Biologically-induced precipitation of minerals in a medium with zinc under sulfate-reducing conditions

Abstract

A b s t r a c tSulfate-reducing microbial communities were enriched from soils collected in areas with crude-oil exploitation. Cultures were grown in modified Postgate C medium and minimal medium, with ethanol or lactate as an electron donor. The batch cultures were grown with addition of zinc in concentrations of 100-700 mg/l. A lack of increased protein concentration in the solutions compared with the control batch, was noted in cultures containing over 200 mg Zn 2+ /l. The 16S rRNA method was applied to determine the specific composition of the selected microorganism communities. The analysis indicated the presence of Desulfovibrio spp., Desulfobulbus spp. and Desulfotomaculum spp. in the communities. Diffractometric analysis indicated the presence of biogenic sphalerite in cultures with 100 and 200 mg Zn 2+ /l and elemental sulfur in cultures with 200 mg Zn 2+ /l. Other post culture sediments (300−700 mg Zn 2+ /l) contained only hopeite [Zn 3 (PO 4 ) 2 . 4H 2 O] formed abiotically during the experiment, which was confirmed by studies of the activity of sulfate-reducing microbial communities. K e y w o r d s: biogenic precipitation, biomineralization, 16S rRNA, sulfate-reducing bacteria, zinc

Potential of Autochthonous Sulfate-Reducing Microbial Communities for Treating Acid Mine Drainage in a Bench-Scale Sulfidogenic Reactor

“…Sahinkaya and Yucesoy (2010) also found that substituting lactate with ethanol as a substrate in sulfidogenic reactors did not affect the sulfate removal efficiencies or system performance. Wolicka et al (2015) obtained lower sulfate removals than those observed in this study (~25% and 30% for lactate and ethanol, respectively, as carbon sources) when SRB communities enriched on a modified Postgate C medium were used as inoculum in the Figure 5. (a) Sulfate-reducing bacteria community profiles of the LAC, FOR, and ETA reactors under indicated initial pH conditions were compared using DGGE analysis.…”

Microbial Diversity of Bacteria Involved in Biomineralization Processes in Mine-Impacted Freshwaters

“…In order to test the optimal conditions for growth and metal bio-precipitation, the enrichment cultures from each sediment were transferred to fresh standard “Postgate B” liquid medium (indicated with the number “1”) and to its modified versions (“2” and “3”) supplemented with Zn and Fe sulfate at different concentrations, as described in Table 1 and Figure 2 . In media 2 and 3, Zn was added to allow SRB growth and activity, according to literature data ( Azabou et al, 2007 ; Wolicka et al, 2015 ). In the same media, the amount of Fe was reduced to favor Zn precipitation and to make it more visible: in medium 2, FeSO 4 was added in the concentration suggested by Wolicka et al (2015) in their Zn bio-precipitation experiments, and in medium 3 it was further reduced to the minimum concentration used for the preparation of other sulfate reducer culture media, as reported by Atlas (2005) .…”

“…In media 2 and 3, Zn was added to allow SRB growth and activity, according to literature data ( Azabou et al, 2007 ; Wolicka et al, 2015 ). In the same media, the amount of Fe was reduced to favor Zn precipitation and to make it more visible: in medium 2, FeSO 4 was added in the concentration suggested by Wolicka et al (2015) in their Zn bio-precipitation experiments, and in medium 3 it was further reduced to the minimum concentration used for the preparation of other sulfate reducer culture media, as reported by Atlas (2005) . For each different medium, the enrichment was repeated at least four times.…”