Biological decolourization of textile industry wastewater by a developed bacterial consortium

Abstract

Most currently employed textile effluent decolourization methods use physical and chemical processes where dyes do not get degraded instead concentrated or transferred into a solid phase. Therefore, further treatment processes are required to destroy dyes from the environment. In contrast, biological decolourization may result in degradation of the dye structure due to microbial activities and hence biological processes can be considered environmentally friendly. In the present study, bacterial strains with dye decolourization potential were isolated from the natural environment and their ability to decolourize four different reactive textile dyes was studied individually and in a bacterial consortium. The developed bacterial consortium composed with Proteus mirabilis, Morganella morganii and Enterobacter cloacae indicated more than 90% color removals for all four dyes and optimum decolourization of the dye mixture was observed at 40°C and pH 7. The developed bacterial consortium decolourized 60% of dyes in textile industry effluent at 35 °C and pH 7 showing their ability to endure in highly complex and toxic environments and application in textile industry wastewaters.