Abstract
The present article provides information on the application of biotechnology in the valorization of mineral resources. Biohydrometallurgy is relatively a recent development but already employed in the copper, uranium and in a limited extent in precious metal processing industries. The basic principles of bioleaching and the mechanisms of bacterial action are discussed and specific examples are given for the biohydrometallurgy of the elements. An extended treatment of microbial activity is given with regard to gold and silver recoveries from ores and leach solutions, as well as for the desulfurization of coal, to represent tendencies of most active research areas. The article discusses also the biosorption processes and gives a short review of efforts devoted to biogenetic engineering of leaching organisms.