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 cometabolism. Therefore, these bacterial isolates might be used in the remediation of phosphate contaminated environments

Dye decolorizing potential of a novel fungus Coriolus versicolor ML04 in the medium optimized by response surface methodology

The potential of the white rot fungus, Coriolus versicolor ML04 to decolorize the widely used textile dye Blue BB was tested by employing statistical optimization. Response surface methodology (RSM) involving a central composite design (CCD) was applied to evaluate the interactive effects of four significant factors in different ranges i.e.; glucose (0.5 - 2.5 g/L), yeast extract (0.4 -1.2 g/L), dye concentration (100 - 500 ppm) and inoculum size (5 - 20 percent v/v) to decolorize the Blue BB. The results demonstrated the effectiveness of the statistical experimental design and the ability of C. versicolor ML04 for maximum dye decolorization (>96 percent) at the optimum conditions of the significant factors.

Occurrence of Aeromonas hydrophila in acute gasteroenteritis among children.

BACKGROUND & OBJECTIVE: The interest on the occurrence multidrug resistance and pathogenicity of Aeromonas hydrophila is increasing worldwide since it causes gasteroenteritis to children. Though reports on the occurrence of gasteroenteritis among children due to A. hydrophila in Tamil Nadu are available from certain areas, no information is available from Coimbatore. Hence, this study was undertaken to find out the occurrence of the pathogenic A. hydrophila in diarrhoeal stool of children, particularly in Coimbatore region. METHODS: Isolation and identification of A. hydrophila was carried out from stool samples collected from children with acute diarrhoea. Multiple antibiotic resistance was determined by disc diffusion method. The pathogenicity of A. hydrophila was confirmed by production of haemolysin, protease and slime. RESULTS: Of the 216 samples, 21 (9.7%) were positive for A. hydrophila. Among them 20 isolates were resistant to bacitracin. Most of the isolates showed multiple antibiotic resistance. Among the 21 isolates, protease and haemolysin producers were 100 and 95 per cent respectively. About 76 per cent of the isolates produced slime. INTERPRETATION & CONCLUSION: The results of the present study indicated the presence of pathogenic A. hydrophila in the study area causing diarrhoea among children.