Biofilm formation by Vibrio parahaemolyticus on different surfaces and its resistance to sodium hypochlorite

ABSTRACT: Vibrio parahaemolyticus is an important pathogen for both fish industry and consumers. It forms biofilm which makes it difficult to eliminate this microorganism using sanitizers. This study aimed to assess biofilm formation on different surfaces and effect of biofilm on resistance to sanitizers. Eight isolates of biofilm-forming V. parahaemolyticus were tested for the ability to form biofilms on a number of surfaces including high density polyethylene, stainless steel, glass, exoskeleton of Farfantepenaeus paulensis (Pink Shrimp), and operculum of Micropogonias furnieri (Whitemouth Croaker). Efficiency of sanitizer sodium hypochlorite against the bacteria was evaluated in the biofilms formed on the surface of the materials used; out the eight strains analyzed four formed biofilm on different surfaces. The present study shows that there are variations between surfaces in terms of biofilm formation, with more than one bacterial strain being able to form biofilm on the surface of the operculum of M. furnieri and on high density polyethylene as well. One isolate formed biofilm on glass, and one isolate formed biofilm on stainless steel. Sanitizers reduced biofilm formation on all surfaces. Based on our findings, we concluded that V. parahaemolyticus isolates have different ability to form biofilm on different surfaces. No isolates formed biofilm on shrimp shells. Results of this study also showed that sodium hypochlorite eat a concentration of 20 parts per million (20ppm) of Cl2, albeit not able to eliminate bacteria reported in biofilms, is still capable of reducing bacterial populations.