title: Characterization and activity studies of highly heavy metal resistant sulphate-reducing bacteria to be used in acid mine drainage decontamination.
abstract: Biological treatment with sulphate-reducing bacteria (SRB) has been considered as the most promising alternative for acid mine drainage (AMD) decontamination. Normally, these wastewaters contain high concentrations of sulphate and heavy metals, so the search for SRB highly resistant to metals is extremely important for the development of a bioremediation technology. A SRB consortium resistant to high concentrations of heavy metals (Fe, Cu and Zn), similar to those typically present in AMD, was obtained among several environmental samples, from a wastewater treatment plant. The phylogenetic analysis of the dsr gene sequence revealed that this consortium contains species of SRB affiliated to Desulfovibrio desulfuricans and Desulfobulbus rhabdoformis. The results show that the presence of usually lethal concentrations of Fe (400mg/L), Zn (150 mg/L) and Cu (80 mg/L) is not toxic for the sulphate-reducing bacteria present in this sample. As a consequence, a very good efficiency in terms of sulphate reduction and metals removal was obtained. Both ethanol and lactate can be used by this inoculum as carbon source. With the other samples tested sulphate reduction was inhibited by the presence of copper and zinc. This highly metal resistant consortium will be used to inoculate a bioreactor to carry out AMD decontamination.
authors.affiliation: Centro de Ciências do Mar, CCMAR, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal.
authors.forename: Mónica
authors.initials: M
authors.lastname: Martins
authors.forename: M Leonor
authors.initials: ML
authors.lastname: Faleiro
authors.forename: Raúl J
authors.initials: RJ
authors.lastname: Barros
authors.forename: A Raquel
authors.initials: AR
authors.lastname: Veríssimo
authors.forename: M Alexandra
authors.initials: MA
authors.lastname: Barreiros
authors.forename: M Clara
authors.initials: MC
authors.lastname: Costa
mesh_terms: D000143:Acids; D001673:Biodegradation, Environmental; D000431:Ethanol / Q000378:metabolism; D007220:Industrial Waste / Q000517:prevention & control*; D019344:Lactic Acid / Q000378:metabolism; D019216:Metals, Heavy; D008906:Mining / Q000379:methods; D013431:Sulfates / Q000378:metabolism; D016999:Sulfur-Reducing Bacteria / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000378:metabolism
chemical_list: D000143:Acids; D007220:Industrial Waste; D019216:Metals, Heavy; D013431:Sulfates; D014874:Water Pollutants, Chemical; D019344:Lactic Acid; D000431:Ethanol