Fig. 2 Comparison of biosurfactants and broad-spectrum antibiotics on established single-species biofilms. Aliquots (10 ll) of rhamnolipids (Rh), a plant biosurfactant (PB) (total 20 lg), ampicillin (AMP), chloramphenicol (CHL) and kanamycin (KAN) (total 5 lg) were added apically to homogenous bacterial biofilms that had been cultivated for 2 days. The biofilms were a B. subtilis, b M. luteus and c S. aureus. After a further 2 days of incubation, the biofilms were quantified using the crystal violet adhesion assay. Quantification of biofilm biomass was in comparison to the control biofilm (B) which consisted of BSA ? bacteria. Biofilm dispersal values were annotated as mean ± SEM, n = 4–12. A two-tailed students t test was used to determine if test biofilms significantly differed from the control biofilm of the same species (*P \ 0.05, **P \ 0.01, ***P \ 0.001)
...read more