Antibiofilm effect of sodium butyrate against Vibrio parahaemolyticus

Vibrio parahaemolyticus (V. parahaemolyticus) is an important foodborne pathogen, which is frequently associated with seafood consumption and commonly causes gastroenteritis. The biofilm formed by V. parahaemolyticus in the food production chain poses a continuous threat to food safety, therefore effective antibiofilm strategy is in urgent need. Sodium butyrate is widely used in food, feed, cosmetics and other industries, and could be used as a flavoring agent in food as well as a dietary supplement for health. This study aims to examine the antibiofilm effect of sodium butyrate against V. parahaemolyticus. We found that sodium butyrate could inhibit biofilm formation at subinhibitory concentrations (SICs). Microscopic images coupled with extracellular polysaccharide quantification showed that V. parahaemolyticus biofilm was loosely structured with fewer biofilm constituents when treated with sodium butyrate. XTT reduction assay illustrated that sodium butyrate interfered with the metabolic activity of cells encased inside biofilm and decreased their viability. Sodium butyrate decreased the motility and surface hydrophobicity of V. parahaemolyticus, and interfered with quorum sensing by using two reporter strains. The RT-qPCR analysis revealed that sodium butyrate down-regulated genes associated with biofilm formation. These findings suggest that sodium butyrate has the potential to be developed as a potent agent against V. parahaemolyticus biofilm in food industries.