Figure 1

Antibiofilm activities of alizarin against S. aureus and S. epidermidis.
The antibiofilm activities (OD570) of alizarin were determined against two methicillin-sensitive S. aureus strains (MSSA, ATCC 25923 and ATCC 6538), a methicillin-resistant S. aureus strain (MRSA, MW2) (a–c) and S. epidermidis (ATCC 14990) (d). Two independent experiments were conducted (12 wells per sample); error bars indicate standard deviations. *P < 0.05 versus non-treated controls (N or None). Biofilm formation on glass was observed by confocal laser microscopy (e). Scale bars represent 50 μm.