Research Publications (Food Safety)

Elaine M. S. Dorneles, Graciela K. Lima, Andréa Teixeira-Carvalho, Márcio S. S. Araújo, Olindo A. Martins-Filho, Nammalwar Sriranganathan, Hamzeh Al Qublan, Marcos B. Heinemann, Andrey P. Lage

Publication date: Available online 9 September 2015

Author(s): Linda Falgenhauer, Hiren Ghosh, Beatriz Guerra, Yancheng Yao, Moritz Fritzenwanker, Jennie Fischer, Reiner Helmuth, Can Imirzalioglu, Trinad Chakraborty

Saxitoxins (STX), neurotoxic alkaloids, fall under the umbrella of Paralytic Shellfish Toxins (PSTs) produced by marine dinoflagellates and freshwater cyanobacteria. The genes responsible for the production of saxitoxin have been proposed, but factors that influence their expression and induce toxin efflux remain unclear. Here we characterise the putative STX NorM-like MATE transporters SxtF and SxtM.

Bacterial proteases contribute to virulence by cleaving host or bacterial proteins to promote survival and dissemination. Omptins are a family of proteases embedded in the outer-membrane of Gram-negative bacteria that cleave various substrates, including host antimicrobial peptides, with a preference for cleaving at dibasic motifs. OmpT, the enterohemorrhagic Escherichia coli (EHEC) omptin, cleaves and inactivates the human cathelicidin LL-37.

Enteropathogenic Escherichia coli (EPEC) are human pathogens that require initial adhesion to the intestine in order to cause disease. Multiple adhesion factors have been identified in E. coli strains and among them, the long polar fimbriae (Lpf), a colonization factor associated with intestinal adhesion. The conditions of Lpf expression are well understood in enterohemorrhagic E.

Botulinum neurotoxins (BoNTs) produced by the anaerobic bacterium Clostridium botulinum are the most potent biological substances known to mankind. BoNTs are the agents responsible for botulism, a rare condition affecting the neuromuscular junction, causing a spectrum of diseases from mild cranial nerve palsies to acute respiratory failure and death.

Publication date: 23 December 2015
, Volume 215
Author(s): Hyun-Sun Seo, Larry R. Beuchat, Hoikyung Kim, Jee-Hoon Ryu

Publication date: 23 December 2015
, Volume 215
Author(s): Prashant Singh, Azlin Mustapha

Abstract

Foodborne Pathogens and Disease , Vol. 0, No. 0.

Abstract

Publication date: 23 December 2015
, Volume 215
Author(s): Ewa Pacholewicz, Apostolos Liakopoulos, Arno Swart, Betty Gortemaker, Cindy Dierikx, Arie Havelaar, Heike Schmitt

Fungus-growing termites rely on symbiotic microorganisms to help break down plant material and to obtain nutrients. Their fungal cultivar, Termitomyces, is the main plant degrader and food source for the termites, while gut bacteria complement Termitomyces in the degradation of foodstuffs, fixation of nitrogen, and metabolism of amino acids and sugars.

Broiler chicken litter was kept as a stacked heap on a poultry farm, and samples were collected up to 9 months of storage. Chicken litter inoculated with desiccation-adapted Salmonella cells was heat-treated at 75, 80, 85, and 150°C. Salmonella populations decreased in all these samples during heat treatment, and the inactivation rates became lower in chicken litter when storage time was extended from 0 to 6 months.

The foodborne pathogen Listeria monocytogenes is able to survive and grow in ready-to-eat foods, in which it is likely to experience a number of environmental stresses due to refrigerated storage and the physicochemical properties of the food. Little is known about the specific molecular mechanisms underlying survival and growth of L. monocytogenes under different complex conditions on/in specific food matrices.

Common salt (NaCl) is frequently used by the food industry to add flavor and to act as a humectant in order to reduce the water content of a food product. The improved health awareness of consumers is leading to a demand for food products with reduced salt content; thus, manufacturers require alternative water activity-reducing agents which elicit the same general effects as NaCl. Two examples include KCl and glycerol.

Synthetic genes based on deduced amino acid sequences of the NAD-dependent DNA ligase (ligA) and CTP synthetase (pyrG) of psychrophilic bacteria were substituted for their native homologues in the genome of Salmonella enterica serovar Enteritidis phage type 13a (PT13a). The resulting strains were rendered temperature sensitive (TS) and did not revert to temperature resistance at a detectable level.

A starter culture composed of Pediococcus pentosaceus, Lactobacillus sakei and Staphylococcus xylosus isolated from Chinese-fermented sausages was used to manufacture fermented sausages. The effects of the starter culture on histamine accumulation, nitrite depletion, lipid oxidation and quality parameters including pH, water activity and total volatile base nitrogen (TVB-N), as well as the color and texture properties, were evaluated.

Publication date: Available online 3 September 2015

Author(s): Geik Yong Ang, Choo Yee Yu, Kok Gan Chan, Kirnpal Kaur Banga Singh, Chan Yean Yean

Publication date: Available online 3 September 2015

Author(s): Chen Zhang, Peihua Niu, Yanying Hong, Ji Wang, Jingyun Zhang, Xuejun Ma

In 2006, a deadly Escherichia coli O157:H7 outbreak in bagged spinach was traced to California’s Central Coast region, where >70% of the salad vegetables sold in the United States are produced. Although no definitive cause for the outbreak could be determined, wildlife was implicated as a disease vector. Growers were...

Publication date: 23 December 2015
, Volume 215
Author(s): Lorraine Endersen, Aidan Coffey, R. Paul Ross, Olivia McAuliffe, Colin Hill, Jim O'Mahony

Hilo Yen, Nakaba Sugimoto, Toru Tobe

Mass spectrometry has recently become a powerful technique for bacterial identification. Mass spectrometry approaches generally rely upon introduction of the bacteria into a matrix-assisted laser-desorption time-of-flight (MALDI-TOF) mass spectrometer with mass spectrometric recognition of proteins specific to that organism that form a reliable fingerprint.

About 1.5(v/v) thyme and clove essential oils were added to 1.5% (w/v) sorbitol-amended whey isolate-based film. These films were used for coating traditional semi-hard kashar cheese (traditional Turkish cheese). Escherichia coli O157:H7, Listeria monocytogenes and Staphylococcus aureus microorganisms were selected for the determination of antimicrobial properties of the films by artificial contamination.