Research Publications (Food Safety)

Pathogenic properties of orthologues to S. aureus staphylococcal enterotoxin C (SEC) and staphylococcal enterotoxin L (SEL) produced by S. epidermidis are largely unexplored. We assessed the enteropathogenic effects of S. epidermidis SECepi and SELepi and S. aureus SEC3 and SEL after oral administration to Balb/c mice. Intestinal sections from SE-treated mice were analyzed histopathologically.

Recently, frequent outbreaks of foodborne diseases have attracted increasing attention, and how to rapidly detect foodborne pathogens has also become an urgent issue. Herein, we reported the colorimetric sensor based on chitosan-coated magnetic nanoparticles (CS@MNPs) for rapidly broad-spectrum detection of the total bacterial count, whose color change can be visible to the naked eye without any other sophisticated instruments.

Yersinia (Y.) enterocolitica, an etiological agent of yersiniosis, is a bacterium whose pathogenicity is determined, among other things, by its ability to produce toxins. The aim of this article was to present the most important toxins that are produced by biotype 1A strains of Y. enterocolitica, and to discuss their role in the pathogenesis of yersiniosis. Y.

Viable foodborne pathogens can cause intestinal infection and food poisoning. Herein, we reported an RNA assay allowing for sensitive (close to 1 CFU and 1% viable bacteria detectable) and rapid (within 2.5 h) detection of viable pathogenic bacteria by coupling isothermal RNA amplification (nucleic acid sequence-based amplification, NASBA) with a CRISPR/Cas13a system. NASBA allowed direct amplification of 16S rRNA extracted from viable S.

Fresh produce remains the leading cause of foodborne illness outbreaks. Novel nonthermal technologies are needed to reduce the risk of pathogen contamination. The objective of this study was to develop a novel intervention technology exploiting integration of high intensity short time (10 s) pulsed light (PL) and aerosolized formic acid (AFA) for inactivation of Salmonella and maintenance of quality of cherry tomato.

As global warming increases the geographical range and frequency of Vibrio parahaemolyticus infections, its formation of biofilms providing bacteria greater resistance to stress and contributing to the persistence of pathogens, is threatening the seafood industry. V. parahaemolyticus has a number of advantages leading to biofilm formation.

Background The Clear Safety Salmonella method was modified to improve sample preparation, PCR reagents, library preparation, flow cell quality control, library loading mix, priming mix, and sequencing kit reagents and steps. Objective To evaluate the modified Clear Safety Salmonella method (manual and automated) via independent and method developer validation studies according to current AOAC INTERNATIONAL Validation Guidelines.

Background The Clear Safety Listeria method utilizes polymerase chain reaction (PCR) amplification and targeted next-generation sequencing technology to detect Listeria species (L. monocytogenes, L. innocua, L. ivanovii, L. marthii, L. grayi, L. welshimeri, and L. seeligeri) in hot dogs and on selected environmental surfaces. Objective The aim was to validate the candidate method according to current AOAC guidelines.

Background The candidate method, SMARTCHEK Salmonella spp. Detection Kit assay is designed for rapid detection of Salmonella spp. in select food matrixes, for use in conjunction with the Genesystems Rapi:chipTM and GENECHECKER UF-300 real-time PCR system. Objective The independent laboratory evaluation consisted of an inclusivity and exclusivity study, product consistency study, robustness study, stability study, and a matrix study.

Background The Thermo Scientific™ SureTect™ Salmonella species PCR Assay utilizes Solaris™ reagents for performing PCR for the rapid and specific detection of Salmonella species in a broad range of foods and select environmental surfaces. Objective The aims were to demonstrate the reproducibility of the Thermo Scientific SureTect Salmonella species PCR Assay in a collaborative study using a challenging matrix, cocoa powder, and to extend the scope of the method.

During the spring of 2018, the U.S. Food and Drug Administration (FDA), U.S. Centers for Disease Control and Prevention (CDC), states and local public health agencies responded to a multistate outbreak of gastrointestinal illnesses caused by multiple   Salmonella   serovars and associated with consumption of kratom, a product harvested from a tropical tree native to Southeast Asia. The outbreak included 199 case-patients reported by 41 U.S.

Bacillus cereus spores have the ability to adhere to solid surfaces, including stainless steel, a material widely used in food industries. Adhesion of spores allows for recontamination during food processing, and the cleaning and disinfection are largely used by industries to control them.

Hong Kong oyster (Crassostrea hongkongensis) is one of the main species of economic shellfish cultivated in the coastal areas of southern China. The cultivation of this shellfish may be adversely impacted by Vibrio parahaemolyticus, a harmful pathogenic bacterium for many mariculture species, as it usually exists on the surface of Hong Kong oysters.

The survivability and thermal resistance of L. monocytogenes was determined in dry and hydrated nonfat dry milk (NFDM) and whole milk powder (WMP) during 180 days of storage. The hydrated milks were prepared from stored, inoculated milk powders on the day of D- and z-value analyses. The overall L. monocytogenes population in milk powders was 7.0 log cfu g-1 on day 1, which reduced by ∼2.2 log cfu g-1 at the end of storage.

Salmonella is the leading cause of zoonotic foodborne illnesses worldwide and a prevalent threat to the poultry industry. For controlling contamination, the use of chemical sanitizers in combination with biological compounds (e.g., enzymes) offers a solution to reduce the chemical residues.

Human listeriosis outbreaks are often associated with food products, which could be contaminated, at the same time, also by different clones of Listeria monocytogenes. This emphasize the need to type more than one L. monocytogenes isolate found in a single food or environmental sample. The purpose of the present study was to evaluate the presence of different L. monocytogenes strains in food and food production environment in order

This study aimed to determine the growth potential (δ) of L. monocytogenes (CLIST 3974, CLIST 3969, and CLIST 4162) and S. enterica [S. Typhimurium (ATCC SM 14028), S. Enteritidis (SM 64), and S. Montevideo (SM 129)] in the presence of a pool of lactic acid bacteria (LAB) with antimicrobial activity in Frescal and semi-hard Minas microcheeses.

Vibrio cholerae O1 and O139 isolates deploy cholera toxin (CT) and toxin-coregulated pilus (TCP) to cause the diarrhoeal disease cholera.

Chlorine disinfectants have been widely used in the poultry supply chain but this exposure can also result in the development of bacterial tolerance to chlorine and this is often linked to antibiotic cross-resistance. The objectives of this study were to investigate sodium hypochlorite (NaClO) tolerance of Salmonella isolated from poultry supply chains and evaluate cross-resistance.

Shigella flexneri is a waterborne and foodborne pathogen that can damage human health. The exopolysaccharides (S-EPS) produced by S. flexneri CMCC51574 were found to promote biofilm formation and virulence. In this research, the crude S-EPS produced by S. flexneri CMCC51574 were separated into three main different fractions, S-EPS 1-1, S-EPS 2-1, and S-EPS 3-1. The structure of the S-ESP 2-1 was identified by FT-IR, ion chromatography analysis, methylation analysis, and NMR analysis.

Salmonella spp. causes foodborne diseases related to the consumption of contaminated foods, especially poultry products. This study aimed to investigate the occurrence of Salmonella spp. serovars in raw eggs from supermarkets and street food markets in southern Brazil, to analyze virulence genes, resistance profiling to antimicrobials and sanitizers, and to determine the susceptibility of the isolates to Butia odorata extract.

This study evaluated high pressure processing (HPP) for achieving greater than 5-log reduction of Escherichia coli O157:H7 in shiikuwasha (Citrus depressa Hayata) juices and compare quality parameters, including microbiological safety, total phenolic content (TPC), total flavanones (TFC), and polymethoxylated flavones, browning, volatile aromatic, and physicochemical properties of HPP-treated juice with those of high-temperature short-time pasteurized juice.

During infection, bacteria use an arsenal of resistance mechanisms to negate antibiotic therapies. In addition, pathogenic bacteria form surface-attached biofilms bearing enriched populations of metabolically dormant persister cells. Bacteria develop resistance in response to antibiotic insults; however, nonreplicating biofilms are innately tolerant to all classes of antibiotics. As such, molecules that can eradicate antibiotic-resistant and antibiotic-tolerant bacteria are of importance.

Salmonella remains one of the most common foodborne pathogens worldwide, and its resistance to antimicrobials has increased considerably over the years. In this context, was evaluated the action of three bacteriophages isolated or combined in inhibiting the adhesion and removal of Salmonella Heidelberg biofilm on a polystyrene surface.

Intestinal pathogens must combat host and microbiota-associated resistance to establish an infection. A new study (Shelton et al.) highlights how Salmonella manipulates the mammalian host to produce anaerobic respiratory electron acceptors, allowing catabolism of propionate and providing a competitive edge to Salmonella residing in the gut.