Figure 3. The effects of ebselen and antibiotics (linezolid, mupirocin, vancomycin and rifampicin) on established biofilms of S. aureus (a) or S. epidermidis(b).
The established biofilms were treated with control antibiotics or ebselen and stained with crystal violet. Optical density of dissolved crystal violet was measured using a spectrophotometer. Values are the mean of triplicate samples with the standard deviation bars. P values of (*,#P ≤ 0.05) are considered as significant. Ebselen was compared to controls (*) and to antibiotics (#). Detailed P values are listed: S. aureus (a): Control vs linezolid, 0.0214; Control vs mupirocin, 0.0001; Control vs vancomycin, 0.004; Control vs rifampicin, 0.0001; Control vs ebselen, 0.0001; linezolid vs ebselen, 0.0014; mupirocin vs ebselen, 0.0004; vancomycin vs ebselen, 0.003; rifampicin vs ebselen, 0.0047. S. epidermidis (b): Control vs linezolid, 0.0036; Control vs mupirocin, 0.0008; Control vs vancomycin, 0.0011; Control vs rifampicin, 0.0004; Control vs ebselen, 0.0004; linezolid vs ebselen, 0.0033; mupirocin vs ebselen, 0.0052; vancomycin vs ebselen, 0.0040; rifampicin vs ebselen, n.s (not significant).