Figure 4. Inhibitory effect of prenylated flavonoids on growth and biofilm formation of P. gingivalis.

(A–C) P. gingivalis growth in the presence of prenylated flavonoids at 12.5 µM is shown by measuring absorbance at 620 nm different time points. Results were similar in each of three independent experiments and representative data are shown as means ± SD in a triplicate assay. (D) Biofilm formation (absorbance at 492 nm after staining with safranin) was assessed after a 24 h-culture in the presence of a compound at 1.25 µM. All the compounds at 1.25 M had no effect on growth of P. gingivalis. Results were similar in three independent experiments and representative data are shown. Results are expressed as means ± SD in a triplicate assay. Data were statistically analyzed by one-way analysis of variance (ANOVA) followed by the Dunnett’s multiple comparison test. Asterisks indicate significant difference (P < 0.05) from values obtained in the absence of flavonoids.