Top Institute Food and Nutrition (TIFN), Nieuwe Kanaal 9A, 6709 PA Wageningen, The Netherlands; Laboratory of Food Microbiology, Wageningen University and Research Centre, Bornse Weilanden 9, 6700 AA Wageningen, The Netherlands.
Top Institute Food and Nutrition (TIFN), Nieuwe Kanaal 9A, 6709 PA Wageningen, The Netherlands; Laboratory of Food Microbiology, Wageningen University and Research Centre, Bornse Weilanden 9, 6700 AA Wageningen, The Netherlands.
Int J Food Microbiol. 2015 Aug 17;207:23-9. doi: 10.1016/j.ijfoodmicro.2015.04.030. Epub 2015 Apr 24.
Lactobacillus plantarum has been associated with food spoilage in a wide range of products and the biofilm growth mode has been implicated as a possible source of contamination. In this study we analysed the biofilm forming capacity of L. plantarum WCFS1 and six food spoilage isolates. Biofilm formation as quantified by crystal violet staining and colony forming units was largely affected by the medium composition, growth temperature and maturation time and by strain specific features. All strains showed highest biofilm formation in Brain Heart Infusion medium supplemented with manganese and glucose. For L. plantarum biofilms the crystal violet (CV) assay, that is routinely used to quantify total biofilm formation, correlates poorly with the number of culturable cells in the biofilm. This can in part be explained by cell death and lysis resulting in CV stainable material, conceivably extracellular DNA (eDNA), contributing to the extracellular matrix. The strain to strain variation may in part be explained by differences in levels of eDNA, likely as result of differences in lysis behaviour. In line with this, biofilms of all strains tested, except for one spoilage isolate, were sensitive to DNase treatment. In addition, biofilms were highly sensitive to treatment with Proteinase K suggesting a role for proteins and/or proteinaceous material in surface colonisation. This study shows the impact of a range of environmental factors and enzyme treatments on biofilm formation capacity for selected L. plantarum isolates associated with food spoilage, and may provide clues for disinfection strategies in food industry.
植物乳杆菌与广泛的产品食品腐败有关，生物膜生长模式被认为是污染的可能来源。在这项研究中，我们分析了植物乳杆菌 WCFS1 和六种食品腐败分离株的生物膜形成能力。通过结晶紫染色和菌落形成单位定量的生物膜形成在很大程度上受到培养基组成、生长温度和成熟时间以及菌株特异性特征的影响。所有菌株在补充锰和葡萄糖的脑心浸液培养基中表现出最高的生物膜形成能力。对于植物乳杆菌生物膜，结晶紫（CV）测定法通常用于定量总生物膜形成，与生物膜中可培养细胞的数量相关性较差。这部分可以通过细胞死亡和裂解导致 CV 可染色物质（可能是细胞外 DNA[eDNA]）的形成来解释，这些物质可能构成细胞外基质。菌株间的变异部分可以用 eDNA 水平的差异来解释，可能是由于裂解行为的差异造成的。与此一致的是，除了一种腐败分离株外，所有测试菌株的生物膜都对 DNase 处理敏感。此外，生物膜对蛋白酶 K 的处理高度敏感，这表明蛋白质和/或蛋白质物质在表面定植中起作用。本研究表明了一系列环境因素和酶处理对与食品腐败有关的选定植物乳杆菌分离株生物膜形成能力的影响，并为食品工业中的消毒策略提供了线索。
