Abstract: Decolourization and degradation of two dye house effluents (DHEs) have been studied using a developed bacterial consortium. Batch experiments were optimized at shake flask level in terms of pH, temperature, culture condition, carbon and nitrogen source. Bacterial consortium was found to be active between pH 6-10 and temperature 25-40 °C under static condition. Among different carbon and nitrogen sources studied, addition of sucrose, fructose, glucose and beef extract were found to support the degradation of both Effluent-2 and 3 (E-2, E-3). Decolourization and degradation profiles of E-2 and E-3 DHEs were studied to optimize the treatment time. Reduction in BOD, COD and ADMI (American Dye Manufacturers' Institute) values were more than 95%, which proved the treatment efficiency of the developed consortium against both the DHEs Moreover, FTIR and HPLC spectral data analysis and enzyme induction pattern confirmed biodegradation of all the DHEs. Intracellular azoreductase, NADH-DCIP reductase and laccase played significant role in degradation. Phytotoxicity and microbial toxicity were reduced in the range of 70-80% and 40-46%, respectively. This results indicated production of non-toxic metabolites. The study gave significant information for the bio-treatment of DHEs containing various heavy metals using a developed bacterial consortium. |