Effect of siderophores against E. coli O157:H7

In this study, the inhibiting activity of siderophores produced by Pseudomonas fluorescens against Escherichia coli O157:7 was assayed. Siderophores were extracted from P. fluorescens cultures and preliminarily tested by C.A.S. reagent and UV. The siderophores activity against E. coli O157:H7 was characterised by the determination of Minimal Inhibiting Concentration (MIC). Furthermore, E. coli O157:H7 growth tests with and without siderophores were prepared at 12°C, pH 7 and 5, aw 0.997 and 0,988. The MIC was assessed at 7 μg/ml whereas the growth test showed a high inhibiting activity with the exception of tests at pH 5.