Research Publications (Food Safety)

The Pacific Northwest (PNW) is one of the largest commercial harvesting areas for Pacific oysters (Crassostrea gigas) in the United States. Vibrio parahaemolyticus, a bacterium naturally present in estuarine waters accumulates in shellfish and is a major cause of seafood-borne illness. Growers, consumers, and public-health officials have raised concerns about rising vibriosis cases in the region.

Chitosan-ZnO nanoparticle (ZnONP) edible coating was applied to extend shelf life of wild-simulated Korean ginseng root (WsKG). In antimicrobial testing of various coating solutions (0.01, 0.02, 0.03% ZnONP), Bacillus cereus (Gram-positive) and Escherichia coli (Gram-negative) were most inhibited by the 0.03% chitosan-ZnONP solution. The 0.03% chitosan-ZnONP solution was finally used for edible coating of WsKG.

This study aims to test the toxicity of some metallic elements on Salmonella enterica strains and their power to grow and to develop a biofilm to overcome this environmental stress. From 50 selected strains of Salmonella, 70% belong to the Kentucky serotypes that is the most frequent one, followed by the other serotypes such as Amsterdam 6%, anatum 4%, derby 4% Enteritidis 4%, Zanzibar 4%, typhyrimium 2%, gallinaruim 2%, inbondaka 2% and Newport 2%.

The most commonly reported serotype of Shiga toxin-producing Escherichia coli (STEC) is O157:H7. This pathogen presents a threat to public health and is a cause of foodborne illness worldwide. The efficient and sensitive detection of E. coli O157:H7 remains a challenge for food safety. In this report, we developed a sensitive and specific loop-mediated isothermal amplification (LAMP) reaction coupled with a lateral flow (LF) assay to rapidly detect E. coli O157:H7.

Methicillin-resistant Staphylococcus aureus (MRSA) regulates resistance to β-lactams via preferential production of an alternative penicillin-binding protein (PBP), PBP2a. PBP2a binds many β-lactam antibiotics with less affinity than PBPs which are predominant in methicillin-susceptible (MSSA) strains. A novel, rather frequent in vitro phenotype was recently identified among clinical MRSA bloodstream isolates, termed “NaHCO3-responsiveness”.

The safety risks of antimicrobial peptide (AMP) resistance have never been properly understood. Herein, we comprehensively investigated the evolution of resistance to AMPs in Staphylococcus aureus using piscidin1 (PIS-1) and piscidin3 (PIS-3) as archetypes, in which they were both combined with cell membranes via a common structural motif but vary in permeabilizing actions.

The stringent response mediated by the signal molecule (p)ppGpp is involved in response to multiple environmental stresses and control of various physiological processes. Studies have revealed that (p)ppGpp strongly affects the formation and maintenance of several bacterial biofilms. However, the specific regulatory roles of (p)ppGpp in biofilms, especially in the expression of genes related to cell motility and exopolysaccharides (EPSs) production, remain poorly understood.

Cholera continues to be a major burden for developing nations, especially where sanitation, quality of water supply, and hospitalization have remained an issue. Recently, growing antimicrobial-resistant strains of Vibrio cholerae underscores alternative therapeutic strategies for cholera. Bacteriophage therapy is considered one of the best alternatives for antibiotic treatment.

The effects of hydrogen sulfide (H2S) on diabetic metabolic disorders are still controversial, and the mechanisms underlying these effects remain largely unknown. This study was conducted to investigate the potential relationship between the gut microbiota and the improvement of diabetic metabolic disorders by exogenous H2S in obese db/db mice. The db/db mice were treated with sodium hydrosulfide (NaHS) (80 μmol/kg), or vehicle for 16 weeks, respectively.

Zoonoses and Public Health, EarlyView. Yersinia enterocolitica is a human pathogen transmitted via the faecal–oral route among animals and humans and is a major foodborne public health hazard. This study explores the role of Y. enterocolitica transmission at the livestock–wildlife interface and investigates the potential role wild and peridomestic rodents play as a source of this zoonotic pathogen.

Even though Listeria monocytogenes is an extensive-studied foodborne pathogen, genome analysis of isolates from snails that may represent a reservoir of L. monocytogenes are still scarce. Here, we use whole-genome sequencing (WGS) to assess the genomic diversity of hypervirulent, virulent and non-virulent phenotypes of 15 L.

Background Cereulide, a potent toxin produced by emetic Bacillus cereus (B. cereus), is a small, heat- and acid-stable cyclic dodecadepsipeptide known as a potassium-selective ionophore. Recently, cereulide is responsible for an increasing number of foodborne poisonings due to changes in lifestyle and eating habits.

Bacterial drug resistance caused by overuse and misuse of antibiotics is common, especially in clinical multispecies infections. It is of great significance to discover novel agents to treat clinical bacterial infections. Studies have demonstrated that autoinducer-2 (AI-2), a signal molecule in quorum sensing (QS), plays an important role in communication among multiple bacterial species and bacterial drug-resistance.

Salmonella enterica serovar Infantis is one of the five main causes of human salmonellosis in the European Union (EU) and in recent years, has been increasingly reported to carry multiple antimicrobial resistance determinants, including extended-spectrum beta-lactamase (ESBL) genes. In our study, we used WGS-based tools to characterize S. Infantis strains circulating in the Abruzzo and Molise regions of Italy between 2017 and 2020 and compared this local dataset to the S.

Bacillus cereus is widely distributed in foods, especially dairy products, and can lead to diarrhea (non-emetic B. cereus) and emesis (emetic B. cereus). Although diarrhea due to B. cereus is usually mild, emesis can lead to acute encephalopathy and even death. To develop rapid and sensitive detection methods for B. cereus in foods, specific primers targeting the gyrase B (gyrB) and cereulide synthetase (ces) genes were designed and screened using recombinase polymerase amplification (RPA).

Daptomycin is an important antibiotic used for treating serious infections caused by Gram-positive bacteria including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci. Establishing structure–activity relationships of daptomycin is important for developing new daptomycin-based antibiotics with expanded clinical applications and for tackling the ever-increasing problem of antimicrobial resistance.

Salmonellosis is a prevalent food poisoning disease caused by Salmonella spp. that affects millions of people throughout the world. Contamination of chicken meat and processing equipment with Salmonella is a major issue in the food industry.

The potential of organic acids to inactivate foodborne pathogens in food industry has gained attention, while the sanitizing mechanism of acid stress has not been explained fully at metabolomics level.

Abstract Staphylococcus aureus is a major human pathogen, and the appearance of methicillin-resistant S. aureus (MRSA) renders S. aureus infections more challenging to treat. Therefore, new antimicrobial drugs are urgently needed to combat MRSA infections. Drug repurposing is an effective and feasible strategy.

by Hamza Hamad Matimba, Agricola Joachim, Mucho Michael Mizinduko, Irene Anthony Maseke, Salum Kassim Nyanga, Maria Ezekiely Kelly, Ali Said Nyanga, Janneth Maridadi Mghamba, Mtebe Venance Majigo, Ahmed Abade Mohamed Background Cholera continues to cause morbidity and mortality in developing countries, including Tanzania. Since August 2015, Tanzania Mainland has experienced cholera outbreaks affecting 26 regions and a 1.6% case fatality rate.

Cross-contamination of Listeria monocytogenes from raw to ready-to-eat (RTE) foods has caused a number of foodborne outbreaks. This study used the quantitative exposure assessment to analyze the transfer risk of L.

Salmonella enterica subspecies enterica serovar Typhimurium (S. Typhimurium) definitive phage type 104 (DT104), S.

The antimicrobial activity of several essential oils (EOs) and their related microemulsions (MEs) was investigated. EOs were obtained from Cannabis sativa L. cv CS (C. sativa), Carum carvi L. (C. carvi), Crithmum maritimum L. (C. maritimum), Cuminum cyminum L. (C. cyminum), x Cupressocyparis leylandii A.B. Jacks & Dallim. (C. leylandii), Cupressus arizonica Greene (C. arizonica), Ferula assa-foetida L. (F. assa-foetida)., Ferula gummosa Boiss. (F.

Gram-positive bacteria do not produce lipopolysaccharide as a cell wall component. As such, the polymyxin class of antibiotics, which exert bactericidal activity against Gram-negative pathogens, are ineffective against Gram-positive bacteria. The safe-for-human-use hydroxyquinoline analog ionophore PBT2 has been previously shown to break polymyxin resistance in Gram-negative bacteria, independent of the lipopolysaccharide modification pathways that confer polymyxin resistance.

Molecular Microbiology, Accepted Article. The behaviours of infectious bacteria are commonly studied in bulk. This is effective to define general properties of a given isolate, but insufficient to resolve subpopulations and unique single-microbe behaviours within the bacterial pool.