紫外发光二极管对P.deceptionensis CM2杀菌作用及机制

Effect of Ultraviolet-C Iight-Emitting Diodes on P.deceptionensis CM2:Inactivation Efficiency and Mechanism

研究紫外发光二极管(UVC-LEDs)处理对假单胞菌CM2(P.deceptionensis CM2)的灭活作用及机理。结果表明,UVC-LEDs处理对P.deceptionensis CM2具有良好灭活效果,且灭活效果随处理剂量升高而增强。处理剂量8 mJ/cm^(2)和4000 mJ/cm^(2)时,纯培养体系和鸡肉表面P.deceptionensis CM2分别降低6.09 log10 CFU/mL和2.45log10 CFU/g。场发射扫描电镜(FE-SEM)结果表明,经UVC-LEDs(4000 mJ/cm^(2))处理后,P.deceptionensis CM2细胞形态发生明显皱缩。随着处理剂量(1000~4000 mJ/cm^(2))的增加,P.deceptionensis CM2细胞中碘化丙啶荧光强度显著增强,胞外核酸和蛋白含量显著增加。以上结果表明,UVC-LEDs杀菌作用可能与细胞结构破坏、细胞膜通透性增加有关。试验结果为UVC-LEDs在食品安全控制和保鲜领域的应用提供参考。

This work aimed to investigate the inactivation efficiency and mechanisms of ultraviolet-C light-emitting diodes(UVC-LEDs)against P.diceptionensis CM2.After UVC-LEDs treatment,the populations of P.deceptionensis CM2 significantly decreased with increasing UVC-LEDs dose.At doses of 8 mJ/cm^(2)and 4000 mJ/cm^(2),the numbers of P.deceptionensis CM2 in pure culture system and on chicken breast decreased by 6.09 log10 CFU/mL and 2.45 log10 CFU/g,respectively.As revealed by field emission scanning electron microscopy(FE-SEM),UVC-LEDs treatment at 4000 mJ/cm^(2)resulted in obvious shrink in morphology of P.deceptionensis CM2 cells.With increasing doses of 1000 to 4000 mJ/cm^(2),the propidium iodide fluorescence intensity and the contents of extracellular nucleic acid and protein of P.deceptionensis CM2 significantly increased.In summary,the bactericidal effect of UVC-LEDs may be associated with the changes of cell structure and the membrane permeability.This work provided basis for the application of UVC-LEDs in the food safety control and preservation.