Potential impact of microbial consortia in biomining and bioleaching of commercial metals

Biomining is the use of microorganisms for the commercial extraction of lavish metals from ores and mines with least effect on environment. Microbes play vital role in bioleaching procedures in commercial mining. The bacterial cells are used to detoxify/replace waste cyanide, marginal biomass and activated carbon. These methods are preferred over conventional techniques due to energy efficient, low cost, environment friendly and production of useful by-products. At industrial scale, different microbial strains (Acidophilic, Sulphobacillus, Rhodococcus, Ferrimicrobium &chemolithotrophic) are deployed to boost the processes of copper and uranium bioleaching. About 20% of the world’s copper is extracted by using this technique. These extraction procedures involve oxidation of insoluble metal sulphides to soluble sulphates. The isolation of thermophilic microbes for mineral biooxidation increase the commercial extraction of minerals at industrial scale. The conventional pyrometallurgical techniques have environmental concerns as they result in depletion of high grade ores and release harmful gaseous. The microbe-assisted gold mining is expected to double the yield of gold and needs to be fully explored using diverse array of microbes. Bioleaching is simple and low cost method for the developing countries with large ore deposits. About 30 strains of microbes have been discovered so for with potential impact on bioleaching. With advances in molecular genetics, physiology and microbial genomics, more promising strains with increased bioactivities are possible. Further efforts are underway to culture diverse range of archaea and improving its genetic potential to be used as industrial tool for commercial bioleaching. The currents review enlightens the recent trends in biomining/bioleaching and implementation of modern biological approaches to engineer target microbes for commercial use