Download or read book Heat and Pressure Resistance of Escherichia Coli and Its Inactivation in the Presence of Antimicrobial Compounds written by Yang Liu and published by . This book was released on 2014 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt: Verotoxigenic Escherichia coli (VTEC) are pathogens causing severe foodborne disease. E. coli AW1.7 is a heat resistant beef carcass isolate that may be used as a surrogate organism to study the survival of VTEC on food. This dissertation examines the heat and pressure resistance of E. coli and the application of antimicrobial compounds to achieve its inactivation in food. The pressure resistance of E. coli AW1.7 was compared to the resistance of other foodborne pathogens and spoilage organisms relevant in meat. E. coli AW1.7 was the most pressure resistant organism tested. Moreover, the ability of E. coli AW1.7 to resist pressure was comparable to the pressure-resistant mutant E. coli LMM1030. To further study the heat- and pressure resistance of E. coli, E. coli AW1.7 was compared to the heat- and pressure resistance of VTEC strains from different serotypes and phylotypes. E. coli AW1.7 exhibited a higher heat resistance than VTEC strains; however, some VTEC strains also survived in hamburgers grilled to a core temperature of 71°C. Several strains of VTEC exhibited a higher resistance to pressure than E. coli AW1.7. Over one third of tested strains showed 3 log CFU/g or less cell count reduction under high pressure treatment of 600 MPa for 3 min. Therefore, additional treatment processes are required for elimination of VTEC in pressure treated food. Additional treatments were evaluated to achieve the elimination of E. coli in buffers and food matrices. Chitosan was effective in injury E. coli in imidazole and potassium phosphate buffer; chitosan, nisin and lactate combination were effective in yogurt serum; chitosan, nisin and heat were effective in apple juice; and chitosan, Micocin® X and heat had small bactericidal effects in ground beef. A combination of chitosan and high pressure was not effective against E. coli AW1.7 in potassium phosphate buffer, but addition of Micocin® X to increased killing of E. coli AW1.7. In conclusion, this thesis demonstrated that high pressure alone is insufficient to kill E. coli in meat. Bacteriocins, lactate, and chitosan can be applied as additional antimicrobial treatments to kill E. coli in food. And the bactericidal effect is strongly dependent on the food matrix and the preservation method. Some of the VTEC strains tested survived heat treatment and high hydrostatic pressure (HHP) permitted recommendations of E. coli by Canadian regulatory agencies (Health Canada and Canadian Food Inspection Agency). More studies need to be conducted to validate the results.
Download or read book Mechanisms of antibiotic resistance written by Jun Lin and published by Frontiers Media SA. This book was released on 2015-06-01 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: Antibiotics represent one of the most successful forms of therapy in medicine. But the efficiency of antibiotics is compromised by the growing number of antibiotic-resistant pathogens. Antibiotic resistance, which is implicated in elevated morbidity and mortality rates as well as in the increased treatment costs, is considered to be one of the major global public health threats (www.who.int/drugresistance/en/) and the magnitude of the problem recently prompted a number of international and national bodies to take actions to protect the public (http://ec.europa.eu/dgs/health_consumer/docs/road-map-amr_en.pdf: http://www.who.int/drugresistance/amr_global_action_plan/en/; http://www.whitehouse.gov/sites/default/files/docs/carb_national_strategy.pdf). Understanding the mechanisms by which bacteria successfully defend themselves against the antibiotic assault represent the main theme of this eBook published as a Research Topic in Frontiers in Microbiology, section of Antimicrobials, Resistance, and Chemotherapy. The articles in the eBook update the reader on various aspects and mechanisms of antibiotic resistance. A better understanding of these mechanisms should facilitate the development of means to potentiate the efficacy and increase the lifespan of antibiotics while minimizing the emergence of antibiotic resistance among pathogens.
Download or read book The Effects on Human Health of Subtherapeutic Use of Antimicrobials in Animal Feeds written by National Research Council and published by National Academies Press. This book was released on 1980-02-01 with total page 393 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Variation in Resistance to High Hydrostatic Pressure of Escherichia Coli written by Rigoberto Garcia-Hernandez and published by . This book was released on 2016 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: Verotoxigenic Escherichia coli (VTEC) pose a risk for foodborne illness that can lead to death. Thermal food preservation to inactivate VTEC also alters food quality. High hydrostatic pressure (HHP) processing has been adopted by the food industry as an alternative to thermal preservation. However, E. coli exhibits great variability in resistance to pressure. This research evaluated the pressure resistance of VTEC and non-VTEC E. coli in laboratory media and ground beef. A strain cocktail of non-pathogenic E. coli was developed to match the pressure resistance of VTEC. The strain cocktail was validated by pressure treatments in ground beef and vegetable products. Pressure resistance of E. coli is affected by the food matrix. Therefore, the effect of the food matrix and food constituents on pressure resistance of E. coli was determined. Ground beef showed a baro-protective effect on E. coli when compared to treatments in bruschetta and tzatziki at the same pH (5.5). Divalent cations (Ca2+) exerted a baroprotective effect and may partially explain the relative resistance of E. coli in ground beef. To further elucidate mechanisms of pressure resistance, four extremely pressure resistant strains of E. coli, including one VTEC, were generated and cross-resistance to other stressors was evaluated. All four strains of E. coli evolved as extremely pressure resistant strains when treated with consecutive cycles of increasing pressure. Derivative E. coli AW1.7 became sensitive to low pH (2.5) and derivative E. coli AW1.3 exhibited increased resistance to heat and osmotic stress. Comparative analysis of the genome sequence of 3 wild type strains to the respective pressure-resistant revealed that derivative strains exhibited deletion of genetic elements. However, deletions were different without apparent consistency among the strains. In conclusion, the species E. coli contains extremely pressure resistant strains that are not readily inactivated by pressure treatment of food. Knowledge on the strain/matrix interaction during and after pressure treatment will facilitate the design, adoption, and/or combination of different intervention methods to warrant food safety.
Download or read book Industrial and Host Associated Stress Responses in Food Microbes Implications for Food Technology and Food Safety written by Lorena Ruiz and published by Frontiers Media SA. This book was released on 2017-10-19 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book E Coli Infections written by Luis Rodrigo and published by BoD – Books on Demand. This book was released on 2020-09-30 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gram-negative Escherichia coli (E. coli) bacteria are the most numerous commensal aerobic germs located in the human colon. Diarrhea caused by E. coli pathogenic strains is a major cause of death in developing countries, especially the sub-Saharan and South Asian areas. Some strains cause diarrhea, and all of them may produce an infectious disease. This book includes ten chapters covering the main aspects of infections related to E. coli, their pathogenic mechanisms, treatments, and resistance to diverse antibiotics.
Download or read book Non thermal Processing of Foods written by O. P. Chauhan and published by CRC Press. This book was released on 2019-01-10 with total page 462 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the latest developments in the area of non-thermal preservation of foods and covers various topics such as high-pressure processing, pulsed electric field processing, pulsed light processing, ozone processing, electron beam processing, pulsed magnetic field, ultrasonics, and plasma processing. Non-thermal Processing of Foods discusses the use of non-thermal processing on commodities such as fruits and vegetables, cereal products, meat, fish and poultry, and milk and milk products. Features: Provides latest information regarding the use of non-thermal processing of food products Provides information about most of the non-thermal technologies available for food processing Covers food products such as fruits and vegetables, cereal products, meat, fish and poultry, and milk and milk products Discusses the packaging requirements for foods processed with non-thermal techniques The effects of non-thermal processing on vital food components, enzymes and microorganisms is also discussed. Safety aspects and packaging requirements for non-thermal processed foods are also presented. Rounding out coverage of this technology are chapters that cover commercialization, regulatory issues and consumer acceptance of foods processed with non-thermal techniques. The future trends of non-thermal processing are also investigated. Food scientists and food engineers, food regulatory agencies, food industry personnel and academia (including graduate students) will find valuable information in this book. Food product developers and food processors will also benefit from this book.
Download or read book Bacterial Persistence written by Jan Michiels and published by Humana. This book was released on 2015-10-15 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents a comprehensive collection of methods that have been instrumental to the current understanding of bacterial persisters. Chapters in the book cover topics ranging from general methods for measuring persister levels in Escherichia coli cultures, protocols for the determination of the persister subpopulation in Candida albicans, quantitative measurements of Type I and Type II persisters using ScanLag, to in vitro and in vivo models for the study of the intracellular activity of antibiotics. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and cutting-edge, Bacterial Persistence: Methods and Protocols brings together the most respected researchers in bacterial persistence whose studies will remain vital to understanding this field for many years to come.
Download or read book Microbial Evolution and Co Adaptation written by Institute of Medicine and published by National Academies Press. This book was released on 2009-05-10 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dr. Joshua Lederberg - scientist, Nobel laureate, visionary thinker, and friend of the Forum on Microbial Threats - died on February 2, 2008. It was in his honor that the Institute of Medicine's Forum on Microbial Threats convened a public workshop on May 20-21, 2008, to examine Dr. Lederberg's scientific and policy contributions to the marketplace of ideas in the life sciences, medicine, and public policy. The resulting workshop summary, Microbial Evolution and Co-Adaptation, demonstrates the extent to which conceptual and technological developments have, within a few short years, advanced our collective understanding of the microbiome, microbial genetics, microbial communities, and microbe-host-environment interactions.
Download or read book Clinical Manual of Fever in Children written by A. Sahib El-Radhi and published by Springer. This book was released on 2019-01-01 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses the latest scientific evidence related to fever and presents the principles of clinical practice, covering different types of fever and its possible complications. The book adopts a clearly defined, practical and effective approach to the management of fever, helping the clinician improve the care for the febrile child. The reader will learn about the guidelines on antipyretics and their side-effects and differential diagnoses, with problem-setting and solving as a case presentation.The second edition of this well-received book has been fully updated to include exciting new information of the pathogenesis of fever, including functions of interleukin and all the latest guidelines from NICE and Cochrane Library, as well as all the most up-to-date information and guidelines on febrile seizures. This reader-friendly reference on the disorders of body temperature in children covers the entire spectrum of subjects related to fever. It gives an overview of the best treatment options in order to achieve the best results. Containing a core message at the start of each chapter and with and a reader-friendly format this is an indispensable guide for paediatricians, family doctors and other professionals who are regularly consulted because of febrile children.
Download or read book Food Microbiology written by K Vijaya Ramesh and published by MJP Publisher. This book was released on 2019-06-07 with total page 823 pages. Available in PDF, EPUB and Kindle. Book excerpt: Food Microbiology is the study of action of microbes on food. The book discusses in a narrative style, the interaction between microbes, food and the environment besides tracing the beneficial and harmful effects of microbial growth in food. The contents of the book have been sequentialy divided into 5 units giving a detailed account of the various aspects of food as an ecosystem, preservation techniques? both traditional and advanced, importance of microbial degradation and fermentation of food along with the prevalent food-borne diseases. The laboratory diagnosis of the food-borne pathogens and their isolation, identification and characterization would be useful for students, researchers and teachers.
Download or read book Photodynamic Inactivation of Microbial Pathogens written by Michael R Hamblin and published by Royal Society of Chemistry. This book was released on 2011-06-06 with total page 451 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photodynamic therapy (PDT) was discovered over one hundred years ago after observing the death of microorganisms upon exposure to dyes and light. It is the combination of non-toxic dyes and harmless visible light that, in the presence of oxygen, produce highly toxic reactive species. The principal medical application during the last century was in cancer therapy but, in these days of rising antibiotic resistance, PDT shows increasing promise as an alternative approach to treating infections. PDT has also been used in blood product sterilization, peridontology, acne reduction, and the treatment of viral lesions such as those caused by human papilloma virus. It may also have potential as an environmentally friendly pesticide. This is the first and only book to comprehensively cover the use of light and photosensitising agents for controlling microbial pathogens. It provides a comprehensive and up-to-date coverage of an emerging field. There are several chapters on the design of antimicrobial photosensitizers, their use to kill pathogenic organisms and their success in treating infections in animal models. It has long been known that gram-positive bacteria are highly susceptible to photoinactivation but the book also discusses means of widening the range of microorganisms that can be tackled by PDT. Edited by two pioneers in the application of PDT to medical and environmental issues, this book covers the basic science, translational research in animals, and the clinical applications in various medical specialities. It represents an indispensable resource for microbiologists and infectious disease doctors as well as dentists, dermatologists, gastroenterologists and transfusion specialists.
Download or read book Milk Processing and Quality Management written by Adnan Y. Tamime and published by John Wiley & Sons. This book was released on 2009-01-30 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Society of Dairy Technology (SDT) has joined with Wiley-Blackwell to produce a series of technical dairy-related handbooks providing an invaluable resource for all those involved in the dairy industry; from practitioners to technologists working in both traditional and modern large-scale dairy operations. The fifth volume in the series, Milk Processing and Quality Management, provides timely and comprehensive guidance on the processing of liquid milks by bringing together contributions from leading experts around the globe. This important book covers all major aspects of hygienic milk production, storage and processing and other key topics such as: Microbiology of raw and market milks Quality control International legislation Safety HACCP in milk processing All those involved in the dairy industry including food scientists, food technologists, food microbiologists, food safety enforcement personnel, quality control personnel, dairy industry equipment suppliers and food ingredient companies should find much of interest in this commercially important book which will also provide libraries in dairy and food research establishments with a valuable reference for this important area.
Download or read book Science and Technology Against Microbial Pathogens written by A. Méndez-Vilas and published by World Scientific. This book was released on 2011 with total page 447 pages. Available in PDF, EPUB and Kindle. Book excerpt: Antimicrobial susceptibility profile and effect of stem bark extracts of Curtisia dentata on multi-drug resistant verotoxic Escherichia coli and Acinetobacter spp. isolates obtained from water and wastewater samples / Hamuel James Doughari [und weitere]. Antimicrobial utilization in intensive care units of a private tertiary care hospital / Pramil Tiwari, Vani Yadav and Shilpi Singh. Bacterial clearance from blood in mice infected by S. pneumoniae (penicillin MIC = 16 ug/ml) presenting specific IgG (non-protective levels) and treated with sub-therapeutic regimens of cefditoren (a highly bound cephalosporin) / Fabio Cafini [und weitere]. Characterisation of methicillin resistant Staphylococcus aureus isolates from hospitalised patients / Vladimir Kmet, Daniela Ohlasova and Milan Niks. Characterization of methicillin-resistant coagulase-negative Staphylococci isolates from blood cultures in a Brazilian University Hospital / Valeria Cataneli Pereira and Maria de Lourdes Ribeiro de Souza da Cunha. Control of bacterial contamination in boar semen doses / J.M. Morrell and Margareta Wallgren. Diffusion of extended-spectrum B-lactamase producing Enterobacter cloacae in a kidney transplantation unit / S. Hammami [und weitere]. Effect of antifungal agents on non-Candida albicans Candida species enzymatic activity / M. Negri [und weitere]. Effect of chitosan, nisin and storage time on the growth of Listeria innocua and Shewanella putrefaciens in fish homogenates / L.I. Schelegueda, M.F. Gliemmo and C.A. Campos. ESBL-producing Enterobacteriaceae in the northern Portugal - antimicrobial susceptibility and molecular epidemiology / R. Fernandes and C. Prudencio. Observations on the antimicrobial susceptibility of Staphylococcus pseudintermedius following the introduction of cefovecin for clinical use in Europe / Y. Chaudhry, A. Robinson and K.S. Godinho. Oxacillin resistance among Staphylococcus aureus isolated from peritoneal dialysis related peritonitis / C.H. Camargo [und weitere]. Resistance detection and susceptibility profile in Staphylococcus spp. isolated from patients with urinary tract infection (UTI) / Adriano Martison Ferreira [und weitere]. Resistance distribution profile of MBL, ESBL and multidrug resistant Gram negatives isolated at a tertiary care hospital in India / K.H. Bhutada and V.R. Shende
Download or read book Bacterial Pathogenesis written by and published by Academic Press. This book was released on 1998-07-01 with total page 643 pages. Available in PDF, EPUB and Kindle. Book excerpt: Established almost 30 years ago, Methods in Microbiology is the most prestigious series devoted to techniques and methodology in the field. Now totally revamped, revitalized, with a new format and expanded scope, Methods in Microbiology will continue to provide you with tried and tested, cutting-edge protocols to directly benefit your research. - Focuses on the methods most useful for the microbiologist interested in the way in which bacteria cause disease - Includes section devoted to 'Approaches to characterising pathogenic mechanisms' by Stanley Falkow - Covers safety aspects, detection, identification and speciation - Includes techniques for the study of host interactions and reactions in animals and plants - Describes biochemical and molecular genetic approaches - Essential methods for gene expression and analysis - Covers strategies and problems for disease control
Download or read book New Methods of Food Preservation written by G. W. Gould and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stress and Environmental Regulation of Gene Expression and Adaptation in Bacteria written by Frans J. de Bruijn and published by John Wiley & Sons. This book was released on 2016-07-01 with total page 1464 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bacteria in various habitats are subject to continuously changing environmental conditions, such as nutrient deprivation, heat and cold stress, UV radiation, oxidative stress, dessication, acid stress, nitrosative stress, cell envelope stress, heavy metal exposure, osmotic stress, and others. In order to survive, they have to respond to these conditions by adapting their physiology through sometimes drastic changes in gene expression. In addition they may adapt by changing their morphology, forming biofilms, fruiting bodies or spores, filaments, Viable But Not Culturable (VBNC) cells or moving away from stress compounds via chemotaxis. Changes in gene expression constitute the main component of the bacterial response to stress and environmental changes, and involve a myriad of different mechanisms, including (alternative) sigma factors, bi- or tri-component regulatory systems, small non-coding RNA’s, chaperones, CHRIS-Cas systems, DNA repair, toxin-antitoxin systems, the stringent response, efflux pumps, alarmones, and modulation of the cell envelope or membranes, to name a few. Many regulatory elements are conserved in different bacteria; however there are endless variations on the theme and novel elements of gene regulation in bacteria inhabiting particular environments are constantly being discovered. Especially in (pathogenic) bacteria colonizing the human body a plethora of bacterial responses to innate stresses such as pH, reactive nitrogen and oxygen species and antibiotic stress are being described. An attempt is made to not only cover model systems but give a broad overview of the stress-responsive regulatory systems in a variety of bacteria, including medically important bacteria, where elucidation of certain aspects of these systems could lead to treatment strategies of the pathogens. Many of the regulatory systems being uncovered are specific, but there is also considerable “cross-talk” between different circuits. Stress and Environmental Regulation of Gene Expression and Adaptation in Bacteria is a comprehensive two-volume work bringing together both review and original research articles on key topics in stress and environmental control of gene expression in bacteria. Volume One contains key overview chapters, as well as content on one/two/three component regulatory systems and stress responses, sigma factors and stress responses, small non-coding RNAs and stress responses, toxin-antitoxin systems and stress responses, stringent response to stress, responses to UV irradiation, SOS and double stranded systems repair systems and stress, adaptation to both oxidative and osmotic stress, and desiccation tolerance and drought stress. Volume Two covers heat shock responses, chaperonins and stress, cold shock responses, adaptation to acid stress, nitrosative stress, and envelope stress, as well as iron homeostasis, metal resistance, quorum sensing, chemotaxis and biofilm formation, and viable but not culturable (VBNC) cells. Covering the full breadth of current stress and environmental control of gene expression studies and expanding it towards future advances in the field, these two volumes are a one-stop reference for (non) medical molecular geneticists interested in gene regulation under stress.
