WITHDRAWN: Heavy metal removal competence of individual and bacterial consortium, evolved from metal contaminated soil

Abstract

Heavy metals represent a significant worldwide environmental problem due to the toxicity towards livings. Therefore, the removals of toxic metals from the environmental samples have a challenging process in recent years. The present study investigated heavy metal removal from aqueous solution by a bacterial consortium and individual bacterium isolated from metal-polluted soil. In this study, the strains B. thuringiensis A1-3, P. aeruginosa A-33, B. cereus A1-5, and B. anthracis A1-7 were actively showed metal tolerance in screening and further used for biosorption study in lab-scale method. The maximum biosorption efficiency was noted at Cu 92.7% and Zn 90.3% by bacterial consortium. The low level of biosorption of Pb was observed 86% by consortium compared with individual bacteria. P. aeruginosa A33 achieved the maximum Pb biosorption. In conclusion, the bacterial consortium has a promising alternative for removing Cu and Pb. The P. aeruginosa A33 exhibited as potent bacteria for removing Zn in an aqueous solution. Antibiotic resistance and Multiple Antibiotic Resistance Index (MAR) of metal resistant bacteria were also investigated. Overall it was observed that, a bacterial consortium with the combination of four bacterial strains is feasible for multi-metal removal from the metal contaminated environment.