Adherence kinetics, resistance to benzalkonium chloride and microscopic analysis of mixed biofilms formed by Listeria monocytogenes and Pseudomonas putida

Listeria monocytogenes-carrying consortia in food industry. Composition, subtyping and numerical characterisation of mono-species biofilm dynamics on stainless steel

“…Nowadays, bacterial biofilms are well-known to be more resistant to disinfectants and even though it is widely accepted that bacterial species are ubiquitous in the environment, the consideration of multi-species associations for the investigation regarding pathogen control is scarce, despite the fact that the presence of accompanying microbiota producing significant changes in the whole structure has been demonstrated (Giaouris et al, 2014;Norwood and Gilmour, 2000;Saá Ibusquiza et al, 2012;Van der Veen and Abee, 2011). This work aimed to deepen in the knowledge on sessile bacteria present in an actual food-related industrial context so as to use it as a starting point to perform further investigation of efficient pathogen control strategies regarding not only the composition of the biofilms but also the choice of real targets based on interactions among species.…”

“…L. monocytogenes is able to form multispecies biofilms with both Gram positive and Gram negative species (Daneshvar Alavi and Truelstrup Hansen, 2013;Rieu et al, 2008;Van der Veen and Abee, 2011) and the interaction among species forming these consortia varies depending on the genera implicated and the environmental conditions (Van der Veen and Abee, 2011). Various studies involving L. monocytogenes multispecies biofilms have highlighted the complexity of such interactions and the different effects that associated bacteria could have on L. monocytogenes in terms of the number of adhered cells (Carpentier and Chassaing, 2004;Leriche and Carpentier, 2000;Rieu et al, 2008) or the resistance to a sanitisation treatment (Giaouris et al, 2013;Kostaki et al, 2012;Pan et al, 2006;Saá Ibusquiza et al, 2012;Van der Veen and Abee, 2011). Hence it seems to be clear that increasing the knowledge regarding multispecies biofilms could provide key information so as to improve control strategies and reduce food product contamination.…”

A new and efficient method to obtain benzalkonium chloride adapted cells of Listeria monocytogenes

“…In fact, in previous studies BAC-adapted cells were obtained after days or even weeks of culture (Aase et al, 2000;To et al, 2002;Romanova et al, 2006) as it can be observed in the Table 4. Moreover, adapted cells obtained with the proposed method in 2008 had been used during years in subsequent studies (Saá Ibusquiza et al, 2011a, 2011b, 2012 and no reversion in the adaptation to BAC was observed.…”

Adhesion and production of degrading enzymes by bacteria isolated from biofilms in raw milk cooling tanks

“…In the biofilm formation process and in the metabolic activity of a mature biofilm, each microbial species has a quite peculiar role and Pseudomonas, besides being important in contamination of refrigerated raw milk (Ercolini et al, 2007), is one of the active genera in the initial rapid colonization of surfaces. After consolidation of adhesion, it causes significant changes in the physicochemical properties of the surface and probably favors the incorporation of several other species with reduced adhesion capacity (Zottola & Sasahara, 1994;Ibusquiza et al, 2012).…”