Figure 3

Antibacterial activity of essential oils in zone of clearance assays. Graph showing mean halo diameters +/- SEM obtained from four separate zone of clearance assays to determine the ability of plant essential oils to lyse E. coli. Significance levels obtained from two-tailed t tests are denoted by stars: * = Significant, P < 0.05; ** = highly significant, P < 0.01; *** = very highly significant, P < 0.001.