The effect of heavy metals on thiocyanate biodegradation by an autotrophic microbial consortium enriched from mine tailings

Abstract

Bioremediation systems represent an environmentally sustainable approach to degrading industrially-generated thiocyanate (SCN - ), with low energy demand and operational costs, and high efficiency and substrate specificity. However, heavy metals present in mine tailings effluent may hamper process efficiency by poisoning thiocyanate-degrading microbial consortia. Here we experimentally tested the tolerance of an autotrophic SCN - -degrading bacterial consortium enriched from gold mine tailings for Zn, Cu, Ni, Cr, and As. All of the selected metals inhibited SCN - biodegradation to different extents, depending on concentration. At pH of 7.8 and 30°C, complete inhibition of SCN - biodegradatio..