Biofilm formation by Aeromonas strains under food-related environmental stress conditions

Aeromonas, important human and fish pathogens, can form biofilm on food and food-contact surfaces that may act as a source of cross-contamination in the food-processing facilities. An investigation was undertaken to evaluate the impact of various food-related conditions (media composition, temperature, pH, salt, and food preservatives) on the biofilm formation by 10 different Aeromonas strains, belonging to six species, using polystyrene microtiter plate-based crystal-violet assay. These strains were vastly diverse in their biofilm forming abilities with the majority of them producing weak biofilm in TSB and M9 minimal medium. Among various conditions, majority of the strains formed the highest biofilm at low temperature (10°C) and acidic condition (pH 5). Biofilm formation for most of the strains reduced with an increase in NaCl concentration. The results indicate that various abiotic stresses encountered in food environment affect the production of biofilm in Aeromonas strains and is mainly a strain-specific phenomenon.

Practical applications

The present study reports the biofilm formation by Aeromonas species under different food-related environmental stress conditions. It will help food processors and regulators to optimize prohibitive measures to prevent biofilm formation and reduce the health risks related to biofilm-forming Aeromonas strains.