Figure 5.

The comparison of the biofilm formation between the wild types and derivatives (amoxicillin-induced) of E. coli strains No. 5 and No. 6. Each bar represents the mean with standard deviation based on the OD value of the absorbed crystal violet (0,3%) measured at 531 nm (A₅₃₁) for each strain from particular groups (wild types and derivatives). The study was performed in four replications in two independent experiments. The difference is significant (p < 0.05, unpaired T-test, two-tailed, nonparametric).