Sodium houttuyfonate in vitro inhibits biofilm dispersion and expression of bdlA in Pseudomonas aeruginosa

Biofilm dispersion is the last step in the development of biofilms, and allows bacteria to spawn novel biofilms in new locales. In the previous studies, we found that sodium houttuyfonate (SH) is effective at inhibiting biofilm formation and motility of Pseudomonas aeruginosa. Here, we investigated the effect of SH against the biofilm dispersion of P. aeruginosa by an in vitro model. The results show that the plant derivative, SH, could effectively inhibit both biofilm dispersion of P. aeruginosa, and gene and protein expression of the key biofilm regulator BdlA in a dose-dependent manner. Furthermore, our presented results suggest that SH can penetrate into the biofilm of P. aeruginosa to repress the biofilm life cycle. Therefore, these results indicate that the antimicrobial activity of SH may be partially due to its ability to disrupt biofilm dispersion in P. aeruginosa.