Pudilan Keyanning mouthwash inhibits dextran-dependent aggregation and biofilm organization of Streptococcus mutans

Aims: This research aimed to investigate the inhibitory effects of Pudilan mouthwash (PDL) on Streptococcus mutans (S. mutans) biofilms and identify its chemical components. Methods and results: The impacts of 100% concentrated PDL on S. mutans biofilm were detected by colony-forming unit (CFU) assays, crystal violet staining, confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM), and quantitative real-Time PCR (qRT-PCR). The biocompatibility with human gingival fibroblasts (HGFs) was evaluated by Cell-Counting-Kit-8 (CCK-8) assay. And chemical components were identified by UPLC-HRMS. PBS and 0.12% chlorhexidine were used as negative and positive controls, respectively. Results indicate early 8-h S. mutans biofilms are sensitive to PDL. Additionally, it leads to a decrease in bacterial activities and dextran-dependent aggregation in 24-h S. mutans biofilms. PDL significantly downregulates the gene expression of gtfB/C/D and smc. And 114 components are identified. Conclusions: PDL has an inhibitory effect on S. mutans and favorable biocompatibility. It has potential to be exploited as a novel anti-biofilm agent.