次氯酸钠对德尔卑沙门氏菌生物被膜的抑制作用及机制

目的:为控制德尔卑沙门氏菌(Salmonella Derby)在食品加工过程中的污染,研究不同体积分数次氯酸钠对S.Derby生物被膜的抑制作用及其机制.方法:采用结晶紫染色法和平板菌落计数法观察次氯酸钠对生物被膜的抑制和清除效果,进一步观察不同体积分数次氯酸钠作用下沙门氏菌泳动能力和生物被膜内细胞的代谢活性、胞外聚合...

Biofilm Inhibition Activity and Mechanism of Action of Sodium Hypochlorite against Salmonella Derby

Purpose: In order to control the contamination of Salmonella Derby during food processing, the inhibitory effect of different concentrations of sodium hypochlorite on the biofilm formation of Salmonella Derby was studied and the underlying mechanism was investigated. Methods: The crystal violet staining and plate counting methods were used to observe the potential of sodium hypochlorite to inhibit and eradicate Salmonella Derby biofilm, and the content of extracellular polymeric substances (EPS), biofilm metabolism, micromorphology and swimming mobility of Salmonella Derby in the presence of sodium hypochlorite at different concentrations were observed. Results: The minimum inhibitory concentration (MIC) of sodium hypochlorite was 0.08% (V/V), and the sub-MICs (0.04%, 0.02% and 0.01%) of sodium hypochlorite could inhibit the formation of Salmonella Derby biofilm, and also eradicate mature biofilms and the effect of sodium hypochlorite with different sub-MICs was significantly different (P < 0.05). Sodium hypochlorite could significantly reduce biofilm metabolism of Salmonella Derby and inhibit biofilm exopolysaccharide synthesis, and the effect of sodium hypochlorite with different concentrations was significantly different (P < 0.05). The results of confocal laser scanning microscopy (CLSM) showed that sodium hypochlorite treatment greatly reduced the thickness of the biofilm, reduced the number of live bacterial cells, increased the number of dead bacterial cells, and transform the biofilm cells from an aggregated state to a dispersed one. Conclusion: Sodium hypochlorite at different sub-MICs has a significant inhibitory effect on the formation of Salmonella Derby biofilms, possibly by interfering with bacterial growth, metabolism and extracellular polysaccharide secretion.