Decolorization of Direct Orange 37 using Bacillus pacificus isolated from textile industry effluent of Bangalore, India

This study was conducted to examine the decolorization of textile dye, Direct Orange 37 using an organism isolated from the effluent of the textile industry in Bangalore. Using 16S rRNA gene based molecular method; the isolate was identified as Bacillus pacificus. The optimized conditions for decolorization were found to be a pH of 7, temperature of 35 °C, 100 mgl-1 concentration of the dye, 100 rpm shaking speed, 4 % v/v of inoculum, 100 mgl-1 each of maltose and peptone. To screen out the variables significantly influencing the decolorization of the dyes, Plackett-Burman design was used. The levels chosen in the design were based on the one-factor-at-a-time approach. Shaking speed, inoculum concentration, dye concentration and maltose were found to be significant variables. The predictions made by the model were validated through decolorization experiments.