The most significant environmental issue that has arisen in the mining industries over the last two decades is that of Acid Mine Drainage or Acid Rock Drainage (AMD/ARD) from tailing dumps and waste mined rock piles. Bacillus subtilis and its metabolic products have been used in our studies. In this work, selective sepn. of pyrite from oxides such as quartz and calcite as well as galena (sulfide mineral) was achieved. Through microbially induced flotation, pyrite could be sepd. with 90% efficiency from quartz and calcite leading to desulphurisation and depyritization making the process environmentally benign. Mineral specific proteins were found in extracellular proteins isolated from the cell free ext. when B. subtilis was grown in presence of minerals through SDS-PAGE. The suppression of some genes was obsd. in the RAPD profile of the genomic DNA in presence of minerals. The cells of B. subtilis proved to be 45-60% efficient in the biosorption of lead metal ions at 10 and 50ppm of lead metal ion. The exopolymers extd. from B. subtilis proved to be 50-60% efficient in biosorption of lead metal ions. This study shows possibilities for development of eco friendly technologies for bioremediation
