Fungal bacterial consortium for the textile dyeing wastewater treatment

Abstract

Textile industry is one of the major industries in India, that consumes more than 100 L of water to process 1 kg of textile materials and has contributed heavily to polluting surface- and ground water resources. The decolorization and detoxification of industrial textile dye effluents are the most important aspects showing a major concern to meet the environmental regulations due to the carcinogenic and toxic effects of untreated textile effluents upon their discharge. An increasing industrial demand for remediating the textile dyeing wastewater in an effective way has led to the pervasive acceptance of bioremediation. The present study is to develop an efficient formulation of a fungal-bacterial consortium for the degradation and detoxification of such wastewater. Pleurotus citrinopileatus MTCC 1796, a fungal strain, was improved for its laccase production by inducing mutation mediated by UV light irradiation. The survival rate of P. citrinopileatus MTCC 1796 got decreased with increase in UV light and the production of laccase was increased. The laccase from the wild and mutant strains was partially purified and it was found that the mutant strain- produced laccase had a higher activity (16.32 U/mL), while the wild strain-produced laccase expressed comparatively a lower activity (9.75 U/mL). The decolorization efficiency of laccase from the wild and mutant strains was individually tested on Basic Blue 7 (BB7), a triaryl methane class dye. It was found that the crude laccase from the mutant strain of P. citrinopileatus MTCC 1796 decolorized 100 mg/L of BB7 at pH 6.0 and 37°C within 150 min. newline