Research Publications (Food Safety)

The growing number of Listeria monocytogenes strains displaying increased tolerance to sanitizers widely applied in the food industry is becoming a problem. The aims of this study were to evaluate the susceptibility of L.

Listeria monocytogenes is a ubiquitous foodborne pathogen causing both invasive and non-invasive listeriosis. Sequence type (ST) 9 strains is common in food and food processing environments. In this study, the whole-genome sequences (WGS) of 207 ST9 isolates from different sources, geographical locations (14 countries), and isolated years were analyzed.

In order to prevent food-borne diseases caused by Listeria monocytogenes (L. monocytogenes) safely and effectively, plant essential oils that have no toxic side effects and are not prone to drug resistance have become the focus of research. This article takes basil (Ocimum basilicum L.) essential oil (BEO) as the research object and explores its antibacterial mechanism against L. monocytogenes.

Puroindolines are small, amphipathic, wheat proteins that determine the hardness of the wheat kernel and protect crops from different pathogens. Puroindoline A (PinA) and puroindoline B (PinB) are two major isoforms of puroindolines. These proteins have antibacterial and antifungal properties mainly attributed to their characteristic tryptophan-rich domains (TRDs).

Environmental adaptation of Listeria monocytogenes is a complex process involving various mechanisms that can contribute to their survival in the environment, further spreading throughout the food chain and the development of listeriosis. The aim of this study was to analyze whole-genome sequencing data in a set of 270 strains of L.

While exposure to high levels of toxic metals such as cadmium and arsenic is only experienced in a handful of special habitats and ecosystems, Listeria and other Gram‐positive bacteria have evolved an impressively diverse array of genetic tools for acquiring enhanced tolerance to such metals.

Toxins, Vol. 11, Pages 426: Comparative Analysis of Listeria monocytogenes Plasmids and Expression Levels of Plasmid-Encoded Genes during Growth under Salt and Acid Stress Conditions

Toxins doi: 10.3390/toxins11070426

Authors:
Patricia Hingston
Thomas Brenner
Lisbeth Truelstrup Hansen
Siyun Wang

Abstract

Integrative Analyses of Long Non-coding RNA and mRNA Involved in Piglet Ileum Immune Response to Clostridium perfringens Type C Infection

Journal of Food Safety, EarlyView.

Publication date: 2 February 2019

, Volume 290

Author(s): Dorota Korsak, Cora Chmielowska, Magdalena Szuplewska, Dariusz Bartosik

In this study, the microbiota during industrial rearing, processing, and storage of the edible tropical house cricket, Gryllodes sigillatus, was investigated. To this end, we analyzed samples from the cricket feed, obtained before feeding as well as from the cages, and from the crickets during rearing, after harvest, and after processing into frozen, oven-dried, and smoked and oven-dried (smoked/dried) end products.

In the foodborne pathogen Listeria monocytogenes, arsenic resistance is encountered primarily in serotype 4b clones considered to have enhanced virulence and is associated with an arsenic resistance gene cluster within a 35-kb chromosomal region, Listeria genomic island 2 (LGI2). LGI2 was first identified in strain Scott A and includes genes putatively involved in arsenic and cadmium resistance, DNA integration, conjugation, and pathogenicity.

Abstract

Brochothrix thermosphacta is a dominant but poorly studied meat spoilage organism. It is a close relative of the foodborne pathogen Listeria monocytogenes, and Brochothrix constitutes the second genus in the Listeriaceae family. Here, the genomes of 12 B. thermosphacta strains were sequenced, assembled into draft genomes, characterized, and compared with the genomes of Brochothrix campestris and L. monocytogenes.

Listeria monocytogenes is a foodborne pathogen that can cause severe disease (listeriosis) in susceptible individuals. It is ubiquitous in the environment and often exhibits resistance to heavy metals. One of the determinants that enables Listeria to tolerate exposure to cadmium is the cadAC efflux system, with CadA being a P-type ATPase. Three different cadA genes (designated cadA1 to cadA3) were previously characterized in L. monocytogenes.

Monitoring of dairy products should preferably focus on the most relevant food safety hazards in the dairy supply chain. For this purpose, the possible presence of microbiological, chemical, and physical hazards as well as trends in the dairy supply chain that may affect their presence were assessed. A literature review was combined with available data from EFSA, RASFF, and the Dutch monitoring program on chemical hazards as well as expert information.

Abstract

The inhibition capacity of four combinations of three lactic acid bacteria (LAB) (Lactococcus lactis, Lactobacillus plantarum and Carnobacterium piscicola) has been demonstrated against Listeria monocytogenes in fresh farmed sea bass fillets artificially contaminated. The four combinations gave promising results, having a significant bacteriostatic effect against all tested microflora, during 21 days of vacuum storage at 4 °C.

A new environmental bacterial strain exhibited strong antimicrobial characteristics against methicillin-resistant Staphylococcus aureus, vancomycin-resistant strains of Enterococcus faecalis and Lactobacillus plantarum, and other Gram-positive bacteria. The producer strain, designated OSY-I1, was determined to be Brevibacillus laterosporus via morphological, biochemical, and genetic analyses.

Abstract