Streptococcus mutans is the principal biofilm forming oral pathogen associated with dental caries. Studies have shown that Candida albicans, a commensal oral fungus is capable of forming pathogenic mixed-species biofilms with S. mutans. The treatment of bacterial and fungal infections using conventional antimicrobial agents has become challenging due to the antimicrobial resistance of the biofilm mode of growth. The present study aimed to evaluate the efficacy of secretory components of Lactobacillus plantarum 108, a potentially promising probiotic strain, against S. mutans and C. albicans single and mixed-species biofilms. L. plantarum 108 supernatant inhibited S. mutans and C. albicans single-species biofilms as shown by XTT reduction assay, crystal violet assay, and colony forming units counting. The probiotic supernatant significantly inhibited the S. mutans and C. albicans mixed-species biofilm formation. The pre-formed mixed-species biofilms were also successfully reduced. Confocal microscopy showed poorly developed biofilm architecture in the probiotic supernatant treated biofilms. Moreover, the expression of S. mutans genes associated with glucosyltransferase activity and C. albicans hyphal specific genes (HWP1, ALS1 and ALS3) were down-regulated in the presence of the probiotic supernatant. Altogether, the data demonstrated the capacity of L. plantarum 108 supernatant to inhibit the S. mutans and C. albicans mixed-species biofilms. Herein, we provide a new insight on the potential of probiotic-based strategies to prevent bacterial-fungal mixed-species biofilms associated with dental caries.

中文翻译：

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植物乳杆菌108抑制变形链球菌和白色念珠菌混合物种生物膜形成。

变形链球菌是形成与龋齿相关的口腔病原体的主要生物膜。有研究表明，白色念珠菌，共生真菌口服能够形成与致病混合物种的生物膜S.变形链球菌。由于生物膜生长方式的抗微生物性，使用常规抗微生物剂治疗细菌和真菌感染已变得具有挑战性。本研究的目的是评估的分泌成分的功效植物乳杆菌108，一个潜在的有前途的益生菌菌株，针对S.变形链球菌和白色念珠菌单一和混合物种的生物膜。植物乳杆菌108的上清液抑制S.变形链球菌和白色念珠菌单一物种的生物膜如图XTT还原测定，结晶紫测定，和菌落形成单位计数。益生菌上清液显著抑制S.变形链球菌和白色念珠菌混合物种的生物膜形成。预先形成的混合物种生物膜也被成功还原。共聚焦显微镜显示在益生菌上清液处理过的生物膜中生物膜结构欠发达。此外，表达S.变形链球菌 基因的葡萄糖基转移酶活和相关联的白色念珠菌菌丝特异性基因（HWP1，ALS1和ALS3）在益生菌上清液的存在下被下调。总之，数据显示的容量植物乳杆菌108的上清液抑制S.变形链球菌 和白色念珠菌混合物种的生物膜。本文中，我们提供了基于益生菌的策略来预防与龋齿相关的细菌-真菌混合物种生物膜的潜力的新见解。