Isolation and characterization of three siderophores from marine bacteria

One new siderophore (3) along with the previously reported nocardamine (1) and schizokinen A (2) were isolated from the culture broth of three bacteria isolated from unidentified marine sponges. The minimal active concentrations of the compounds by chrome azurol S (CAS) liquid assay are 5, 4 and 156 mu g/mL, respectively.