?INFLUENCE OF NUTRIENTS ON THE BIOLOGICAL OXIDATIVE ACTIVITIES OF ALOCALLY ISOLATED THIOBACILLUS FERROOXlDAN

Abstract

The strain of Thiobacillusferrooxidan was isolated from the Sorange coal mine water in ferrous sulphate medium. The
effects of inorganic nitrogen (NH4+' NO)-) and phosphate on the biological oxidation of copper sulphide ore were
examined. It is observed that the iron was solubilized first from FeS2 or Fet • x S to as Fe'" and then oxidized to Fe"'", The
dissolution of iron Fe'" was a chemical reaction whereas the conversion of Fe'" to Fe"'" was bacteria mediated. The
addition and increase in the concentration of phosphate delayed and reduced the conversion of Fe'" to Fe"'". Ammonium
was found to be the preferred source of nitrogen for the isolated bacterium. The nitrogen as NH/ increased the Fe'"
oxidation whereas NO)· had negative effect. The solubilization of copper was directly related to the Fe'" iron oxidation.
Maximum dissolved copper concentration were observed in 6mM ammonium supplemented medium and minimum in
6mM nitrate.