Abstract：
In the food industry, successful bacterial pathogen colonization and persistence begin with their adhesion to a surface, followed by the spatial development of mature biofilm of public health concerns. Compromising bacterial settlement with natural inhibitors is a promising alternative to conventional anti-fouling treatments typically based on chemical biocides that contribute to the growing burden of antimicrobial resistance. In this study, three extracellular polymeric substance (EPS) fractions extracted from microalgae biofilms of Cylindrotheca closterium (fraction C) and Tetraselmis suecica (fraction Ta rich in insoluble scale structure and fraction Tb rich in soluble EPS) were screened for their anti-adhesive properties, against eight human food-borne pathogens belonging to Escherichia coli, Staphylococcus aureus, Salmonella enterica subsp. enterica, and Listeria monocytogenes species. The results showed that the fraction Ta was the most effective inducing statistically significant reduction for three strains of E. coli, S. aureus, and L. monocytogenes. Overall, EPSs coating on polystyrene surfaces of the different fractions increased the hydrophilic character of the support. Differences in bacterial adhesion on the different coated surfaces could be explained by several dissimilarities in the structural and physicochemical EPS compositions, according to HPLC and ATR-FTIR analysis. Interestingly, while fractions Ta and Tb were extracted from the same microalgal culture, distinct adhesion patterns were observed, highlighting the importance of the extraction process. Overall, the findings showed that EPS extracted from microalgal photosynthetic biofilms can exhibit anti-adhesive effects against food-borne pathogens and could help develop sustainable and non-toxic anti-adhesive surfaces for the food industry. KEY POINTS: •EPSs from a biofilm-based culture of C. closterium/T. suecica were characterized. •Microalgal EPS extracted from T. suecica biofilms showed bacterial anti-adhesive effects. •The anti-adhesive effect is strain-specific and affects both Gram - and Gram + bacteria.
摘要：
在食品工业中,成功的细菌病原体定植和持久性始于它们对表面的粘附，其次是公共健康关注的成熟生物膜的空间发展。具有天然抑制剂的妥协细菌沉降是典型地基于化学杀生物剂的常规防污处理的有希望的替代方案,所述化学杀生物剂有助于抗微生物剂抗性的增加的负担。在这项研究中,筛选了从Clidrothecaclosterium（C级）和Tetraselmissuecica（富含不溶性鳞片结构的Ta级和富含可溶性EPS的Tb级）的微藻生物膜中提取的三种胞外聚合物（EPS）级分的抗粘附性能，针对八种属于大肠杆菌的人类食源性病原体，金黄色葡萄球菌,肠沙门氏菌亚种。enterica,和单核细胞增生李斯特菌。结果表明，对于三种大肠杆菌菌株，Ta是最有效的诱导统计学上显著的减少，金黄色葡萄球菌，和L.单核细胞增生。总的来说,在不同级分的聚苯乙烯表面上涂覆的EPS增加了载体的亲水性。不同涂层表面上细菌粘附的差异可以通过结构和物理化学EPS组成的几种差异来解释。根据HPLC和ATR-FTIR分析。有趣的是,虽然从相同的微藻培养物中提取级分Ta和Tb，观察到不同的粘连模式，强调提取过程的重要性。总的来说,研究结果表明，从微藻光合生物膜中提取的EPS可以对食源性病原体表现出抗粘附作用，并有助于为食品工业开发可持续且无毒的抗粘附表面。关键词：•EPS来自基于生物膜的C.closterium/T.培养物Suecica被表征。•从头藻生物膜中提取的微藻EPS显示出细菌抗粘附作用。•抗粘附作用是菌株特异性的并且影响革兰氏-和革兰氏+细菌。
