Research Publications (Food Safety)

Dates are a low moisture ready‐to‐eat fruit which are popular both globally and in the United States. The harvesting and post‐harvest handling of dates could result in the contamination of common produce‐associated foodborne pathogens including E. coli O157:H7, Listeria monocytogenes, and Salmonella spp. In this study, the efficacy of antimicrobial washes for the reduction of foodborne pathogen populations was evaluated as a post‐harvest mitigation step.

During passage through the human gastrointestinal tract, enterohemorrhagic Escherichia coli (EHEC) is exposed to membrane-damaging bile in the small intestine. We previously reported that EHEC treatment with a physiological bile salt mixture upregulates basRS, encoding a two-component system, and arnBCADTEF, encoding the aminoarabinose lipid A modification pathway (J. V. Kus, A. Gebremedhin, V. Dang, S. L. Tran, A. Serbanescu, and D.

Wine and alcoholic apple cider are commonly back-sweetened with unpasteurized juice to produce fresh, natural, and palatable sweetened alcoholic beverages. Foodborne pathogens may be introduced from unpasteurized juice into alcoholic beverages through this back-sweetening process. Although pathogens generally do not survive under low pH conditions or high alcohol environment, the die-off of these pathogens has not been established to ensure the safety of the products.

Due to the relatively high tolerance and resistance to sanitizers, biofilms can persist in the environment resulting in cross-contamination. The overall goal of this study was to evaluate the impact of nanobubbles (NB) alone and in combination with neutral electrolyzed water (NEW) on different microbial biofilms including Escherichia coli O157:H7, Vibrio parahaemolyticus, and Listeria innocua on plastic and stainless steel (SS) coupons.

In this study, a real-time loop-mediated isothermal amplification (Rti-LAMP) combined with immunomagnetic beads separation (IMS) and ethidium bromide monoazide (EMA) treatment was developed for the rapid and ultrasensitive detection of viable Escherichia coli (E. coli) O157:H7 in milk without enrichment. Polyclonal antibodies against E. coli O157:H7 flagellum and specific immunomagnetic beads (IMBs) were prepared.

ABSTRACT

Subcutaneous vaccination of cattle for enterohemorrhagic Escherichia coli O157:H7 reduces the magnitude and duration of fecal shedding, but the often-required, repeated cattle restraint can increase costs, deterring adoption by producers. In contrast, live oral vaccines may be repeatedly administered in feed, without animal restraint. We investigated whether oral immunization with live stx-negative LEE+ E. coli O157:H7 reduced rectoanal junction (RAJ) colonization by wild-type (WT) E.

Once pathogens are internalized in fresh produce, they pose a challenging food safety issue since they are not effectively inactivated by conventional rinsing or sanitization.

This study evaluated the effects of Bacillus amyloliquefaciens (B. amyloliquefaciens) TL106 isolated from Tibetan pigs’ feces, on the growth performance, immune response, intestinal barrier function, morphology of jejunum, cecum and colon, and gut microbiota in the mice with enterohemorrhagic Escherichia coli (EHEC)‐induced intestinal diseases.

Acid treatment is commonly used for controlling or killing pathogenic microorganisms on medical devices and environments; however, inadequate acid treatment may cause acid tolerance response (ATR) and offer cross-protection against environmental stresses, including antimicrobials. This study aimed to characterise an Escherichia coli strain that can survive in the acidic gastrointestinal environment.

Enterohemorrhagic Escherichia coli (EHEC) strains, including E. coli O157:H7, cause severe illness in humans due to the production of Shiga toxin (Stx) and other virulence factors. Because Stx is coregulated with lambdoid prophage induction, its expression is especially susceptible to environmental cues. Infections with Stx-producing E. coli can be difficult to model due to the wide range of disease outcomes: some infections are relatively mild, while others have serious complications.

The incidence of foodborne diseases has continuingly increased over the years and resulted in public health problem globally. Enterohemorrhagic Escherichia coli O157:H7 (E. coli O157:H7) is a human pathogen that causes diarrhea and hemorrhagic colitis. E. coli O157:H7 can be found in various foods. It is important to detect this foodborne pathogen to provide safe food supply.

Background
Manure application and sewage irrigation release many intestinal pathogens into the soil. After being introduced into the soil matrix, pathogens are commonly found to attach to soil minerals. Although the survival of mineral-associated Escherichia coli O157:H7 has been studied, a comprehensive understanding of the attachment process and physiological properties after attachment is still lacking.

Pathogenic bacterial contamination is a serious problem for the food industry and in public health. Rapid, accurate and affordable testing for pathogenic bacterial strains is desirable. In this study, a competition visual antigen macroarray (CVAM) for rapid detection of Escherichia coli O157:H7 (E. coli O157:H7) has been developed. This array was able to utilize an HRP‐labeled anti‐E. coli O157:H7 MAb at a concentration of 1:20000 while having a similar sensitivity of 10 5 CFU/ml for E.

A six‐strain mixture of E. coli O157:H7 was exposed to 0 to 9 min of six treatments: (i) hydrostatic pressure (400 MPa) at 4 °C; (ii) hydrostatic pressure and thymol at 4 °C; (iii) thymol at 4 °C; (iv) heat at 40 °C; (v) hydrostatic pressure at 40 °C; and (vi) hydrostatic pressure and thymol at 40 °C.

A novel, label‐free, bidirectional lateral flow immunoassay strip that detected E. coli O157:H7 in food was developed, and it has good specificity, sensitivity, stability, and practicality. The low‐cost and low‐difficulty development of the strip rapid detection technology, which requires neither nano‐labeling materials nor heavily relies on antibodies, may be easier to realize commercialization.

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).

Aims To analyze the non‐glycosylated protein fraction from Melipona beecheii honey for antimicrobial activity against Escherichia coli O157:H7. Methods and Results The proteins from M. beecheii honey were separated according to their degree of glycosylation using Concanavalin A‐affinity chromatography. The total protein extract and its fractions were analyzed by 1D and 2D electrophoresis.

Escherichia coli O157:H7 is regarded as one of the most harmful pathogenic microorganisms related to foodborne diseases. This paper proposes a rapid-detection biosensor for the sensitive and quantitative analysis of E. coli O157:H7 in biological samples by surface-enhanced Raman scattering (SERS)-based lateral flow immunoassay (LFIA).

Many foodborne pathogens including E. coli O157:H7 and Salmonella enterica can develop biofilms on contact surfaces at meat processing plants. Due to the high tolerance of the biofilm cells associated with the 3-dimensional biofilm structure and the well-expressed bacterial polymeric extracellular substances (EPS), it is a real challenge to completely inactivate and remove mature biofilms as well as further prevent biofilm reoccurrence and pathogen survival.

The emergence of multidrug resistant microorganisms represents a global challenge due to the lack of new effective antimicrobial agents. In this sense, essential oils (EOs) are an alternative to be considered because of their anti-inflammatory, antiviral, antibacterial, and antibiofilm biological activities. Therefore, multiple efforts have been made to consider the potential use of EOs in the treatment of infections which are caused by resistant microorganisms.

We compared genomes from multiple isolations of Shiga toxin-producing Escherichia coli (STEC) O157:H7 from the same patient, in cases notified to Public Health England (PHE) between 2015 and 2019. There were 261 cases where multiple isolates were sequenced from the same patient comprising 589 isolates.

In December 2015, six cases of Shiga toxin (Stx)-producing Escherichia coli (STEC) O157:H7 stx2a/stx2c phage type (PT) 24 were identified by the national gastrointestinal disease surveillance system at Public Health England (PHE). Frozen grated coconut imported from India was implicated as the vehicle of infection. Short and long read sequencing data were interrogated for genomic markers to provide evidence that the outbreak strain was from an imported source.

Aims To identify and evaluate the application of two novel monoclonal antibody (mAb) 2G12 against outer membrane protein (Omp) C and mAb 12B1 targeting the O chain of the lipopolysaccharides (LPS) of Escherichia coli O157:H7 (ECO157). Methods and Results The sensitivity and specificity of these two antibodies were evaluated with eight ECO157 strains and 68 untargeted strains.

L. Byrne et al. Signs and symptoms of Shiga toxin–producing Escherichia coli (STEC) serogroup O157:H7 infection range from mild gastrointestinal to bloody diarrhea and hemolytic uremic syndrome (HUS). We assessed the association between Shiga toxin gene (stx) subtype and disease severity for »3,000 patients with STEC O157:H7 in England during 2009–2019.