Research Publications (Food Safety)

Salmonella is a zoonotic foodborne bacterial pathogen that can seriously harm health. Persistence of Salmonella and antibiotic resistance genes (ARGs) in different types of soil under flooding and natural conditions are rare explored. This study investigated the dynamic changes of the Salmonella, ARGs and bacterial communities in three types of soils applied with pig manure in lab scale.

Egg white powder (EWP), the main ingredient in many food products, is widely used in the food industry due to its whipping, textural properties and practical advantages. Significant food safety risks might occur when contamination/cross-contamination takes place after a lethal processing step. It is critical to use appropriate D- and Z-values to evaluate the food safety risks.

Salmonella enterica is a diverse species of bacterial pathogens comprised of >2,500 serovars with variable host ranges and virulence properties. Accumulating evidence indicates that two AB5-type toxins, typhoid toxin and ArtAB toxin, contribute to the more severe virulence properties of the Salmonella strains that encode them.

Background Food-borne infections mainly due to Salmonella enterica serovar Enteritidis (S. Enteritidis) are major concerns worldwide. S. Enteritidis isolates may serve as reservoirs for spreading antimicrobial drug resistance genes including carbapenemases. This study aimed to screen the occurrence of virulence factors, carbapenemases, and antibiotic resistance genes in S.

With mounting evidence indicating an enhanced thermal resistance of Salmonella at lower aw, the effectiveness of thermal treatment in wheat flour decontamination is challenged.

Fresh food products can be contaminated with pathogenic bacteria in various agricultural environments. Potting soil is sterilized by heat sterilization and then reused. This study evaluated the effects of three sterilization methods (non-sterilized, pasteurized, and sterilized) on the survival of pathogenic bacteria in potting soil during storage for 60 days at 5, 15, 25, and 35 °C.

The occurrence of waterborne antimicrobial-resistant (AMR) bacteria in areas of high-density oyster cultivation is an ongoing environmental and public health threat given the popularity of shellfish consumption, water-related human recreation throughout coastal Thailand, and the geographical expansion of Thailand’s shellfish industry.

by Felipe Pinheiro Vilela, Dália dos Prazeres Rodrigues, Marc William Allard, Juliana Pfrimer Falcão Salmonella enterica subspecies enterica serovar Infantis (S. Infantis) is a non-typhoid, zoonotic and foodborne serovar with worldwide distribution, and often associated with increasing antimicrobial resistance. Efflux pumps are antimicrobial resistance mechanisms able to promote and increase resistance levels to multiple distinct drug classes.

The physiological status of Salmonella after its ultrasonication was investigated to reveal the potential mechanism through which ultrasound enhances the lethality of chlorine dioxide against Salmonella.

Many niche-dependent barriers along the poultry production continuum favour the survival of certain Salmonella serovars over others. Historically, the presence of particular serovars has been determined by niche-specific genes which encode resistance to selective pressures such as host defenses and industrial antimicrobial practices. Over the past decade, Canada has witnessed unexplained shifts in the Salmonella landscape in the poultry sector.

mBio, Ahead of Print. Bacterial populations can survive exposure to antibiotics through transient phenotypic and gene expression changes. These changes can be attributed to a small subpopulation of bacteria, giving rise to antibiotic persistence. Although this phenomenon has been known for decades, much remains to be learned about the mechanisms that drive persister formation. The RNA-binding protein ProQ has recently emerged as a global regulator of gene expression.

Bacillus subtilis (BS) has been used as an excellent probiotic; however, some BS strains seem to be opportunist pathogens or do not present inhibitory effects in the pathogenic bacteria, so the characterization of BS strains for use in animals is mandatory. This study aimed to select nonpathogenic strains of BS, which can inhibit Salmonella spp., avian pathogenic Escherichia coli (APEC), and Campylobacter jejuni (CJ) using a chicken embryo as a model.

Rapid detection of target foodborne pathogens plays more and more significant roles in food safety, which requires the efficiency, sensitivity, and accuracy. In this research, we proposed a new strategy of isothermal-molecular-amplification integrated with lateral-flow-strip for rapid detection of Salmonella without traditional enrichment-culture.

Cross protection can undermine the effectiveness of control measures on foodborne pathogens, and therefore brings major implications for food safety. In this work, the capacity of Salmonella Enteritidis to mount ethanol tolerance following acid adaptation was characterized by analysis of cell viability and cell membrane property.

Mercury (Hg) pollution poses human health and environmental risks worldwide, as it can have toxic effects and causes selective pressure that facilitates the spread of antibiotic resistant genes (ARGs) among microbes. More and more studies have revealed that numerous Hg-related genes (HRGs) can help to resist and transform Hg.

The emergence and rapid spread of multidrug resistant (MDR) Gram-negative bacteria have posed a serious threat to global health and security. Because of the time-consuming, high cost and high risk of developing new antibiotics, a significant method is to use antibiotic adjuvants to revitalize the existing antibiotics.

Rapid and efficient detection of foodborne pathogens is an important means of disease prevention. In this study, a low field NMR (Nuclear magnetic resonance) biosensor based on high density carboxyl polyacrylate targeting Gadolinium (Gd) probe was developed for rapid detection of Salmonella in milk. First, with activated polyacrylic acid and the streptavidinylated polyacrylic acid (SA-PAA) was obtained through amide reaction.

Salmonella is a major pathogen that causes serious foodborne diseases in humans and poses a serious threat to food safety and public health worldwide. Its rapid and accurate diagnosis is essential to prevent bacterial contamination of food.

Journal of Bacteriology, Ahead of Print. Pathogens are becoming resistant to antimicrobials at an increasing rate, and novel therapeutic strategies are needed. Using Salmonella as a model, we have investigated the induction of sugar-phosphate toxicity as a potential therapeutic modality. The approach entails providing a nutrient while blocking the catabolism of that nutrient, resulting in the accumulation of a toxic intermediate.

Journal of Bacteriology, Ahead of Print. The global rise of drug-resistant bacteria is of great concern. Conjugative transfer of antibiotic resistance plasmids contributes to the emerging resistance crisis. Despite substantial progress in understanding the molecular basis of conjugation in vitro, the in vivo dynamics of intra- and interspecies conjugative plasmid transfer are much less understood.

The Ag/AgCl composite can be synthesized using various chemical, physical, and biological methods. Biosynthesis of nanoparticles is a rapid technology and has advantages over physical and chemical synthesis methods. This research is based on the bacterial formation of silver nanoparticles by bacterial strain Tmas-01. The bacterial strain Tmas-01 was isolated from soil samples and screened for its potential to form Ag/AgCl composite.

Salmonella enteritidis (SE) accounts for more than 70% of Salmonella spp. infections in humans with a primary source being chicken eggs, that can result from post-lay SE cross-contamination of the shell from contaminated equipment or the environment.

Despite their clonality, intracellular bacterial pathogens commonly show remarkable physiological heterogeneity during infection of host cells. Physiological heterogeneity results in distinct ultrastructural morphotypes, but the correlation between bacterial physiological state and ultrastructural appearance remains to be established. In this study, we showed that individual cells of Salmonella enterica serovar Typhimurium are heterogeneous in their ultrastructure.

Salmonella is one of the most common foodborne pathogens that cause diarrhea in human, in which Enteritidis and Typhimurium are the top serovars frequently isolated from foodstuffs. A novel 3-plex droplet digital PCR (ddPCR) was successfully developed in this study for the simultaneous identification and absolute quantification of Salmonella and its two important serovars (Enteritidis and Typhimurium).

The National Antimicrobial Resistance Monitoring System (NARMS) is a One Health program in the United States that collects data on antimicrobial resistance in enteric bacteria from humans, animals, and the environment. Salmonella is a major pathogen tracked by the NARMS retail meat arm but currently lacks a uniform screening method.