed food with important economic and safety impact. Alternatively, in some particular settings, biofilm formation by resident or technological microorganisms can be desirable, due to possible enhancement of food fermentations or as a means of bioprotection against the settlement of pathogenic microorganisms. In the last decades substantial research efforts have been devoted to unravelling mechanisms of biofilm formation, deciphering biofilm architecture and understanding microbial interactions within those ecosystems. However, biofilms present a high level of complexity and many aspects remain yet to be fully understood. A lot of attention has been also paid to the development of novel strategies for preventing or controlling biofilm formation in industrial settings. Further research needs to be focused on the identification of new biocides effective against biofilm-associated microorganisms, the development of control strategies based on the inhibition of cell-to-cell communication, and the potential use of bacteriocins, bacteriocin-producing bacteria, phage, and natural antimicrobials as anti-biofilm agents, among others. This Research Topic aims to provide an avenue for dissemination of recent advances within the “biofilms” field, from novel knowledge on mechanisms of biofilm formation and biofilm architecture to novel strategies for biofilm control in food industrial settings.

In nature, microorganisms are generally found attached to surfaces as biofilms such as dust, insects, plants, animals and rocks, rather than suspended in solution. Once a biofilm is developed, other microorganisms are free to attach and benefit from this microbial community. The food industry, which has a rich supply of nutrients, solid surfaces, and raw materials constantly entering and moving through the facility, is an ideal environment for biofilm development, which can potentially protect food pathogens from sanitizers and result in the spread of foodborne illness. Biofilms in the Food Environment is designed to provide researchers in academia, federal research labs, and industry with an understanding of the impact, control, and hurdles of biofilms in the food environment. Key to biofilm control is an understanding of its development. The goal of this 2nd edition is to expand and complement the topics presented in the original book. Readers will find: The first comprehensive review of biofilm development by Campylobacter jejuni An up-date on the resistance of Listeria monocytogenes to sanitizing agents, which continues to be a major concern to the food industry An account of biofilms associated with various food groups such as dairy, meat, vegetables and fruit is of global concern A description of two novel methods to control biofilms in the food environment: bio-nanoparticle technology and bacteriophage Biofilms are not always a problem: sometimes they even desirable. In the human gut they are essential to our survival and provide access to some key nutrients from the food we consume. The authors provide up-date information on the use of biofilms for the production of value-added products via microbial fermentations. Biofilms cannot be ignored when addressing a foodborne outbreak. All the authors for each chapter are experts in their field of research. The Editors hope is that this second edition will provide the bases and understanding for much needed future research in the critical area of Biofilm in Food Environment.

Materials and equipment in food processing industries are colonized by surface-associated microbial communities called biofilms. In these biostructures microorganisms are embedded in a complex organic matrix composed essentially of polysaccharides, nucleic acids and proteins. This organic shield contributes to the mechanical biofilm cohesion and triggers tolerance to environmental stresses such as dehydratation or nutrient deprivation. Notably, cells within a biofilm are more tolerant to sanitation processes and the action of antimicrobial agents than their free living (or planktonic) counterparts. Such properties make conventional cleaning and disinfection protocols normally not effective in eradicating these biocontaminants. Biofilms are thus a continuous source of persistent microorganisms, including spoilage and pathogenic microorganisms, leading to repeated contamination of processed food with important economic and safety impact. Alternatively, in some particular settings, biofilm formation by resident or technological microorganisms can be desirable, due to possible enhancement of food fermentations or as a means of bioprotection against the settlement of pathogenic microorganisms. In the last decades substantial research efforts have been devoted to unravelling mechanisms of biofilm formation, deciphering biofilm architecture and understanding microbial interactions within those ecosystems. However, biofilms present a high level of complexity and many aspects remain yet to be fully understood. A lot of attention has been also paid to the development of novel strategies for preventing or controlling biofilm formation in industrial settings. Further research needs to be focused on the identification of new biocides effective against biofilm-associated microorganisms, the development of control strategies based on the inhibition of cell-to-cell communication, and the potential use of bacteriocins, bacteriocin-producing bacteria, phage, and natural antimicrobials as anti-biofilm agents, among others. This Research Topic aims to provide an avenue for dissemination of recent advances within the "biofilms" field, from novel knowledge on mechanisms of biofilm formation and biofilm architecture to novel strategies for biofilm control in food industrial settings.

Biofilms in the Food Environment examines biofilms produced by food-borne microorganisms, the risks associated with biofilms in the food chain, the beneficial applications of biofilms in the food environment, and approaches for biofilm removal to improve sanitation and safety in the food environment. Specifically, this book provides: an introduction into the emerging and exciting field of biofilm research in the food environment a summary of advanced knowledge in medical microbiology and engineering and its applicability to food biofilm research, and potential directions for biofilm intervention and industrial beneficial applications that may have direct impact on food safety and public health. Biofilms in the Food Environment is intended to serve as a comprehensive reference source for the food science community, including industry scientists, university researchers, and regulatory agencies. Not only are general concepts regarding biofilms in the food environment covered, but also included are in-depth reviews on biofilm structures, the correlation between strain virulence and biofilm-forming abilities, cutting-edge technologies to investigate microbial compositions in ecosystems and cell-to-cell interactions, and updated findings on molecular attributes and mechanisms involved in biofilm development that might lead to targeted approaches for biofilm prevention and removal. The topics covered and approaches discussed are truly interdisciplinary in nature.

Throughout the biological world, bacteria thrive predominantly in surface-attached, matrix-enclosed, multicellular communities or biofilms, as opposed to isolated planktonic cells. This choice of lifestyle is not trivial, as it involves major shifts in the use of genetic information and cellular energy, and has profound consequences for bacterial physiology and survival. Growth within a biofilm can thwart immune function and antibiotic therapy and thereby complicate the treatment of infectious diseases, especially chronic and foreign device-associated infections. Modern studies of many important biofilms have advanced well beyond the descriptive stage, and have begun to provide molecular details of the structural, biochemical, and genetic processes that drive biofilm formation and its dispersion. There is much diversity in the details of biofilm development among various species, but there are also commonalities. In most species, environmental and nutritional conditions greatly influence biofilm development. Similar kinds of adhesive molecules often promote biofilm formation in diverse species. Signaling and regulatory processes that drive biofilm development are often conserved, especially among related bacteria. Knowledge of such processes holds great promise for efforts to control biofilm growth and combat biofilm-associated infections. This volume focuses on the biology of biofilms that affect human disease, although it is by no means comprehensive. It opens with chapters that provide the reader with current perspectives on biofilm development, physiology, environmental, and regulatory effects, the role of quorum sensing, and resistance/phenotypic persistence to antimicrobial agents during biofilm growth.

Bacterial biofilms are colonies of bacterial cells embedded in their self-produced matrix composed of polysaccharides, DNA, and proteins. They protect bacterial cells against antibiotics, antibacterial agents, soaps and detergents, and shear stress. Some of the most common biofilm-associated infections in humans include urinary tract infections, infection of wounds and surgical sites, diabetic foot ulcers, dental caries (tooth decay) and gingivitis (gum inflammation), ventilator-associated infections, sinusitis, microbial keratitis, secondary infection related to Covid-19 and other viral infections, and so on. Bacterial resistance to common antibiotics (e.g., penicillin, gentamycin, erythromycin, ciprofloxacin, etc.) is driving us to a catastrophic failure of our health systems. Strategies to develop novel antibacterial agents and technology must be prioritized to combat and eradicate biofilms and their associated challenges. This book provides a comprehensive overview of biofilms with chapters on bacterial virulence factors, quorum sensing in bacteria, antimicrobial resistance in bacteria, strategies to develop new antibacterial agents, and much more.