Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Doctorat → Tunisie → Thèse soutenue → 2020 → The anti-biofilm activity of essential oils on Listeria monocytogenes and Salmonella Enteritidis

Institut National Agronomique de Tunis (INAT) – Université de Carthage (2020)

The anti-biofilm activity of essential oils on Listeria monocytogenes and Salmonella Enteritidis

Somrani Mariem

Titre : The anti-biofilm activity of essential oils on Listeria monocytogenes and Salmonella Enteritidis

Auteur : Somrani Mariem

Etablissement de soutenance : Université Polytechnique de Carthagène, Espagne co tutelle Institut National Agronomique de Tunis (INAT) – Université de Carthage

Grade : Doctorat en Sciences Agronomiques 2020

Résumé partiel
Most foods represent a fertile environment for pathogenic bacteria growth. When the hygienic conditions are missing, the contamination caused by these microorganisms can result in foodborne diseases and outbreaks affecting public health. Also, this contamination can cause important economic losses to food industries in terms of recalls affecting their reputation in the market. For this reason, good hygienic practices have to be held and controlled from farm to fork. In other words, proper disinfection, careful manipulation and the respect of regulations have to be applied during production, processing, shipping, distribution, retail and consumption. Listeria monocytogenes and Salmonella Enteritidis represent two of the most challenging pathogens for food processing environments for different reasons. Listeriosis has a higher fatality rate than other foodborne illnesses and could be mortal for vulnerable groups. Another problem associated with L. monocytogenes, is its ability to grow at refrigeration temperatures, which poses a challenge to food manufacturers and consumers. Salmonella spp. have been predominant in food poisoning outbreaks with S. Enteritidis being the most reported serovar. Also, this microorganism can lead to mild to severe symptoms in humans. Both food pathogens can be introduced in the food chain through raw material, workers and other sources as they habit a wide range of niches. Added to that, they are able to form biofilms on different surfaces making their presence yet very challenging. Biofilms are complex microbial communities formed into an extracellular matrix and they are more resistant forms than their planktonic counterparts. They are formed usually in inaccessible parts of manufacturing plants, as these areas are not well cleaned. Therefore, they can persist for a long time causing problems and contamination. In order to get rid of biofilms, many different cleaning and disinfection protocols have been applied with the use of a wide range of commercial products. However, many of these products can be controversial as they can have various side effects. First, the repetitive use and especially the exposition to sub-inhibitory concentrations can generate resistance by modifying some genes and leading to an increased tolerance. Second, the environmental impact of this kind of chemicals makes them undesirable. Therefore, the investigation for natural alternatives has been increasing every year in order to respond to the consumer’s demands. Among these alternatives, essential oils (EOs) are considered as an eco-friendly and natural option.

Mots Clés  : Listeria monocytogenes ; Salmonella Enteritidis ; biofilm ; essential oil ; cinnamon ; onion ; garlic ; clove

Présentation

Version intégrale

Page publiée le 25 novembre 2022