Biodegradation of Chromium Contaminated Soil by Some Bacterial Species

Chromium (Cr) is one of the most common heavy metals affecting the soil quality which is introduced into the environment from industries such as leather tanning, electroplating and inorganic pigment (green, orange and yellow) production. The leather industry is the major source for the environmental influx of Cr. Cleaning up of the Cr contaminated sites is a challenging task. Bioremediation is an emerging area that could be considered for the remediation of contaminated sites because of its cost effectiveness and aesthetic advantages. Microbial degradation of heavy metals is one of the major practices in natural decontamination process. In the present study heavy metals degradation were analyzed using isolated bacterial strains. Bacterial strains were isolated from the industrial affected contaminated soil sample. The selected three bacterial strains were named as SS5, MR2, and MR3. These organisms were identified based on the cultural, morphology and biochemical characteristics and results of SS5 (Pseudomonas fluorescence), MR2 (Bacillus cereus) and MR3 (Bacillus decolorationis). The heavy metals degradation of isolated bacterial strains was analyzed based on the growth of heavy metals containing medium. The heavy metals degrading ability of isolated strains were analyzed at 48 hrs after inoculation. The effect of heavy metals on the growth of pigeon pea (Cajanus cajan L. ) were determined by pot culture experiment and analyzed the germinating and growth ability in different experimental groups showed that Pseudomonas fluorescence and Bacillus cereus have more efficient than Bacillus decolorationis.