Search results for "Listeria sp"

Preservation of viability and anti-Listeria activity of lactic acid bacteria, Lactococcus lactis and Lactobacillus paracasei, entrapped in gelling ma…

2015

In order to control undesirable microorganisms growth in foods, the performance of alginate and alginate-caseinate (an aqueous two-phase system) matrices entrapping lactic acid bacteria (LAB) (Lactobacillus paracasei LAB1 and Lactococcus lactis LAB3) was investigated. Polymeric matrices were initially loaded with Lcells at similar to 10(8-10) or similar to 10(4-6) CFU mL(-1), and were monitored, in liquid and gelled form (beads), for 12 days at 30 degrees C. In the liquid form, maximum cell density (similar to 10(9) CFU mL(-1)) was reached after 24 h whatever the matrix. Then, the Lpopulation decreased but remained higher in alginate-caseinate matrices: 10(7) and 10(6) CFU mL(-1) of LAB3 ce…

Listeria spp. in Street-Vended Ready-to-Eat Foods.

2011

Street-vended ready-to-eat food sold in Egypt, including sandwiches and dishes of traditional food, was examined for the presence ofListeriaspecies. Out of 576 samples, 24% were found to containListeriaspecies.L. monocytogenesandL. innocuawere isolated from 57% and 39% of the contaminated samples, respectively. OtherListeriaspp. were detected with lower frequency.L. monocytogenesof ≥103 CFU/g were detected in 7% of the total examined samples, which represent 49% of the contaminated food samples (meat, poultry, seafood, dairy products, and products of plant origin). Most of the samples contaminated byL. monocytogeneshad high levels of total viable bacterial counts. The results obtained may h…

Listeria phage and phage tail induction triggered by components of bacterial-growth media (phosphate, LiCl, nalidixic acid and acriflavine)

2015

ABSTRACT The detection of Listeria monocytogenes from food is currently carried out using a double enrichment. For the ISO methodology, this double enrichment is performed using half-Fraser and Fraser broths, in which the overgrowth of L. innocua can occur in samples where both species are present. In this study, we analyzed the induction of phages and phage tails of Listeria spp. in these media and in two brain heart infusion (BHI) broths (BHIM [bioMérieux] and BHIK [Biokar]) to identify putative effectors. It appears that Na 2 HPO 4 at concentrations ranging from 1 to 40 g/liter with an initial pH of 7.5 can induce phage or phage tail production of Listeria spp., especially with 10 g/lite…

L'influence de désinfectants sur L. monocytogenes en biofilm - Mise en évidence de Listeria spp. dans des aliments au Cambodge

2010

Pārtikas patogēno baktēriju sastopamība dīgstos un diedzētu sēklu produktos

2019

Pieaugot patērētāju pieprasījumam pēc minimāli apstrādātu produktu lietošanas uzturā, pārtikas drošība ir aktuāla un svarīga, īpaši tādiem termiski neapstrādātiem produktiem kā dīgsti. Eiropā Salmonella spp. un Šiga jeb verotoksīnus producējošā Escherichia coli (STEC) ir visbiežāk minētās patogēnās baktērijas, kas izraisījušas uzliesmojumus, kas asociēti ar kontaminētiem dīgstiem. STEC patogenitāti nodrošina patogenitātes gēni stx1, stx2, bet viens no virulences faktoriem kodēts gēnā eaeA. Listeria monocytogenes ir ievērojams piesārņotājs pārtikā, arīdzan tā ir tipiska augsnes baktērija. Jaunākie pētījumi apraksta ne tikai L. monocytogenes, bet arī Listeria innocua patogenitāti. Pētījumā an…

Indigenous Listeria spp. in biowastes and during composting

2007

International audience

Prevalence of Listeria sp. in droppings from urban rooks (Corvus frugilegus)

1997

Droppings from 112 urban rooks (Corvus frugilegus) were cultured for the presence of Listeria sp. Overall, 46% of rooks sampled harboured one or more Listeria species. Of all birds examined, 33%, 24% and 8%, respectively, were infected with Listeria monocytogenes, Listeria innocua and Listeria seeligeri. Differentiation of L. monocytogenes and L. seeligeri carried out by several phenotypic typing methods proved the diversity of strains and the major role of rooks which widely contribute to spreading this bacteria in our environment. The results also suggest that the ability to recover specific Listeria strains from the same sample is at least partially dependent on the methodology. These fi…