The binding of H2O2-generated Fe(III) to Bifidobacterium thermophilum depends on the method of its production

Fe(OH)(3) was produced from Fe(II) and H2O2 by methods associated with high and low free radical activity. More Fe(OH)(3) became bound to Bifidobacter ium thermophilum when the former type of method was used, and protoplasting experiments indicated that binding to both the cell walls and membranes wa s enhanced. Binding to cell walls was instantaneous, whilst that by the mem branes increased with time using both methods. Al(III), a lipid peroxidatio n enhancer, increased Fe(OH) binding by membranes only. It was concluded th at B. thermophilum is able to abate increased activity of free radicals not only by scavenging them, but also by removing iron from their environment.