Decolorization and Degradation of Reactive Blue Dye Used in Jute and Textile Industries by a Newly Isolated Bacillus sp.

For biodegradation of reactive dyes used in jute and textile industries, bacteria were isolated from a dyeing mill effluent. Bacteria having a remarkable ability to decolorize and degrade reactive dye were screened by using dye Reactive Dark Blue WR (RDB-WR). Cultural, morphological and biochemical characteristics were observed, and based on these seven isolates having higher decolorizing capability was identified. Among these isolates, one of the prominent dye decolorizing isolates Bacillus sp. was taken for decolorization study. Under different physicochemical conditions, decolorization and degradation capabilities of Bacillus sp. were optimized by using RDB-WR, a dye commonly used in the jute and textile industries. This bacterium decolorized and grew well up to 500 mg L-1 of RDB-WR. Bacillus sp. showed significant decolorization approximately 86% at 200 mg L-1 of RDB-WR after 96 h of incubation. Optimum degradation of dye was achieved at 37 °C. Maximum decolorization was observed at pH 7.0 under static conditions. The study confirmed the potential of Bacillus in the biodegradation of Reactive Dark Blue WR. This bacterial isolate might be prospective in the biological treatment of dyeing mill effluents due to the high extent of decolorization.