Efficient isolation of Campylobacter bacteriophages from chicken skin, analysis of several isolation protocols.

The application of Campylobacter specific bacteriophages appears as a promising food safety tool for the biocontrol of this pathogen in the poultry meat production chain. However, their isolation is a complicated challenge since their occurrence appears to be low. This work assessed the efficiency of seven protocols for recovering Campylobacter phages from chicken skin samples inoculated at phage loads from 5.

Static and Continuous flow-through pulsed light technology for pesticide abatement in water.

Perspectives concerning pulsed light (PL) technology as a novel water decontamination treatment are overviewed in this work. Degradation of atrazine, malathion, chlorpyriphos-methyl and bromopropylate in aqueous solutions at different concentrations was performed employing static and continuous flow-through PL units. Results for both PL systems were compared in terms of efficacy of pesticides degradation and derived photoproducts formed.

Survival and growth of Listeria innocua treated by pulsed light technology: impact of post-treatment temperature and illumination conditions.

Inactivation of Listeria innocua by pulsed light (PL) was evaluated at different post-treatment temperature and illumination conditions. The impact of post-PL-treatment temperature on L. innocua culturability was evaluated for cells cultured at 37 °C (optimal growth temperature) and 4 °C (classical refrigerated food temperature).

Sensitivity to pulsed light technology of several spoilage and pathogenic bacteria isolated from fish products.

The effect of pulsed light (PL) on the inactivation of six fish spoilage bacteria (Photobacterium phosphoreum, Serratia liquefaciens, Shewanella putrefaciens, Brochothrix thermosphacta, Pseudomonas group I, and Pseudomonas groups III and IV), six Listeria monocytogenes isolates from fish products, and one strain of Listeria innocua was evaluated. For all tested strains, grown at 4°C (temperature to process, store, and distribute convenient, lightly preserved fish products), the maximum detectable inactivation (6 to 6.5 log) was observed after treatments lower than 0.

Antimicrobial assays of natural extracts and their inhibitory effect against Listeria innocua and fish spoilage bacteria, after incorporation into biopolymer edible films.

The antimicrobial activity of twelve natural extracts was tested against two fish spoilage bacteria (Pseudomonas fluorescens and Aeromonas hydrophila/caviae) and Listeria innocua, in order to assess their potential utilization in the preservation and safety of minimally processed fish products. After a screening of the active extracts by agar diffusion and vapour diffusion methods, oregano and thyme essential oils and citrus extract were selected. The minimum inhibitory concentration (MIC) of the selected extracts was determined by disc diffusion method against target bacteria and at two temperatures: bacteria's optimal growth temperature (30 °C or 37 °C) and refrigeration temperature (4 °C).

Fast atrazine photodegradation in water by pulsed light technology.

Pulsed light technology consists of a successive repetition of short duration (325μs) and high power flashes emitted by xenon lamps. These flashlamps radiate a broadband emission light (approx. 200-1000 nm) with a considerable amount of light in the short-wave UV spectrum.

Microencapsulation of a probiotic and prebiotic in alginate-chitosan capsules improves survival in simulated gastro-intestinal conditions.

Chitosan was used as a coating material to improve encapsulation of a probiotic and prebiotic in calcium alginate beads. Chitosan-coated alginate microspheres were produced to encapsulate Lactobacillus gasseri (L) and Bifidobacterium bifidum (B) as probiotics and the prebiotic quercetin (Q) with the objective of enhancing survival of the probiotic bacteria and keeping intact the prebiotic during exposure to the adverse conditions of the gastro-intestinal tract. The encapsulation yield for viable cells for chitosan-coated alginate microspheres with quercetin (L+Q and B+Q) was very low.

Determination of cells' water membrane permeability: unexpected high osmotic permeability of Saccharomyces cerevisiae.

Water permeability (Lp), calculated from the volume variations of cells subjected to an osmotic shock, is classically used to characterize cell membrane properties. In this work, we have shown the importance of the kind of mixing reactor used to measure the Lp parameter. A mathematical model including the mixing time constant has been proposed allowing an accurate Lp estimation even though the mixing time constant is higher than the cell time constant obtained in response to a perfect shock.

Evaluation of an extracting method for the detection of Hepatitis A virus in shellfish by SYBR-Green real-time RT-PCR.

Consumption of virus-contaminated shellfish has caused numerous outbreaks of gastroenteritis and hepatitis worldwide. In the present study, we evaluated a rapid and simple extraction method to concentrate and purify enteric viruses from shellfish tissues for their detection by real-time RT-PCR. This procedure consists of an alkaline elution with a glycine buffer, solids removal by slow speed centrifugation, purification by chloroform extraction and virus concentration by ultracentrifugation.