Synergy and Mode of Action of Ceftazidime plus Quercetin or Luteolin on Streptococcus pyogenes

Figure 2

The effect of ceftazidime, luteolin, and quercetin either alone or in combination on the viable counts of S. pyogenes DMST 30653. Con = control (drugs free); Lut (64) = 64 μg mL⁻¹ luteolin; Que (64) = 64 μg mL⁻¹ quercetin; Cef (0.25) = 0.25 μg mL⁻¹ ceftazidime; Cef (0.12) + Lut (16) = ceftazidime 0.12 μg mL⁻¹ plus luteolin 16 μg mL⁻¹; Cef (0.12) + Que (4) = ceftazidime 0.12 μg mL⁻¹ plus quercetin 4 μg mL⁻¹. The experiment was performed in four observations and all graphs are shown as mean ± SEM.