Biodegradation of Basic Violet 3 and Acid Blue 93 by Pseudomonas putida

Basic violet 3 (BV) and acid blue 93 (AB) belong to the most important group of synthetic colorants. These dyes are used extensively in textile, paper, and leather industries. It is considered as xenobiotic compound, which is recalcitrant to biodegradation. Pseudomonas putida MTCC 4910 was able to utilize BV and AB as a carbon source in liquid media. Effects of pH, temperature, NaCl concentrations, nitrogen sources, initial inoculum size, and initial dye concentration on degradation were studied. The optimum pH and temperature for the degradation of BV and AB were pH 7 and 6, and 37 and 45 degrees C, respectively. Addition of yeast extract enhanced the degradation process. Gas chromatography-MS analysis confirmed the biodegradation of BV and AB. The products formed during the reduction of BV were N,N-dimethyl-N,N-dimethyl-N-methyl parasoaniline, N,N-dimethyl-N,N-dimethyl-parasoaniline, N,N-dimethyl-N,N-methyl parasoaniline, N,N-dimethylparasoaniline, N-methyl parasoaniline and parasoaniline, and three intermediate compounds were oberved during the reduction of AB. The present study highlighted the importance of using P. putida in textile effluent for the effective treatment of textile dyes.