Table 3.

Concentration of iron ligands in GMO4-14, GMO4-16, GMO4-18 culture supernatant extracts.

	Mean siderophore content (SDα) as detected by
Strain	Supplement compound in	Csaky test	Arnow reaction
	liquid IDSM medium
GMO4-11	DEF+3OC6-HSL	ND	0.14(0.01)
GMO4-14	DEF+3OC6-HSL	ND	0.08 (0.02)
GMO4-16	DEF+C8-HSL	ND	ND
GMO4-18	DEF+C8-HSL	ND	ND

SDα values are given as micromoles of ligand per gram (dry weight) of cells and represent the mean of three experiments. ND, not detected (i.e., the concentration was below the detection limit of the assay.)