Abstract
Mossbauer investigations of iron minerals formed during the process of synthesized ferrihydrite (SF) reduction by anaerobic alkaliphilic bacterium Geoalkalibacter ferrihydriticus and anaerobic thermophilic bacterium Thermincola ferriacetica were carried out involving magnetization measurements. The influence of T. ferriacetica and G. ferrihydriticus growth media on SF was investigated.
It was found that SF after its interaction with the mineral media was almost identical. There were also analyzed minerals that formed during the growth of binary culture of Geoalkalibacter ferrihydriticus and Anaerobacillus alkalilacustris at the concentrations of SF equal to 10mM.
The new phase formed under this concentration is probably of FeII-FeIII (oxy-)hydroxycarbonate nature. Mossbauer spectroscopy showed that in all experiments where magnetically ordered phases formed by dissimilatory iron-reducing bacteria, a mixture of nonstoichiometric magnetite (Fe3O4) and maghemite (gamma-Fe2O3) was observed.