Behaviour of Listeria monocytogenes and Yersinia enterocolitica during beef dry-aging up to 60 days.

The Commission delegated Regulation (EU) 2024/1141 states that beef dry aging can be performed in a dedicated cabinet, at a surface temperature of -0.5 to 3 °C, maximum relative humidity of 85 %, air speed of 0.2-0.

Evaluation of two real-time PCR methods to detect Yersinia enterocolitica in bivalve molluscs collected in Campania region.

Yersinia enterocolitica (Ye) is a foodborne pathogen isolated from humans, food, animals, and the environment. Yersiniosis is the third most frequently reported foodborne zoonosis in the European Union. Ye species are divided into six biotypes 1A, 1B, 2, 3, 4, and 5, based on biochemical reactions and about 70 serotypes.

Investigation of Salmonella, hepatitis E virus (HEV) and viral indicators of fecal contamination in four Italian pig slaughterhouses, 2021-2022.

In the pork production chain, the control at slaughterhouse aims to ensure safe food thanks to proper hygienic conditions during all steps of the slaughtering. Salmonella is one of the main foodborne pathogens in the EU causing a great number of human cases, and pigs also contribute to its spreading. Pig is the main reservoir of the zoonotic hepatitis E virus (HEV) that can be present in liver, bile, feces and even rarely in blood and muscle.

Molecular characterization of Yersinia enterocolitica strains to evaluate virulence associated genes.

Introduction: Yersinia enterocolitica (Ye) species is divided into 6 biotypes (BT), 1A, 1B, 2, 3, 4, 5 classified based on biochemical reactions and about 70 serotypes, classified based on the structure of the lipopolysaccharide O-antigen. The BT1A is considered non-pathogenic, while the BT 1B-5 are considered pathogenic.

Methods: Evaluate the distribution of eleven chromosomal and plasmid virulence genes, ail, ystA, ystB, myfA, hreP, fes, fepD, ymoA, sat, virF and yadA, in 87 Ye strains isolated from food, animals and humans, using two SYBR Green real-time PCR platforms.

Enhancement of CRISPR/Cas12a trans-cleavage activity using hairpin DNA reporters.

The RNA programmed non-specific (trans) nuclease activity of CRISPR-Cas Type V and VI systems has opened a new era in the field of nucleic acid-based detection. Here, we report on the enhancement of trans-cleavage activity of Cas12a enzymes using hairpin DNA sequences as FRET-based reporters. We discover faster rate of trans-cleavage activity of Cas12a due to its improved affinity (Km) for hairpin DNA structures, and provide mechanistic insights of our findings through Molecular Dynamics simulations.

Presence of enteric bacterial pathogens in meat samples of wild boar hunted in Campania region, southern Italy.

Wild boars can be infected with several foodborne pathogens which may be transmitted to humans through the consumption of their meat, but currently, data of their prevalence are still limited. The present study aimed to evaluate the presence of enteric pathogens in wild boar meat samples killed in the Campania region. Twentyeight wild boar meat samples were analyzed for the detection of spp, , spp.

Protein-Protein Communication Mediated by an Antibody-Responsive DNA Nanodevice.

We report here the rational design and optimization of an antibody-responsive, DNA-based device that enables communication between pairs of otherwise non-interacting proteins. The device is designed to recognize and bind a specific antibody and, in response, undergo a conformational change that leads to the release of a DNA strand, termed the "translator," that regulates the activity of a downstream target protein. As proof of principle, we demonstrate antibody-induced control of the proteins thrombin and Taq DNA polymerase.

Association of Polygenic Risk Score and Bacterial Toxins at Screening Colonoscopy with Colorectal Cancer Progression: A Multicenter Case-Control Study.

Colorectal cancer (CRC) is a leading cause of cancer death worldwide, and its incidence is correlated with infections, chronic inflammation, diet, and genetic factors. An emerging aspect is that microbial dysbiosis and chronic infections triggered by certain bacteria can be risk factors for tumor progression. Recent data suggest that certain bacterial toxins implicated in DNA attack or in proliferation, replication, and death can be risk factors for insurgence and progression of CRC.

Fresh produce and microbial contamination: persistence during the shelf life and efficacy of domestic washing methods.

The transmission of enteric pathogens by fresh produce depends on the survival of the bacteria organisms during the product shelf-life. The removal of any potentially hazardous microorganism from the vegetables is therefore dependent on the washing and sanitizing techniques employed by individual households. For this purpose, in this work we investigated the persistence of enteric bacteria, using as model Salmonella enterica serovar Napoli (S.

Electrochemical Biosensors for Rapid Detection of Foodborne Salmonella: A Critical Overview.

has represented the most common and primary cause of food poisoning in many countries for at least over 100 years. Its detection is still primarily based on traditional microbiological culture methods which are labor-intensive, extremely time consuming, and not suitable for testing a large number of samples. Accordingly, great efforts to develop rapid, sensitive and specific methods, easy to use, and suitable for multi-sample analysis, have been made and continue.

Evaluation of virulence genes in Yersinia enterocolitica strains using SYBR Green real-time PCR.

Yersinia enterocolitica comprises six biotypes 1A, 1B, 2, 3, 4, and 5. The virulence of the strains belonging to biotypes 1B and 2-5 depends on the presence of both chromosomal and plasmid-borne genes. Strains belonging to biotype 1A do not carry the virulence plasmid pYV.

Optimization of a Real Time PCR based method for the detection of Listeria monocytogenes in pork meat.

The aim of this study was to optimize a Real-Time PCR protocol for a rapid detection of Listeria monocytogenes in pork meat, using reduced volumes of primary selective enrichment broth and times of incubation to decrease the cost and time for analysis. Forty-five samples of pork meat were artificially contaminated with two different levels of L. monocytogenes (1-10 CFU per sample and 10-100 CFU per sample), homogenized in three different volumes of Half Fraser Broth (1:3; 1:5 and 1:10) and incubated at 30°C ± 1°C for 5h, 8h and 24h.

Next day Salmonella spp. detection method based on real-time PCR for meat, dairy and vegetable food products.

The microbiological standard for detection of Salmonella relies on several cultural steps and requires more than 5 days for final confirmation, and as consequence there is a need for an alternative rapid methodology for its detection. The aim of this study was to compare different detection strategies based on real-time PCR for a rapid and sensitive detection in an ample range of food products: raw pork and poultry meat, ready to eat lettuce salad and raw sheep milk cured cheese. Three main parameters were evaluated to reduce the time and cost for final results: the initial sample size (25 and 50 g), the incubation times (6, 10 and 18 h) and the bacterial DNA extraction (simple boiling of the culture after washing the bacterial pellet, the use of the Chelex resin, and a commercial silica column).

First isolation of Salmonella enterica serovar Napoli from wild birds in Italy.

Salmonella enterica serovar Napoli (S. Napoli) is an emerging serovar in Italy. It accounts for 2-4% of all serovars isolated from human infections.

Is capillary electrophoresis on microchip devices able to genotype uridine diphosphate glucuronosyltransferase 1A1 TATA-box polymorphisms?

In this commentary, we focused our attention on capillary electrophoresis. It achieves the efficient separation of molecular species by the application of high voltages to samples in solution. Actually, capillary electrophoresis can be performed on microchip devices, based on an automated and miniaturized electrophoresis system, based on lab-on-a-chip technology.

European validation of Real-Time PCR method for detection of Salmonella spp. in pork meat.

The classical microbiological method for detection of Salmonella spp. requires more than five days for final confirmation, and consequently there is a need for an alternative methodology for detection of this pathogen particularly in those food categories with a short shelf-life. This study presents an international (at European level) ISO 16140-based validation study of a non-proprietary Real-Time PCR-based method that can generate final results the day following sample analysis.

European validation of a real-time PCR-based method for detection of Listeria monocytogenes in soft cheese.

The classical microbiological method for detection of Listeria monocytogenes requires around 7 days for final confirmation, and due to perishable nature of RTE food products, there is a clear need for an alternative methodology for detection of this pathogen. This study presents an international (at European level) ISO 16140-based validation trial of a non-proprietary real-time PCR-based methodology that can generate final results in the following day of the analysis. This methodology is based on an ISO compatible enrichment coupled to a bacterial DNA extraction and a consolidated real-time PCR assay.

Multiplex real-time PCR SYBR Green for detection and typing of group III Clostridium botulinum.

Clostridium botulinum type C and type D belonging to the group III organisms, are mainly responsible for animal botulism outbreaks. Clinical signs alone are often insufficient to make a diagnosis of botulism and a laboratory confirmation is required. Laboratory confirmation can be performed by demonstrating the presence of botulinum neurotoxins in serum, gastrointestinal contents, liver, wound of sick or dead animals, or by demonstrating the presence of C.

Comparison between two standardized cultural methods and 24 hour duplex SYBR green real-time PCR assay for Salmonella detectionin meat samples.

Food-borne diseases caused by Salmonella represent a worldwide public health problem. Salmonella must be absent in an established amount depending on the kind of the product and usually cultural methods have to be applied to evaluate the compliance of the products. ISO 6579:2002 in Europe and FSIS MLG 4.

Towards an international standard for detection and typing botulinum neurotoxin-producing Clostridia types A, B, E and F in food, feed and environmental samples: a European ring trial study to evaluate a real-time PCR assay.

A real-time PCR method for detection and typing of BoNT-producing Clostridia types A, B, E, and F was developed on the framework of the European Research Project "Biotracer". A primary evaluation was carried out using 104 strains and 17 clinical and food samples linked to botulism cases. Results showed 100% relative accuracy, 100% relative sensitivity, 100% relative specificity, and 100% selectivity (inclusivity on 73 strains and exclusivity on 31 strains) of the real-time PCR against the reference cultural method combined with the standard mouse bioassay.

PCR experion automated electrophoresis system to detect Listeria monocytogenes in foods.

Listeria monocytogenes is frequently found as a contaminant in raw and ready-to-eat foods. The ability of L. monocytogenes to multiply at refrigeration temperatures and to grow in a wide range of pH values is of particular concern for food safety.

Multiplex PCR for detection of botulinum neurotoxin-producing clostridia in clinical, food, and environmental samples.

Botulinum neurotoxin (BoNT), the most toxic substance known, is produced by the spore-forming bacterium Clostridium botulinum and, in rare cases, also by some strains of Clostridium butyricum and Clostridium baratii. The standard procedure for definitive detection of BoNT-producing clostridia is a culture method combined with neurotoxin detection using a standard mouse bioassay (SMB). The SMB is highly sensitive and specific, but it is expensive and time-consuming and there are ethical concerns due to use of laboratory animals.