Decolorization of Textile Dye by Brevibacillus laterosporus (TS5) and Influencing Factors Optimization through Response Surface Methodology

Abstract

The dye removal bacteria Brevibacillus laterosporus (TS5) was isolated from dye contaminated soil, and it’s identified by 16S rDNA sequencing method. The prospective bacterial strain exhibited a highest decolorization (97.8%) in Luria-Bertani broth medium. Among the operational factors, Plackett-Burman design, experimental results indicated that pH, incubation period, and yeast extract significantly contributed for the dye decolorization. Also, dye concentration, starch, temperature, and inoculum size noted as insignificant factors on dye decolorization. Central composite design applied for optimization of important factors to enhance the dye decolorization by Brevibacillus laterosporus (TS5). The optimal values of significant factors were determined by the Response surface methodology (RSM) as follows: 0.60% (w/v) yeast extract, 7.23 pH and 61.45 hrs incubation period, which assisted for Brevibacillus laterosporus (TS5) to attain 90.66% dye removal. Brevibacillus laterosporus (TS5) showed 90.08% decolorization in validation experiments by the support of optimal factors, and implies that explored strain could be a suitable candidate for bioremediation of dye containing effluents.