The Paradox of Mixed‐Species Biofilms in the Context of Food Safety

Abstract

Formation of mixed-species biofilms constitutes a common adaptation of foodborne pathogens and indigenous microbiota for prolonged survival in their food niche. Nevertheless, the potential role of mixed-species biofilms in food safety remains to be elucidated. The formation of mixed-species biofilms on food and food processing surfaces depends on various physical, chemical, and biological processes including species composition, especially of the indigenous microbiota and nutrients, food types, temperature, quorum sensing, extracellular polymeric substance (EPS) production, biofilms maturation, and dispersal steps. Compared to monospecies, mixed-species are highly resistant to antimicrobials, possibly due to higher EPS production, internalization into food, fitness of species, denser and thicker biofilms maturation, and interspecific protection of 1 species by others, although there are much debate among studies. The fitness of mixed-species biofilms populations is suggested to be of a cooperative, competitive, or neutral nature based on the genetic background of the involved species. Currently, various methods using microarray, confocal microscopy, proteomics, and selective media are being explored for the detection of mixed-species biofilms to resolve the conflict issues. Here, we review recent progress in this emerging field in the context of food safety and propose that novel and alternative techniques like antiquorum sensing, antibiofilms, enzymes, hurdle techniques, and bacteriophages will significantly help to control the formation of mixed-species biofilms for enhanced food safety. The next challenge will be to integrate the fitness and resistance patterns of mixed-species biofilms in the laboratory with those of natural settings.

Formation of In Vitro Mixed-Species Biofilms by Lactobacillus pentosus and Yeasts Isolated from Spanish-Style Green Table Olive Fermentations

“…In vitro, biofilm formation between LAB and yeast species isolated from many foods has been reported (20,(27)(28)(29). In the natural environment of Spanish-style green olive fermentation, mixed-species biofilms between yeasts and lactobacilli in the skins of fruits have also been found (11,12,14,15,19).…”

Characterization of co‐culture of Aeromonas and Pseudomonas bacterial biofilm and spoilage potential on refrigerated grass carp ( Ctenopharyngodon idellu s)

“…Previously, some studies have also reported biofilm formation by some of the Pseudomonas and Aeromonas bacterial strains isolated from different types of foods (i.e., raw milk, fish and meat etc. ; Jahid and Ha 2014; Yuan et al . 2018; Liu et al .…”

Development of a peroxide biodetector for a direct detection of biofilms produced by catalase-positive bacteria on food-contact surfaces

“…In food industry environment, the non-detection of negative catalase microorganisms would not be a problem because biofilms are formed by mixed species (Colagiorgi et al, 2017;Elias & Banin, 2012;Phillips, 2016) and therefore the use of the biodetector would show microbial activity. Biofilms formed by mixed species constitutes a general adaptation of foodborne pathogens and microbiota associated to the food-processing environment for extended survival in their food niche (Jahid & Ha, 2014).…”

“…However, biofilms are formed by multiple microbial species in natural environments (Manuzon & Wang, 2007;Montañez-Izquierdo, Salas-Vázquez, & Rodríguez-Jerez, 2012;Moons, Michiels, & Aertsen, 2009;Percival, Walker, & Hunter, 2000). Different studies have outlined the significance of biofilms formed by mixed species for the food industry (Jahid & Ha, 2014;Percival et al, 2000). The importance for this industry is attributed to the existence of interspecies interactions that might enhance not only the survival of pathogens to sanitizers, disinfectants, UV light, or desiccation, but also its persistence on food-contact surfaces (Lee et al, 2014).…”