Physicochemical Analysis of Textile Dye Effluent and Screening the Textile Dye Degrading Microbial Species

Abstract

The dye degradation and decolorization processes, which include many physical and chemical methods having inherent drawbacks, like costing, economicall unfeasible (require more energy and chemicals), unable to remove some of the recalcitrant dyes and production of large amount of sludge which if not properly treated, in turn can cause secondary pollution. So, biological degradation, being eco-friendly and inexpensive method, is considered as an effective method for the removal of toxic azo dyes. Our present study is therefore aimed to isolate azo dye decolorizing bacteria from dyeing industry effluent and to assay their dye decolorization capability in order to use them as an efficient bio agent for decolorizing and mineralizing toxic azo dyes. In this research we also tried to determine the physicochemical analysis of textile dye effluent. We tried to determine the BOD and COD of the collected effluent samples, which were found to range from 50 to 100 ppm and 200 to 400 ppm. Temperature of the three collected samples was found to vary from 26°C to 36°C and pH was in the range of 8.6 to 9.7. Total bacterial count was found within the range of 1.3x10 5 (CFU/ml) to 9.2 x 10 5 (CFU/ml). For the purpose of studying dye decolorization assay, twelve bacterial colonies were isolated on the basis of their unique colony features from the collected effluent samples and from them seven bacterial isolates were selected by further screening method and observed their degradation on Novacorn Orange C3R dye.