Research Publications (Food Safety)

We investigated whether the co-occurrence of phytopathogens ( Clavibacter michiganensis  subsp.  michiganensis [ Cmm ] and  Xanthomonas gardneri  [ Xg ]) frequently encountered in tomato production and  Salmonella   enterica  subsp.  enterica  serotype Typhimurium (JSG626) affects the persistence of these pathogens in tomato plant tissues during the early stages of plant growth .

Salmonella is one of the main causes of foodborne infectious diseases, posing a serious threat to public health. It can enter the food supply chain at various stages of production, processing, distribution, and marketing. High prevalence of Salmonella necessitates efficient and effective approaches for its identification, detection, and monitoring at an early stage.

While the increase in thermal resistance of microorganisms at reduced water activity is demonstrated for low-moisture food products, the effect of storage time on the thermal resistance of microorganisms in low-moisture foods is not well established. As low-moisture foods are stored for long periods and are used as ingredients, cross-contamination can occur at any time period before the lethality step.

Author(s): Eloísa Sevilla, Juan P. Vico, José F. Delgado-Blas, Bruno González-Zorn, Clara Mª. Marín, Cristina Uruén, Inmaculada Martín-Burriel, Rosa Bolea, Raúl C. Mainar-Jaime

Microorganisms play a crucial and unique role in fish and fish product safety. The presence of human pathogens and the formation of histamine caused by spoilage bacteria make the control of both pathogenic and spoilage microorganisms critical for fish product safety.

This study aimed to investigate the inactivation effect of 150 KeV low-energy X-ray on Salmonella Typhimurium, Escherichia coli O157:H7, Staphylococcus aureus, and Listeria monocytogenes that were inoculated in dry cardamom. The D10 value for E. coli O157:H7 was 71.43 Gy and the tR values for S. Typhimurium, L. monocytogenes, and S. aureus were 53.57, 87.74, and 114.64 Gy, respectively.

Multidrug-resistant Salmonella enterica subspecies enterica 4,[5],12:i:- sequence type 34 represents a worldwide public health risk. To determine its origin in the United States, we reconstructed a time-scaled phylogeny with a discrete trait geospatial model. The clone in the United States was introduced from Europe on multiple occasions in the early 2000s.

Author(s): J.M. Choi, E. Camfield, A. Bowman, K. Rajan, N. Labbé, K.D. Gwinn, B.H. Ownley, N. Moustaid-Moussa, D.H. D'Souza

Salmonellosis is one of the most important bacterial diseases in pigeons. This study aimed to estimate the prevalence of Salmonella spp. in domestic pigeons (Columba livia f. domestica) in Poland, its antimicrobial susceptibility (both phenotypic and genotypic), and its capability for biofilm formation. The presence of selected virulence genes, nucleotide homology of selected genes, and susceptibility to bacteriophages were investigated as well.

There has been an increase in the number of reports on Salmonella enterica subsp. enterica serovar Infantis (S. Infantis) isolated from animals and humans. Recent studies using whole genome sequencing (WGS) have provided evidence on the likely contribution of a unique conjugative megaplasmid (pESI; ~280 kb) to the dissemination of this serovar worldwide. In the present study, twenty-two unrelated Salmonella strains [S.

Following two O121 STEC outbreaks linked to wheat flour, this study was conducted to gain baseline information on the occurrence of bacterial pathogens and levels of indicator organisms in wheat flour in Canada. A total of 347 pre-packaged wheat flour samples were analyzed for Salmonella spp., Shiga Toxin-Producing Escherichia coli (STEC), Listeria monocytogenes ( L. monocytogenes ) , aerobic colony count (ACC), total coliforms, and generic Escherichia coli ( E. coli ) .

Different methods for determining the thermal inactivation kinetics of microorganisms could result in discrepancies of the resulting thermal resistance values. This study determined the thermal resistance of Salmonella in whole milk powder using three methods (Thermal death time (TDT) disk in water bath, pouches in water bath, and TDT Sandwich).

ABSTRACT While high temperature heat treatments can efficiently reduce pathogen levels, they also affect the quality and nutritional profile of foods, as well as increase the cost of processing. The food additive butyl para-hydroxybenzoate (BPB) was investigated for its potential to synergistically enhance the thermal inactivation at mild heating temperatures (54 – 58 ºC).

This study focuses on foodborne outbreaks of microbial infection associated with fresh produce in Europe and North America from this millennium. A total of 277 outbreaks with 44,524 individual cases were identified. Foodborne pathogens associated with the most outbreak frequency include Cryptosporidium (20.5%) in Europe and Salmonella (52.2%) in North America although Norovirus (54.3%) and Salmonella (61.3%) were associated with the number of cases in Europe and North America respectively.

Aim Gonorrhoea remains a leading public health burden and the development of vaccine against gonorrhoea becomes more urgent. Here, a novel Neisseria gonorrhoeae DNA vaccine delivered by Salmonella enteritidis ghosts was developed and the immune responses of the vaccine candidate were evaluated. Methods and Results Neisseria gonorrhoeae nspA gene was cloned into the pVAX1 vector.

Author(s): Amninder Singh Sekhon, Arshdeep Singh, Phoebe Unger, Monipel Babb, Yaeseol Yang, Minto Michael

Several genes of the eut, pdu, and cob/cbi operons are responsible for the metabolism of ethanolamine (EA) and 1,2-propanediol (PD) and are essential during the pathogenic lifecycles of various enteric pathogens. Studies concerning EA and PD metabolism have primarily focused on bacterial genera from the family Enterobacteriaceae, especially the genus Salmonella.

Author(s): Tareq M. Osaili, Fayeza Hasan, Dinesh Kumar Dhanasekaran, Reyad S. Obaid, Anas A. Al-Nabulsi, Mutamed Ayyash, Layal Karam, Ioannis N. Savvaidis, Richard Holley

Aims This study compared the capacity of strains of Salmonella enterica serovars Enteritidis and Dublin isolated in Brazil to invade epithelial cells, to be internalized by and survive within macrophages, and to stimulate cytokine release in vitro. Methods and Results Both serovars infected 75% and 73% Caco‐2 (human) and MDBK (bovine) epithelial cells, respectively. S. Dublin and S.

Background Typhoid fever caused by Salmonella Typhi is a major public health concern in low-/middle-income countries. A recent study of 1900 global S. Typhi indicated that South Asia might be the site of the original emergence of the most successful and hypervirulent clone belonging to the 4.3.1 genotype. However, this study had limited samples from India. Methods We analyzed 194 clinical S.

Salmonella enterica is one of the most common bacterial foodborne pathogens in the United States, causing illnesses that range from self-limiting gastroenteritis to more severe, life threatening invasive disease. Many Salmonella strains contain plasmids that carry virulence, antimicrobial resistance, and/or transfer genes which allow them to adapt to diverse environments, and these can include incompatibility group (Inc) FIB plasmids.

Colibacillosis is an economically important infectious disease in poultry, caused by avian pathogenic Escherichia coli (APEC). Salmonella enterica serovar Enteritidis (S. Enteritidis) is a major cause of food-borne diseases in human circulated through poultry-derived products, including meat and chicken eggs.

Author(s): Barun Yadav, M.S. Roopesh

Diseases caused by Escherichia coli (E. coli) and Salmonella spp. can negatively impact turkey farming. The aim of this study was to isolate and characterize multidrug-resistant (MDR) E. coli and Salmonella spp. in healthy and diseased turkeys. A total of 30 fecal samples from healthy turkeys and 25 intestinal samples from diseased turkeys that died of enteritis were collected. Bacterial isolation and identification were based on biochemical properties and polymerase chain reaction (PCR).

Salmonella Typhimurium expresses on its outer membrane the protein Rck which interacts with the epidermal growth factor receptor (EGFR) of the plasma membrane of the targeted host cells. This interaction activates signaling pathways, leading to the internalization of Salmonella. Since EGFR plays a key role in cell proliferation, we sought to determine the influence of Rck mediated infection on the host cell cycle.