Recherche scientifique

The impact of oregano (origanum heracleoticum) essential oil and carvacrol on virulence gene transcription by escherichia coli O157:H7

The impact of oregano (origanum heracleoticum) essential oil and carvacrol on virulence gene transcription by escherichia coli O157:H7

Enterohaemorrhagic Escherichia coli (EHEC) serotype O157:H7was first recognized as a food pathogen in 1982 (Paton and Paton 1998). Since then, this organism has been implicated in sporadic cases and outbreaks of enterohaemorrhagic diarrhea worldwide (EFSA and ECDC 2013; Crim et al., 2014). EHEC O157:H7 is a member of the attaching and effacing (A/E) E. coli group. It possesses virulence factors essential for adhesion of the pathogen to intestinal epithelial cells (attachment) and is responsible for the destruction of the brush border ofmicrovilli (effacement) (Paton and Paton 1998).

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Antimicrobial activities of commercial essential oils and their components against food-borne pathogens and food spoilage bacteria

Pathogenic and food spoilage bacteria have been considered as the primary causes of food-borne diseases and food quality deterioration in both developed and developing countries. In order to assure the food safety and to extend the shelf life of food products, additions of chemical preservative agents into food products or decontamination treatments via physical, chemical or biological process or their combinations have been widely applied in food industries (Brul and Coote 1999; Gould 2000). However, critical concerns have been raised due to limitations of treatment processes and since survival of environment-adapted bacteria after treatment processes may lead to high resistance of bacteria such as pathogenic Escherichia coli O157:H7, Listeria monocytogenes, and some Salmonella serovars (Whitney et al. 2007; Hugas and Tsigarida 2008; Rajkovic et al. 2009). Télécharger l'étude complète

Effect of essential oils on the in vitro growth of penicillium digitatum and penicillium italicum infecting citrus and colletotrichum musea infecting banana

Citrus and bananas represent the two economically important fruit crops worldwide. The most important causes of post-harvest losses of these fruits are blue mold caused by Penicillium italicum and green mold caused by Penicillium digitatum for citrus, and anthracnose disease caused by Colletotrichum musea for bananas. To cope with these diseases, treatment with chemical fungicides during the conditioning process has long been used. Nowadays, such a treatment is challenged because of the following reasons: High level of chemical fungicide residues in food products Chemical fungicides toxicity and risk for human health and for the environment, Development of pathogens populations resistant to chemical fungicides, Restriction or ban on use of a number of chemical fungicides by the legislation. This has motivated the search for alternative approaches. Essential Oils (EOs) extracted from aromatic plants are known for their antifungal effects and could thus be used against plant pests. The present work was therefore undertaken to study the effect of ten Eos on the in vitro growth of P. italicum, P.digitatum and C. musea. Télécharger le poster