Department of Food Hygiene and Technology, Veterinary Faculty, University of León, E-24071, León, Spain; Institute of Food Science and Technology, University of León, E-24071, León, Spain.
Department of Food Hygiene and Technology, Veterinary Faculty, University of León, E-24071, León, Spain; Facultad de Ciencias de la Salud, Universidad Isabel I, E-09003, Burgos, Spain.
Food Microbiol. 2021 Apr;94:103616. doi: 10.1016/j.fm.2020.103616. Epub 2020 Aug 8.
The objective of this study was to characterize the biofilms formed by Salmonella enterica serotype Agona, Listeria monocytogenes, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium (VRE) after 12, 48, 72, 120 and 240 h of incubation at 10 °C. Biofilms containing a single species, together with dual-species biofilms in which S. enterica and a Gram-positive bacterium existed in combination, were formed on polystyrene and evaluated by using confocal laser scanning microscopy (CLSM). All strains were able to form biofilm. The greatest biovolume in the observation field of 14,161 μm was observed for mono-species biofilms after 72 h, where biovolumes of 94,409.0 μm ± 2131.0 μm (S. enterica), 58,418.3 μm ± 5944.9 μm (L. monocytogenes), 68,020.8 μm ± 5812.3 μm (MRSA) and 59,280.0 μm ± 4032.9 μm (VRE) were obtained. In comparison with single-species biofilms, the biovolume of S. enterica was higher in the presence of MRSA or VRE after 48, 72 and 120 h. In dual-species biofilms, the bacteria showed a double-layer distribution pattern, with S. enterica in the top layer and Gram-positive bacteria in the bottom layer. This spatial disposition should be taken into account when effective strategies to eliminate biofilms are being developed.
本研究的目的是在 10°C 下分别孵育 12、48、72、120 和 240 小时后，对肠炎沙门氏菌血清型阿贡纳、单核细胞增生李斯特菌、耐甲氧西林金黄色葡萄球菌（MRSA）和万古霉素耐药粪肠球菌（VRE）形成的生物膜进行特征描述。在聚苯乙烯上形成了含有单一物种的生物膜，以及在含有单一物种的生物膜上形成了双物种生物膜，其中肠炎沙门氏菌和革兰氏阳性菌同时存在，并通过共聚焦激光扫描显微镜（CLSM）进行了评估。所有菌株都能够形成生物膜。在观察场为 14161μm 的情况下，72 小时后观察到单物种生物膜的最大生物体积，其中生物体积为 94409.0μm±2131.0μm（肠炎沙门氏菌）、58418.3μm±5944.9μm（单核细胞增生李斯特菌）、68020.8μm±5812.3μm（MRSA）和 59280.0μm±4032.9μm（VRE）。与单物种生物膜相比，在 48、72 和 120 小时时，MRSA 或 VRE 存在时，肠炎沙门氏菌的生物体积更高。在双物种生物膜中，细菌呈现双层分布模式，上层为肠炎沙门氏菌，下层为革兰氏阳性菌。在开发有效消除生物膜的策略时，应考虑这种空间配置。
