Research Publications (Food Safety)

Since 2010, reports of infection with hepatitis E virus (HEV) have increased in England and Wales. Despite mounting evidence regarding the zoonotic potential of porcine HEV, there are limited data on its prevalence in pigs in the United Kingdom. We investigated antibody prevalence, active infection, and virus variation in serum and cecal content samples from 629 pigs at slaughter.

Publication date: 1 October 2015
, Volume 210
Author(s): Seonyeong Choi , Sunhyung Park , Yoonsook Kim , Byeong-sam Kim , Larry R. Beuchat , Kim Hoikyung , Jee-Hoon Ryu

Hepatitis E virus (HEV) has emerged during the past decade as a causative agent of autochthonous hepatitis and is a clinical concern in Western developed countries. It has been increasingly recognized that pigs are a major reservoir of HEV of genotypes 3 and 4 worldwide and pig-derived food items represent a potential source of infections by these viruses in humans.

Aims
The aim of this study was to study inactivation of different pathogenic bacteria on agar model surface using TiO2-UV photocatalysis (TUVP).

Siderophores, small iron-binding molecules secreted by many microbial species, capture environmental iron for transport back into the cell. Vibrio cholerae synthesizes and uses the catechol siderophore vibriobactin and also uses siderophores secreted by other species, including enterobactin produced by Escherichia coli. E. coli secretes both canonical cyclic enterobactin and also linear enterobactin derivatives likely derived from its cleavage by the enterobactin esterase Fes.

In Salmonella enterica the thiamine biosynthetic intermediate 5-aminoimidazole ribonucleotide (AIR) can be synthesized de novo independent of the early purine biosynthetic reactions. This secondary route to AIR synthesis was dependent on i) amino-4-imidazolecarboxamide ribotide (AICAR) accumulation, ii) a functional phosphoribosylaminoimidazole-succinocarboxamide (SAICAR) synthetase (PurC, EC 6.3.2.6), and iii) methionine and lysine in the growth medium.

Salmonella enteric serovar Typhimurium (S. Typhimurium), a major cause of food-borne illness, is capable of using a variety of carbon and nitrogen sources. Fructoselysine and glucoselysine are Maillard reaction products formed by the reaction of glucose or fructose, respectively, with the -amine group of lysine. We report here that S.

Publication date: November 2015
, Volume 109
Author(s): Xuetong Fan , Kimberly J. Sokorai

Publication date: October 2015
, Volume 51
Author(s): Ana Graça , David Santo , Eduardo Esteves , Carla Nunes , Maribel Abadias , Célia Quintas

Aims
Using molecular subtyping techniques, Listeria monocytogenes is divided into three major phylogenetic lineages, and a multiplex PCR method can differentiate five L. monocytogenes subgroups: 1/2a-3a, 1/2c-3c, 1/2b-3b-7, 4b-4d-4e, and 4a-4c. In the current study, we conducted genome comparisons and evaluated serotype-associated genes for their utility as a multiplex PCR-based method for distinguishing high-risk serotypes 1/2a and 1/2c in lineage I from low-risk serotypes 3a and 3c.

Publication date: 1 October 2015
, Volume 210
Author(s): Jeanne-Marie Membré , Moctar Diao , Chantal Thorin , Grégoire Cordier , François Zuber , Stéphane André

Publication date: 1 October 2015
, Volume 210
Author(s): Dana Ziuzina , Lu Han , Patrick J. Cullen , Paula Bourke

Yersiniosis is strongly associated with the consumption of pork contaminated with enteropathogenic Yersinia enterocolitica, which is harbored by domestic pigs without showing clinical signs of disease. In contrast to data on Y. enterocolitica isolated from conventionally reared swine, investigations into the occurrence of Y. enterocolitica in wild boars in Germany are rare.

In this work, we examined the profile of metabolites produced from the doubly para-substituted biphenyl analogs 4,4'-dihydroxybiphenyl, 4-hydroxy-4'-chlorobiphenyl, 3-hydroxy-4,4'-dichlorobiphenyl, and 3,3'-dihydroxy-4,4'-chlorobiphenyl by biphenyl-induced Pandoraea pnomenusa B356 and by its biphenyl dioxygenase (BPDO).

Human norovirus (NoV) is the major causative agent of fresh-produce-related outbreaks of gastroenteritis; however, the ecology and persistence of human NoV in produce systems are poorly understood. In this study, the effects of abiotic and biotic stresses on the internalization and dissemination of two human NoV surrogates (murine norovirus 1 [MNV-1] and Tulane virus [TV]) in romaine lettuce were determined.

Food-borne pathogen persistence in soil fundamentally affects the production of safe vegetables and small fruits. Interventions that reduce pathogen survival in soil would have positive impacts on food safety by minimizing preharvest contamination entering the food chain. Laboratory-controlled studies determined the effects of soil pH, moisture content, and soil organic matter (SOM) on the survivability of this pathogen through the creation of single-parameter gradients.

Antimicrobial resistance in microbes poses a global and increasing threat to public health. The horizontal transfer of antimicrobial resistance genes was thought to be due largely to conjugative plasmids or transposons, with only a minor part being played by transduction through bacteriophages. However, whole-genome sequencing has recently shown that the latter mechanism could be highly important in the exchange of antimicrobial resistance genes between microorganisms and environments.

Human noroviruses (HNoV) and hepatitis A virus (HAV) have been implicated in outbreaks linked to the consumption of presliced ready-to-eat deli meats. The objectives of this research were to determine the thermal inactivation kinetics of HNoV surrogates (murine norovirus 1 [MNV-1] and feline calicivirus strain F9 [FCV-F9]) and HAV in turkey deli meat, compare first-order and Weibull models to describe the data, and calculate Arrhenius activation energy values for each model.

Bacteriophages UAB_Phi20, UAB_Phi78, and UAB_Phi87 were encapsulated in liposomes, and their efficacy in reducing Salmonella in poultry was then studied. The encapsulated phages had a mean diameter of 309 to 326 nm and a positive charge between +31.6 and +35.1 mV (pH 6.1). In simulated gastric fluid (pH 2.8), the titer of nonencapsulated phages decreased by 5.7 to 7.8 log units, whereas encapsulated phages were significantly more stable, with losses of 3.7 to 5.4 log units.

Infection by human pathogens through the consumption of fresh, minimally processed produce and solid plant-derived foods is a major concern of the U.S. and global food industries and of public health services. Enterohemorrhagic Escherichia coli O157:H7 is a frequent and potent foodborne pathogen that causes severe disease in humans. Biofilms formed by E. coli O157:H7 facilitate cross-contamination by sheltering pathogens and protecting them from cleaning and sanitation operations.

Human norovirus (NoV) is the leading cause of foodborne illness in the United States and Canada. Wastewater treatment plant (WWTP) effluents impacting bivalve mollusk-growing areas are potential sources of NoV contamination.

Campylobacter jejuni is a leading cause of human foodborne gastroenteritis worldwide. The interactions between this pathogen and the intestinal microbiome within a host are of interest as endogenous intestinal microbiota mediates a form of resistance to the pathogen. This resistance, termed colonization resistance, is the ability of commensal microbiota to prevent colonization by exogenous pathogens or opportunistic commensals. Although mice normally demonstrate colonization resistance to C.

Disposal of fecally contaminated poultry litter by land application can deliver pathogens and fecal indicator bacteria (FIB) into receiving waters via runoff. While water quality is regulated by FIB enumeration, FIB testing provides inadequate information about contamination source and health risk. This microbial source tracking (MST) study compared the persistence of the Brevibacterium sp.

Publication date: October 2015
, Volume 108
Author(s): M.K. Omer , B. Prieto , E. Rendueles , A. Alvarez-Ordoñez , K. Lunde , O. Alvseike , M. Prieto

Foodborne nickel content was determined in six strains of oat in a year-on-year analysisResults are depicted by relative standard deviation (RSD) values of 17.94 and 31.41%. Wider range of differential is featured in processed foods, with RSD spanning 10–65%. While most studies are confined to analyses in output data only, in this article we dissect the mechanisms that underlie nickel migration in the progress of industrial processing.