Research Article

Inhibitory Effects of Chrysanthemum boreale Essential Oil on Biofilm Formation and Virulence Factor Expression of Streptococcus mutans

Figure 4

Effect of Chrysanthemum boreale (C. boreale) essential oil on biofilm formation on polystyrene dishes by Streptococcus mutans (S. mutans). S. mutans was inoculated into BHI broth with various concentrations of C. boreale essential oil and cultured for 48 h. The biofilm that formed on the polystyrene dish surface was measured by staining with 0.1% safranin. Biofilm formation was also significantly inhibited at 0.1 mg/mL and 0.5 mg/mL of the C. boreale essential oil. 0.1% of sodium fluoride (NaF) was used as a positive control.