Biodegradation of Acid Blue 113 Containing Textile Effluent by Constructed Aerobic Bacterial Consortia: Optimization and Mechanism

Abstract

A bacterial consortium was constructed using five different bacterial strains isolated from the effluent with the ability to degrade Acid Blue 113, a diazo dye. These organisms were identified as Citrobacter freundii (2 strains), Moraxella osloensis, Pseudomonas aeruginosa using 16S rRNA analysis and Pseudomonas aeruginosa CLRI BL22. The consortium was found to degrade 90% of the dye by 22 h in 80% diluted textile effluent supplemented with glucose and ammonium nitrate. Optimization studies using Response Surface Methodology have confirmed that the degradation process was predominantly influenced by agitation and pH where as glucose was found to have negative effect. TLC analyses indicated the presence of metanilic acid and peri acid in 24 h sample which disappeared by 48 h. The GC-MS analysis has confirmed the presence of methyl salicylic acid, catechol and β-ketoadipic acid with the RT values of 7.71, 10.88 and 15.04 respectively confirming the complete degradation of Acid Blue 113.