Biodegradation of the major color containing compounds in distillery wastewater by an aerobic bacterial culture and characterization of their metabolites

Abstract

This study deals the biodegradation of the major color containing compounds extracted from distillery wastewater (DWW) by an aerobic bacterial consortium comprising Bacillus licheniformis (DQ79010), Bacillus sp. (DQ779011) and Alcaligenes sp. (DQ779012) and characterization of metabolic products. The degradation of color containing compounds by bacteria was studied by using the different carbon and nitrogen sources at different environmental conditions. Results revealed that the bacterial consortium was efficient for 70% color removal in presence of glucose (1.0%) and peptone (0.1%) at pH 7.0 and temperature 37°C. The HPLC analysis of control and bacterial degraded samples has shown the reduction in peak area as well as shifting of peaks compared to control indicating the bacterial degradation as well as transformation of color containing compounds from DWW. The comparative LC–MS–MS and other spectrophotometric analysis has shown the presence of dihydroxyconiferyl alcohol, 2, 2′-bifuran-5-carboxylic acid, 2-nitroacetophenone, p-chloroanisol, 2, 3-dimethyl-pyrazine, 2-methylhexane, methylbenzene, 2, 3-dihydro-5-methylfuran, 3-pyrroline, and acetic acid in control samples that were biodegraded and biotransformed into 2-nitroacetophenone, p-chloroanisol, 2, 2′-bifuran, indole, 2-methylhexane, and 2, 3-dihydro-5-methylfuran by bacterial consortium. In this study, it was observed that most of the compounds detected in control samples were diminished from the bacterial degraded samples and compounds 2, 2′-bifuran and indole with molecular weight 134 and 117 were produced as new metabolites during the bacterial degradation of color containing compounds from DWW.