Research Publications (Food Safety)

A total of 300 food samples including 180 milk and 120 meat products have been examined for the presence of Yersinia sppusing the ISO 10273 and the cold enrichment method. The overall prevalence of Yersinia spp. was 84 (28%). Yersinia enterocolitica was isolated from 18 (6%) of the 300 samples.

Publication date: Available online 12 May 2015

Author(s): Milica Zivkovic , Claudio Hidalgo-Cantabrana , Milan Kojic , Miguel Gueimonde , Natasa Golic , Patricia Ruas-Madiedo

The foodborne bacterial pathogen Campylobacter jejuni is an obligate microaerophile, which is exposed to atmospheric oxygen during transmission through the food chain. Survival under aerobic conditions requires the concerted control of oxidative stress systems, which in C. jejuni are intimately connected with iron metabolism via the PerR and Fur regulatory proteins. Here we have characterised the roles of C.

Abstract

BACKGROUND

Aims
To characterize integron-harbouring Gram-negative bacteria in recreational lakes, with focus on the genetic content of integrons, antimicrobial resistance profiles, and virulence-associated genes.

In Salmonella enterica 1,2-propanediol (1,2-PD) utilization (Pdu) is mediated by a bacterial microcompartment (MCP). The Pdu MCP consists of a multi-protein shell that encapsulates enzymes and cofactors for 1,2-PD catabolism and its role is to sequester a reactive intermediate (propionaldehyde) to minimize cellular toxicity and DNA damage. For the Pdu MCP to function, the enzymes encapsulated within must be provided with a steady supply of substrates and cofactors.

Brucella are intracellular bacterial pathogens that use a type IV secretion system (T4SS) to escape host defenses and create a niche in which they can multiply. Although the importance of Brucella T4SS is clear, little is known about its interactions with host cell structures. In this study, we identified the eukaryotic protein CD98hc as a partner for Brucella T4SS subunit VirB2.

Catrin E. Moore, Phot Nget, Mao Saroeun, Suy Kuong, Seng Chanthou, Varun Kumar, Rachel Bousfield, Johanna Nader, J. Wendi Bailey, Nicholas J. Beeching, Nicholas P. Day, Christopher M. Parry

Background

Gram-negative bacteria survive harmful environmental stressors by modifying their outer membrane. Much of this protection is afforded upon remodeling of the lipid A region of the major surface molecule lipopolysaccharide (LPS). For example, the addition of cationic substituents, such as 4-amino-4-deoxy-L-arabinose (L-Ara4N) and phosphoehthanolamine (pEtN) at the lipid A phosphate groups, is often induced in response to specific environmental flux stabilizing the outer membrane.

The study explores antifungal, anti-aflatoxigenic and antioxidant efficacy of Rosmarinus officinalis essential oil (ROEO) and its major compounds. In addition, the mode of action of ROEO and its practical efficacy as preservative have been assessed. GC-MS analysis of ROEO identified 16 compounds; α-pinene, 1,8-cineole and camphor being the major compounds.

Publication date: Available online 9 May 2015

Author(s): Kjersti Selstad Utaaker , Qirong Huang , Lucy J. Robertson

Lü, Jianhua et al. The ability of the cigarette beetle, Lasioderma serricorne (F.) (Coleoptera: Anobiidae), to infest wheat flour under packaged and unpackaged conditions was investigated in the laboratory at 27 ± 2°C and 75% ± 5% relative humidity. Five common packaging materials, namely, vacuum plastic bags, kraft paper bags, nonwoven cloth bags, aluminum foil bags, and woven plastic bags, were investigated. Adults and eggs of L.

Ko, Sang-Mu et al. Outbreaks of hepatitis A virus (HAV) infections are most frequently associated with the consumption of contaminated oysters. A rapid and selective concentration method is necessary for the recovery of HAV from contaminated oysters prior to detection using PCR.

Hiko, Adem et al. Processing changes the meat ecosystem and, hence, has an impact on the microbiological load and quality of the product. Microbial contamination decreases shelf life and, if a pathogen is present, increases the risk of zoonoses in humans. The aim of this study was to assess the microbiological load, including zoonotic agents, in ready-to-eat beef mortadella from Ethiopian supermarkets.

Bezerra, André Vinícius Andrade et al. Foodborne diseases are a public health problem worldwide. The consumption of contaminated raw milk has been recognized as a major cause of transmission of bovine tuberculosis to humans. Other mycobacteria that may be present in raw milk and may cause diseases are those belonging to the Mycobacterium avium complex. In this study, molecular biology tools were applied to investigate raw milk contamination with Mycobacterium spp.

Cho, Ara et al. Clostridium difficile is an important cause of enteric disease in humans and animals. The prevalence of C. difficile infection is increasing, and the bacterium is frequently found in meat products, suggesting the possibility of animal-to-human transmission. Therefore, food animals must be assessed for their role as reservoirs of C. difficile. In this study, C. difficile was isolated from 2 (0.3%) of 659 slaughtered pigs in Korea.

Lopatek, Magdalena et al. Vibrio parahaemolyticus is a marine bacterium recognized as an important cause of gastroenteritis in humans consuming contaminated shellfish. In recent years, increasing resistance to ampicillin and aminoglycosides has been observed among V. parahaemolyticus isolates. However, the first-line antimicrobials such as tetracyclines and fluoroquinolones remained highly effective against these bacteria. The aim of this study was to evaluate the occurrence of V.

Korsak, Dorota et al. The purpose of the present study was to determine the prevalence of thermophilic Campylobacter in poultry, pork, and beef meat at the retail level and to identify the main categories of meat representing the most significant reservoirs of Campylobacter. A monitoring study was conducted throughout Poland from 2009 to 2013. A total of 1,700 fresh meat samples were collected from supermarkets, large retail outlets, and smaller stores.

Xi, Meili et al. Extended-spectrum β-lactamase (ESBL)–producing Escherichia coli strains have been reported worldwide; however, the incidence and characterization of foodborne ESBL-producing E. coli strains have been rarely reported in the People's Republic of China. Among a collection of 659 E.

Swartz, Richard S. et al. Thermal inactivation of Shiga toxin–producing Escherichia coli (STEC) cells within knitted/cubed beef steaks following cooking on a nonstick griddle was quantified. Both faces of each beef cutlet (ca. 64 g; ca. 8.5 cm length by 10.5 cm width by 0.75 cm height) were surface inoculated (ca.

Wang, Xiwen et al. Cronobacter sakazakii is an emerging pathogen that causes severe and life-threatening conditions including meningitis, bacteremia, and necrotizing enterocolitis. An animal model study for extrapolation of C. sakazakii infection can provide a better understanding of pathogenesis. However, methods for real-time monitoring of the course of C. sakazakii infection in living animals have been lacking. We developed a bioluminescent C.

Tîrziu, Emil et al. The purpose of this study was to investigate the occurrence of Salmonella in raw chicken meat samples collected at the Romanian seaside and to evaluate the antimicrobial susceptibility of the isolates. In 2012, 317 chicken meat samples from slaughterhouses (n = 289) and retail markets (n = 28) were evaluated.

Nguyen, Trang H. D. et al. In recent years, novel nanomaterials have received much attention due to their great potential for applications in agriculture, food safety, and food packaging. Among them, graphene and graphene oxide (GO) are emerging as promising nanomaterials that may have a profound impact on food packaging. However, there are some concerns from consumers and the scientific community about the potential toxicity and biocompatibility of nanomaterials.

Park, Yoen Ju et al. Biofilms are a mixture of bacteria and extracellular products secreted by bacterial cells and are of great concern to the food industry because they offer physical, mechanical, and biological protection to bacterial cells.

Pegoraro, Natália et al. Dry-salted codfish and pollock are commercially important food products with a relatively long shelf life. To date, bacterial assemblages present in these products that are relevant for food safety have been monitored using only classical molecular and/or cultivation methods.