Involvement of bacterial quorum sensing signals in spoilage potential ofAeromonas veroniibv.veroniiisolated from fermented surimi

Abstract

This study characterized the spoilage potential of the N-acyl homoserine lactone (AHL)-producing strain, Aeromonas veronii bv. veronii, isolated from fermented surimi, and investigated the effects of exogenous AHLs on its spoilage characteristics. The strain showed a strong ability of producing total volatile base nitrogen (TVB-N) and putrescine, and four types of AHLs, including N-butanoyl-L-homoserine lactone (C4-HSL), N-hexanoyl-L-homoserine lactone (C6-HSL), N-heptanoyl-L-homoserine lactone (C7-HSL), and N-octanoyl-L-homoserine lactone (C8-HSL), were identified from the supernatant by LC–MS/MS. Concentrations of AHLs reached the maximum value as the cells entered stationary phase contents and then decreased rapidly with the increasing pH. C8-HSL was found to be dominant with contents of 1,536.33 ng/mL and exogenous C8-HSL was most effective in promoting bacterial growth, biofilm formation, swimming motility, production of TVB-N and putrescine, and relative genes expression. The results indicated the involvement of AHL-based quorum sensing system in the regulation of spoilage potential of Aeromonas spp. Practical applications The results of the present study found that Aeromonas veronii bv. veronii was capable of producing four types of AHLs, which were considered to be involved in the regulation of spoilage potential of the strain. This would enrich the understanding of quorum sensing system in Aeromonas and give clue for new strategy of controlling food spoilage in food industry.