Dong Qingli, Sun Linjun, Fang Taisong, Wang Yuan, Li Zhuosi, Wang Xiang, Wu Mengjie, Zhang Hongzhi
School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.
School of Food and Drug, Shanghai Zhongqiao Vocational and Technical University, Shanghai 201514, China.
Foods. 2022 Jun 28;11(13):1917. doi: 10.3390/foods11131917.
This study aims to investigate the mono- and dual-species biofilm formation of Listeria monocytogenes and Pseudomonas aeruginosa incubated in different culture mediums, inoculum ratios, and incubation time. The planktonic cell population and motility were examined to understand the correlation with biofilm formation. The results showed that chicken juice significantly inhibited the biofilm formation of L. monocytogenes (p < 0.05). Pseudomonas aeruginosa was the dominant bacteria in the dual-species biofilm formation in the trypticase soy broth medium. The dynamic changes in biofilm formation were not consistent with the different culture conditions. The growth of planktonic L. monocytogenes and P. aeruginosa in the suspension was inconsistent with their growth in the biofilms. There was no significant correlation between motility and biofilm formation of L. monocytogenes and P. aeruginosa. Moreover, scanning electron microscopy (SEM) results revealed that the biofilm structure of L. monocytogenes was loose. At the same time, P. aeruginosa formed a relatively dense network in mono-species biofilms in an initial adhesion stage (24 h). SEM results also showed that P. aeruginosa was dominant in the dual-species biofilms. Overall, these results could provide a theoretical reference for preventing and controlling the biofilm formation of L. monocytogenes and P. aeruginosa in the food processing environment in the future.
本研究旨在调查在不同培养基、接种比例和培养时间下，单核细胞增生李斯特菌和铜绿假单胞菌的单物种和双物种生物膜形成情况。检测浮游细胞数量和运动性，以了解其与生物膜形成的相关性。结果表明，鸡肉汁显著抑制了单核细胞增生李斯特菌的生物膜形成（p < 0.05）。在胰蛋白酶大豆肉汤培养基中，铜绿假单胞菌是双物种生物膜形成中的优势菌。生物膜形成的动态变化与不同培养条件不一致。悬浮液中浮游的单核细胞增生李斯特菌和铜绿假单胞菌的生长与其在生物膜中的生长不一致。单核细胞增生李斯特菌和铜绿假单胞菌的运动性与生物膜形成之间无显著相关性。此外，扫描电子显微镜（SEM）结果显示，单核细胞增生李斯特菌的生物膜结构疏松。同时，在初始黏附阶段（24小时），铜绿假单胞菌在单物种生物膜中形成了相对致密的网络。SEM结果还表明，在双物种生物膜中铜绿假单胞菌占主导地位。总体而言，这些结果可为未来食品加工环境中单核细胞增生李斯特菌和铜绿假单胞菌生物膜形成的防控提供理论参考。
