Comparison of five bacterial strains producing siderophores with ability to chelate iron under alkaline conditions

AMB Express

Table 2 Summary of the main properties of the bacteria studied

Bacteria	Average complexation capacity at pH 9.0 (µmol L⁻¹)	Siderophore type^a	Growth and handling^b
Azotobacter vinelandii	188	C+H	+++
Bacillus megaterium	280	H	+++
Bacillus subtilis	225	C	+
Pantoea allii	Weak	H	+
Rhizobium radiobacter	Weak	C	+

^aSiderophore type: C = catecholate; H = hydroxamate
^bGrowth and handling: it was considered the growth rate of the bacteria, culture media composition and easiness of the bacterial removal by centrifugation/filtration