Research Article
Arun Kumar, Jayata Chopra, San
Abstract
Azo dyes account for most of all textile dyes stuffs produced and have been the most commonly used synthetic dyes in textile, food, paper making and cosmetic industries. Release of azo dyes into the environment from the effluents of dye- utilizing industries has become a major concern in wastewater treatment. Some azo dyes have been linked to human bladder cancer, spleenic sarcomas, hepato-carcinomas & chromosomal aberrations in mammalian cells. Bacillus subtilis ‘RA29’ (NCBI accession no: JF901735) was applied on four different azo dyes (Congo red, Amido black, Acid orange & Rhodamine B) for the decolorization. In Yeast Malt broth (YMB), Bacillus subtilis ‘RA29’ showed 98.23% decolorization of Congo red, 78.32% Amido black, 96.69% Acid orange & 6.69% Rhodamine B at pH 7.0 after 20 hr of incubation at 370C. During the growth and Congo red decolorization kinetic study, the maximum decolorization (99.7%), cell yield (347.80) with biomass concentration 17.216mg/ml was observed after 16 hr of incubation at temperature 370C under static aerobic condition. The enzyme activities of laccase, azoreductase, peroxidase enzymes in partially purified extracellular crude protein were detected as 7.34U/ml, 0.168 U/ml, 0.134 U/ml respectively. Liquid chromatography mass spectroscopy (LCMS) studies detected the tentative presence of AcetoAcet-P-ChloroAnilide, 3-(2,2-dichlorovinyl)-2,2-dimethyl cyclopropane-1-carboxylic acid chloride, N-{4-[(4-Bromophenyl) sulfamoyl] phenyl}-N2-[(4-chlorophenyl) sulfonyl]-N2 (2 ethoxyphenyl) glycinamide and 2, 2, 2-Trichloroethanol at retention time 1.571 min, 13.68 min, 19.153 min and 18.234 min respectively