FIGURE 4.

Effects of iron (40 μM Fe²⁺ and 20 μM Fe³⁺) on biofilm formation in 70 chicken isolates of C. jejuni that inherently form biofilms at low (A), medium (B), and high (C) levels. The inherent capability of biofilm formation was determined based on the OD₅₉₅ in the biofilm assay. The low-, medium-, and high-level biofilm formers were those that generated OD₅₉₅ of less than 0.3, between 0.3 and 0.5, and greater than 0.5, respectively, in the absence of iron. The results show the means and standard deviations of three samples in a single experiment. The experiments were repeated three times, and similar results were observed in all repeated experiments. The statistical analysis was performed with Student’s t-test compared to the control without iron treatment. ^∗P < 0.05.