Research Publications (Food Safety)

SUMMARY Microbiological contamination of chicken meat depends on the conditions under which the animals are reared, slaughtered and processed. The aim of this study was to determine the influence of farm origin and processing stages at slaughterhouse on the microbial safety and quality of chicken. Samples of chicken carcasses from three different farms were taken from a slaughterhouse.

The type III secretion system (T3SS) consists of a syringe-like export machine injecting effectors from the bacterial cytosol directly into host cells to establish infection. This mechanism is widely distributed in gram-negative bacteria and can be targeted as an innovative strategy for the developing of anti-virulence drugs. In this study, we present an effective T3SS inhibitor, myricanol, inspired by the use of folk medicinal plants traditionally used against infections.

The use of molecular diagnostics for pathogen detection in epidemiological studies have allowed us to get a wider view of the pathogens associated with diarrhea, but the presence of enteropathogens in asymptomatic individuals has raised several challenges in understanding the etiology of diarrhea, and the use of these platforms in clinical diagnosis as well.

The emergence of antimicrobial resistance in the food chain and the consumer's demand for safe food without chemical preservatives have generated much interest in natural antimicrobials. Thus, our main goal was to study the mode of action of the crude extract, the enterocins, and the organic acid produced by a bacteriocinogenic Enterococcus faecium strain S6 previously isolated from raw camel milk. Then, we aimed to evaluate their potential application in a food system.

Bacteriophages use a large number of different bacterial cell envelope structures as receptors for surface attachment. As a consequence, bacterial surfaces represent a major control point for the defense against phage attack. One strategy for phage population control is the production of outer membrane vesicles (OMVs).

Author(s): Gökhan Kürşad İncili, Müzeyyen Akgöl, Mehmet Emin Aydemir, Selçuk Alan, Muhsin Mutlu, Osman İrfan İlhak, Gülsüm Öksüztepe

Rapid and sensitive detection of live/infectious foodborne pathogens is urgently needed in order to prevent outbreaks and food recalls.

The bacteriological diagnosis of intestinal bacterial infections has historically been based on culture on agar plates. However, culture may lack sensitivity, and some enteropathogens, such as pathovars of Escherichia coli, may escape routine diagnosis. Our goal was to evaluate the analytical performance of the Novodiag Bacterial GE+ kit for the detection of enteropathogenic bacteria in acute community diarrhea. We included 251 stools in this study (198 retrospective and 53 prospective).

Determining the viable and non-viable load of foodborne pathogens in animal production can be useful in reducing the number of human outbreaks. In this study, we optimized a PMAxxTM-based qPCR for quantifying viable and non-viable load of Salmonella from soil collected from free range poultry environment. The optimized nucleic acid extraction method resulted in a significantly higher (P < 0.05) yield and quality of DNA from the pure culture and Salmonella inoculated soil samples.

Author(s): Karine Patrin Pontin, Karen Apellanis Borges, Thales Quedi Furian, Daiane Carvalho, Daiane Elisa Wilsmann, Henrique Ribeiro Piaggio Cardoso, Annelise Kopp Alves, Gabriela Zottis Chitolina, Carlos Tadeu Pippi Salle, Hamilton Luiz de Souza Moraes, Vladimir Pinheiro do Nascimento

Typhoid toxin is a virulence factor of Salmonella enterica serovar Typhi, the causative agent of typhoid fever, and is thought to be responsible for the symptoms of severe disease. This toxin has a unique A2B5 architecture with two active subunits, the ADP ribosyl transferase PltA and the DNase CdtB, linked to a pentameric B subunit, which is alternatively made of PltB or PltC.

Successful colonization by enteric pathogens is contingent upon effective interactions with the host and the resident microbiota. These pathogens thus respond to and integrate myriad signals to control virulence. Long-chain fatty acids repress the virulence of the important enteric pathogens Salmonella enterica and Vibrio cholerae by repressing AraC-type transcriptional regulators in pathogenicity islands.

Salmonella enterica serovar Hvittingfoss is an important foodborne serotype of Salmonella, being detected in many countries where surveillance is conducted. Outbreaks can occur, and there was a recent multistate foodborne outbreak in Australia. S. Hvittingfoss can be found in animal populations, though a definitive animal host has not been established.

Author(s): Silvia Guillén, María Marcén, Ignacio Álvarez, Pilar Mañas, Guillermo Cebrián

Author(s): E.G. Olson, L.A. Wythe, D.K. Dittoe, K.M. Feye, S.C. Ricke

Salmonella Enteritidis (SE) is a facultative intracellular pathogen that colonizes the chicken gut leading to contamination of carcasses during processing. A reduction in intestinal colonization by SE could result in reduced carcass contamination thereby reducing the risk of illnesses in humans. Short chain fatty acids such as butyrate are microbial metabolites produced in the gut that exert various beneficial effects. However, its effect on SE colonization is not well known.

The emergence of antimicrobial-resistant (AR) Salmonella has a major concern worldwide. This study was designed to determine the AR profiles and serovars distribution of Salmonella enterica isolated from different breeds of breeder chickens in the province of Henan, China. For this, 2,139 dead embryo samples were collected from 28 breeder chicken hatcheries, representing two domestic and four foreign breeds. The samples were subjected to the isolation and identification of Salmonella by PCR.

Author(s): Abraham Fikru Mechesso, Dong Chan Moon, Su-Jeong Kim, Hyun-Ju Song, Hee Young Kang, Seok Hyeon Na, Ji-Hyun Choi, Ha-Young Kim, Soon-Seek Yoon, Suk-Kyung Lim

Author(s): L.C. Eastwood, T.M. Taylor, J.W. Savell, K.B. Gehring, A.N. Arnold

Author(s): Federica Giacometti, Annalisa Pezzi, Giorgio Galletti, Marco Tamba, Giuseppe Merialdi, Silvia Piva, Andrea Serraino, Silva Rubini

Ultrasound (US) and ozone processing allow achieving food technological aims such as the improvement of food safety and preservation. The combination of these technologies has been reported to be beneficial in inactivating microorganisms from fruits and vegetables. However, treatment conditions and mechanisms of action of these technologies can affect vegetables or fruits structure as well as their phytochemical components.

Author(s): Denes K.A. Rosario, Yhan S. Mutz, Vinicius S. Castro, Patricia C. Bernardes, Andreja Rajkovic, Carlos A. Conte-Junior

Bacterial foodborne diseases are one of the most important public health issues worldwide but in Ecuador reports on the microbiological quality of foods are scarce. In this cross-sectional study, a total of 450 samples of high-demand Ecuadorian food, including bolon, encebollado, sauces, ceviche, fruits, fruit juices, fruit salads, cheese, raw chicken and ground beef were collected from popular street markets in the cities of Guayaquil, Quito and Cuenca.

The differences in the recovery of Salmonella from rendered chicken fat treated with sodium bisulfate (SBS) when inoculated with a dry vs wet inoculum was evaluated. Food grade rendered chicken fat was inoculated with a dry and wet inoculum containing a Salmonella cocktail (S. Enteritidis, S. Heidelberg, and S. Typhimurium). In addition, the effect of an antimicrobial treatment (sodium bisulfate, SBS) against Salmonella spp. in both the aqueous and fat phase of the chicken fat was evaluated.

Salmonella enterica serovar Typhimurium (S. Typhimurium) is exposed to biotic and abiotic stresses. The survival of Salmonella in nature depends on the global regulators like cAMP receptor protein (CRP). The role of CRP in the phenotypic characteristics and stress tolerance was elucidated in S. Typhimurium using a crp gene null mutant (Δcrp).