Growth curves of <i>S</i>. <i>aureus</i> at sub-inhibitory concentrations of baicalein.

<p>Baicalein at 16, 32 and 64 μg/mL had no effect on bacterial growth.</p

Relative expression of the <i>ica</i>(using 16S rRNA / <i>gyrA</i> / <i>gmk</i> as the internal parametric gene).

<p>Comparative measurement of relative expression shown as an average of 3 experiments (★ compared to the control group, P < 0.05).</p

Relative expression of the <i>agrA</i> (using 16S rRNA / <i>gyrA</i> / <i>gmk</i> as the internal parametric gene).

<p>Comparative measurement of the relative expression shown as average of 3 experiments. (★ compared to the control group, P < 0.05).</p

Relative expression of the <i>sarA</i> (using 16S rRNA / <i>gyrA</i> / <i>gmk</i> as the internal parametric gene).

<p>Comparative measurement of relative expression shown as an average of 3 experiments (★ compared to the control group, P < 0.05).</p

SEA detected by western blot.

<p>Upper: Western blot analysis of SEA from control group and groups treated with 64, 32, and 16 μg/ml baicalein for 5 h. Lower: Band intensities were quantitated by densitometry. Each lane was divided by the logarithmic number of cells in order to evaluate the amount of SEA per cell. (<b>*</b> P < 0.05, compared to the control group with one-way ANOVA). Data shown are the average of 3 experiments.</p

Impact of baicalein as assessed by fluorescence microscopy(200×).

<p>Static biofilms after exposure to baicalein for 3 days (top) and 7 days (bottom) were assessed by SYTO9. <i>S</i>. <i>aureus</i> within biofilms on polystyrene slices diplay green fluorescence. Controls group (A, E); 16 μg/ml baicalein group(B, F); 32 μg/ml baicalein group (C,G); 64 μg/ml baicalein group (D,H) A, E: control group; B, F: 16 μg/mL baicalein group; C, G: 32 μg/mL baicalein group; D, H: 64 μg/mL baicalein group.</p

Relative expression of the <i>hla</i> (using 16sRNA as the internal parametric gene).

<p>Comparative measurement of the relative expression shown as average of 3 experiments. (★ compared to the control group, P < 0.001).</p

Inhibition of biofilm formation in clinical <i>S</i>. <i>aureus</i> strains by baicalein.

<p>The biofilms were stained with crystal violet and detected by OD₅₉₅ (shown as the average of 3 experiments).</p

Relative expression of the RNAIII (using 16S rRNA / <i>gyrA</i> / <i>gmk</i> as the internal parametric gene).

<p>Comparative measurement of relative expression shown as an average of 3 experiments (★ compared to the control group, P < 0.05).</p

Baicalein Inhibits <i>Staphylococcus aureus</i> Biofilm Formation and the Quorum Sensing System <i>In Vitro</i> - Fig 5

<p><b>(a) Use of baicalein as adjunct therapy with conventional antibiotics for 3-day biofilms.</b> Biofilms were formed on polystyrene carriers for 3 days by growing of <i>S</i>. <i>aureus</i> in TSB-G, then treating with VCM alone or combination with baicalein or CLR for 12 h (* compared to the control group, P < 0.001; # compared to the CLR+VCM group, P < 0.05; average of 3 experiments). <b>(b) Three-day biofilm scanning by SEM (×15000)</b> A: control group; B: 4 μg/mL VCM; C: 16 μg/mL CLR; D: 16 μg/mL CLR + 4 μg/mL VCM; E: 32 μg/mL baicalein; F: 32 μg/mL baicalein + 4 μg/mL VCM. <b>(c) Three-day biofilm scanning by CLSM (×400)</b> A: control group; B: 4 μg/mL VCM C: 32 μg/mL baicalein; D: 32 μg/mL baicalein + 4 μg/mL VCM.</p