Purpose: We investigated the correlation of variability of biofilm, quorum sensing and motility of 22 strains of V. parahaemolyticus on the stainless steel (SS) surface.
Methods: Biofilm formation index (BFI) assay, motility assay, autoinducer 2 (AI-2) assay, exoprotease assay and field emission scanning electron microscopy (FESEM) analysis were used as the indexes to determine any correlation between biofilm formation and motility/quorum sensing of V. parahaemolyticus on stainless steel surface. The student t-test was used to analyze for Pearson correlation between two indexes.
Results: The strains VP 4 (oyster isolates), VP 9 (warty squid isolates) and VP 13 (mussel isolates) were highest biofilm former among 22 strains of V. parahaemolyticus based on the BFI and FESEM. The swimming motility showed positive correlation (39.5%) with the formation of biofilm than swarming motility (-0.12%) in varieties of V. parahaemolyticus strains. The biofilm forming ability of V. parahaemolyticus strains was dependent on quorum sensing. We observed 72.8% positive correlation between SS biofilm and AI-2 and 60.6% positive correlation between SS biofilm and exoprotease production.
Significance: This study found that the biofilm forming ability of V. parahaemolyticus strains was dependent on quorum sensing and motility. These findings afford useful information in understanding of strain variability, besides in strain selection for exploitation in the context of food safety challenge and to determine the ability to form biofilms. These insights in biofilm formation features will permit us to further optimize approaches to control the biofilm formation of V. Parahaemolyticus.