Isolation and characterization of chromium resistant bacteria for remediation of contaminated effluents
Subject Areas :
1 - استادیارگروه زیست شناسی، دانشگاه آزاد اسلامی، واحد اسلامشهر
Keywords: Heavy metals, Bioremediation, Chromium resistant bacteria,
Abstract :
The pollution of the environment with toxic heavy metals is spreading throughout the world along with industrialprogress. Removal of heavy metals needs advance chemical technology and is more expensive too. The cheaperalternative for this is the bioremediation using heavy metals resistant microorganisms. In this study, 5 heavymetal resistant bacteria were isolated from electroplating effluents collected from Islamshahr. The isolates grewwell on nutrient agar containing 1 mM of chromium (Cr). The resistant isolates were identified on the basis ofmorphological, biochemical and physiological properties. Finally its molecular identity was revealed through16S rRNA analysis. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolates belongto the following genera: Comamonas, Acinetobacter and Acicovorax. The minimum inhibitory concentrations(MICs) of the isolates were determined. All the isolates showed high resistance to chromium with MICs rangingfrom 4-6mM. The results suggest that the isolated strains obtained from effluent owing to its high resistance tochromium have a great potential to be employed for bioremediation of chromium contaminated effluents.