Biological removal of phosphate from synthetic wastewater using bacterial consortium

The biological phosphorus removal is a microbial process widely used for removing phosphorus from wastewater to avoid eutrophication of water bodies. The study was aimed to screen the efficient phosphate reducing isolates and used to remove phosphate from synthetic wastewater using batch scale process. The three most efficient phosphate reducers were isolated and screened from eutrophic lake water and forest soil samples. The total heterotrophic bacterial analysis of the samples showed the presence of about 38 phosphate reducers based on the minimum inhibitory concentration (MIC) test. Among them, Bacillus sp. RS-1, Pseudomonas sp. YLW-7 and Enterobacter sp. KLW-2 were found to be efficient in phosphate reduction. Among the individual strains, Pseudomonas sp. YLW-7 was noticed to be 68% removal in MSM with glucose at neutral pH. The consortium with combination of Bacillus sp. RS-1, Pseudomonas sp. YLW-7 and Enterobacter sp KLW-2 was effectively removed the phosphate in the synthetic medium when compared to individual strains. The phosphate removal was observed to be maximum of 92.5% in mineral salts medium (MSM) at pH 7and 5, and 63.4% in synthetic phosphate solution at neutral pH with lactose as a carbon source by the consortium after 72 h. Thus the microorganisms may use the contaminants as nutrients and as energy sources or it may be utilized by co-metabolism. Therefore, these bacterial isolates might be used in the remediation of phosphate contaminated environments.