Isolation and molecular characterization of some copper biosorped strains

ABSTRACT

TThe biosorption of copper [II] from aqueous solution using different bacterial strains was studied. Copper-biosorbing bacteria were isolated from tannery effluent collected from Borg Al-Arab, Alexandria, Egypt. These isolates displayed different degrees of copper biosorption under aerobic conditions. Based on 16S rDNA gene sequence analysis, three of them [S2, S5 and S7] were identified as Chryseobacterium sp., Enterobacter sp. and Stenotrophomonas sp., respectively. Initial copper [II] ion concentrations from 25-250 mg/L at constant temperature 30°C were studied. The residual copper [II] concentration and its toxicity effect in solution were determined using atomic absorption spectrophotometer and bioluminescent bioreporter. The bioluminescence inhibition of strain [S5] reached to 91.4% as compared with the strain [S7] reached to 83.3% at 225 mg/L of copper ion where the maximum biosorption efficiency for S5 and S7 were 71% and 70.1% correspondingly using atomic absorption. The biolumi-nescent bioreporter was proved to be fast and accurate technique for measurement the toxicity effect of residual copper [II] in solution