Research Publications (Food Safety)

Following two O121 STEC outbreaks linked to wheat flour, this study was conducted to gain baseline information on the occurrence of bacterial pathogens and levels of indicator organisms in wheat flour in Canada. A total of 347 pre-packaged wheat flour samples were analyzed for Salmonella spp., Shiga Toxin-Producing Escherichia coli (STEC), Listeria monocytogenes ( L. monocytogenes ) , aerobic colony count (ACC), total coliforms, and generic Escherichia coli ( E. coli ) .

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).

Author(s): Brianmax A. Takundwa, Prashant Bhagwat, Santhosh Pillai, Oluwatosin A. Ijabadeniyi

The hydrolysis of bovine cheese whey (BCW) proteins was performed by the Alcalase immobilized on the support glyoxyl-corn-cob-powder (AGCCP). The whey protein hydrolysates (WPH) obtained with AGCPP were fractionated by RP-HPLC according to the hydrophilicity of the peptides (F1, hydrophilic; F2, intermediate hydrophilicity; and F3, hydrophobic). The fractions were analyzed by MALDI-TOF, and molecular weight peptides (< 1500 m/z) were identified.

Several genes of the eut, pdu, and cob/cbi operons are responsible for the metabolism of ethanolamine (EA) and 1,2-propanediol (PD) and are essential during the pathogenic lifecycles of various enteric pathogens. Studies concerning EA and PD metabolism have primarily focused on bacterial genera from the family Enterobacteriaceae, especially the genus Salmonella.

Author(s): Tareq M. Osaili, Fayeza Hasan, Dinesh Kumar Dhanasekaran, Reyad S. Obaid, Anas A. Al-Nabulsi, Mutamed Ayyash, Layal Karam, Ioannis N. Savvaidis, Richard Holley

Author(s): Veronica Martinez-Rios, Mikael Pedersen, Monica Pedrazzi, Elissavet Gkogka, Jørn Smedsgaard, Paw Dalgaard

Author(s): Tassiana Ramires, Natalie Rauber Kleinubing, Mariana Almeida Iglesias, Helena Reissig Soares Vitola, Adriana Souto Pereira Núncio, Isabela Schneid Kroning, Gustavo Marçal Schmidt Garcia Moreira, Ângela Maria Fiorentini, Wladimir Padilha da Silva

BACKGROUND Eleven Lactobacillus (L.) strains were newly isolated from traditional Turkish Tulum cheeses and were characterized regarding their potential probiotic characteristics (bile and acid tolerance, gastric and pancreatic juice tolerance, lysozyme tolerance, adhesion ability), virulence determinants (haemolytic activity, antibiotic resistance, biogenic amine production), and functional properties (antibacterial activity, β‐galactosidase activity, production of exopolysaccharides, choles

An effective environmental sampling method involves the use of a transport/neutralizing broth with the ability to neutralize sanitizer residues that are collected during sampling and to maintain viability of stressed Listeria monocytogenes (Lm) cells.

Background:L. monocytogenes meningoencephalitis has a mortality rate of up to 50% and neurofunctional sequelae are common. Type I restriction-modification systems (RMS) are capable of adding methyl groups to the host genome. Some contain multiple sequence recognition (hsdS) genes that recombine, resulting in distinct DNA methylation patterns and patterns of gene expression.

Gram-positive bacterial pathogens have an array of proteins on their cell surface that mediate interactions with the host environment. In particular, bacterial cell wall-associated (CWA) proteins play key roles in both colonization and pathogenesis. Furthermore, some CWA proteins promote specialization for host-species or mediate colonization of specific anatomical niches within a host.

Bacteriophages (phages) are currently available for use by the food industry to control the foodborne pathogen Listeria monocytogenes. Although phage biocontrols are effective under specific conditions, their use can select for phage-resistant bacteria that repopulate phage-treated environments. Here, we performed short-term coevolution experiments to investigate the impact of single phages and a two-phage cocktail on the regrowth of phage-resistant L.

Author(s): Luis A. Ibarra-Sánchez, Wentao Kong, Ting Lu, Michael J. Miller

ABSTRACT A fish‐packaging film was prepared with 0.4% gellan gum (GG), 2% citrus pectin (CP), 0.75% glycerol, EDTA 1 mM, and 50 arbitrary‐units (AU)/mL of antimicrobial‐activity supernatants (AS) from Streptococcus infantarius‐cultures containing bacteriocin‐like compounds of 5‐10 kDa.

In this study, the anti‐microbial and anti‐biofilm potential of the cell‐free extract (CFE) of Lactobacillus plantarum was assessed against Listeria monocytogenes 32 isolated from the food sample. CFE of L. plantarum showed high anti‐microbial activity (15.5 ± 1.4 mm diameter zone) against L. monocytogenes 32.

The glycolytic enzyme and bacterial virulence factor of Listeria monocytogenes, the glyceraldehyde-3-phosphate dehydrogenase (GAPDH, Lmo2459), ADP-ribosylated the small GTPase, Rab5a, and blocked phagosome maturation. This inhibitory activity localized within the NAD binding domain of GAPDH at the N-terminal 1–22 peptides, also conferred listeriosis protection when used in dendritic cell-based vaccines. In this study, we explore GAPDH of Listeria, Mycobacterium, and Streptococcus spp.

Author(s): Felice Panebianco, Fi,lippo Giarratana, Andrea Caridi, Rossana Sidari, Alessandra De Bruno, Alessandro Giuffrida

Author(s): Md. Niamul Kabir, Sadiye Aras, Jyothi George, Sabrina Wadood, Shahid Chowdhury, Aliyar Cyrus Fouladkhah

Author(s): Davy Verheyen, Ozan Altin, Dagbjørn Skipnes, Ferruh Erdogdu, Torstein Skåra, Jan F. Van Impe

Author(s): Jasper W. Bannenberg, Tjakko Abee, Marcel H. Zwietering, Heidy M.W. den Besten

This study was aimed at predicting the inactivation of Listeria monocytogenes in cooked beef during unsteady heating. A one‐step approach was firstly applied to determine the thermodynamic coefficient of the beef sample. Then inactivation kinetics were estimated by constructing the empirical heat‐transfer model and the log‐linear dynamic inactivation model. Validations showed that the integrated model could accurately describe L.

Listeria monocytogenes is an opportunistic pathogen with the ability to adapt to different environmental conditions, resulting in safety issues for food producers. Foods contaminated by L. monocytogenes can represent a risk if consumed by susceptible individuals such as elderly, pregnant women and the immunocompromised. The aim of this study was to evaluate the genetic diversity of a collection of L. monocytogenes isolated from different matrices in Brazil during the period of 1979‐2015.

by Caroline Peron-Cane, José-Carlos Fernandez, Julien Leblanc, Laure Wingertsmann, Arnaud Gautier, Nicolas Desprat, Alice Lebreton

This study aimed to explore the antimicrobial effects of activated lactoferrin (ALF) and rosemary extract (RE) on Escherichia coli O157:H7, Salmonella Enteritidis and Listeria monocytogenes, and to investigate their application potential in the meat storage. Minimum inhibitory concentrations (MICs) of ALF, RE and ALF–RE combinations were determined via microtiter plate assay. MICs of ALF were 1% for E.