Introduction of metallic pollutant (Fi , Ni) reducing bacteria in Musa Bay

In order to isolate bacterial strains resistant to iron and nickel, deposit samples were collected from five stations in Musa Bay and cultured on BHI agar medium containing 1000 ppm of iron and 50 ppm of nickel. Endurance threshold of strains isolated to different concentrations of iron (1000- 15000 ppm) and nickel (100- 25000 ppm) in BHI broth medium were evaluated, the most resistant strains were selected and MIC and MBC were determined. Results of the current study demonstrated that among 16 and 12 resistant strains to nickel and iron, two selected strains (Bacillus subtilis and Micrococcus sp. ) as the most resistant strains had MIC and MBC (29700 and 29800 ppm) and (26300 and 26500 ppm ), respectively, Iron’s MIC was not assessed. Results of atomic absorption analysis demonstrated that the highest amount of nickel reduction in a medium with concentration of 194 ppm and 71 ppm were 16.7% and 63% after 72 hours by selected strain of Bacillus subtilis respectively, and in a medium containing 158 ppm iron, after 50 hours 8.4% by selected strain 7, while dead biomass of strain 16 reduced nickel to the amount of 40.6% and it reduced 21% and 4% of iron in solutions with 46 ppm and 792 ppm of iron. Results of molecular analysis demonstrated that strain 16 was Bacillus subtilis. In addition, Bacillus subtilis being isolated in this study with ability of nickel and iron removal is an appropriate candidate to be used in aquatic environments