Enhanced biodegradation and detoxification of disperse azo dye Rubine GFL and textile industry effluent by defined fungal-bacterial consortium

In this study, a defined consortium-AP of Aspergillus ochraceus NCIM-1146 fungi and Pseudomonas sp. SUK1 bacterium was studied to assess its potential for enhanced decolorization and detoxification of azo dye Rubine GFL and textile effluent. Developed consortium-AP showed enhanced decolorization of dye (95% in 30 h) and effluent (98% ADMI removal in 35 h) without formation of aromatic amines under microaerophilic conditions. Individual A. ochraceus NCIM-1146 showed only 46% and 5% decolorization of the dye and effluent. However, Pseudomonas sp. SUK1 showed 63% and 44% decolorization of the dye and effluent respectively with the production of aromatic amines. Induction of laccase, veratryl alcohol oxidase, azo reductase and NADH-DCIP reductase in the consortium-AP suggests synergetic reactions of fungal and bacterial cultures for enhanced decolorization process. Differential fate of metabolism of Rubine GFL by an individual and consortium-AP cultures were proposed on the basis of enzymatic status, FTIR and GC-MS analysis. Furthermore, consortium-AP also achieved a significant reduction in COD (96%), BOD (82%) and TOC (48%) of textile effluent. The results of toxicity studies suggest that this consortium may effectively be used for complete detoxification of dye and effluent and has potential environmental implication in cleaning up azo dyes containing effluents.

► Defined consortium-AP showed an enhanced degradation than monocultures.
► Induced oxidoreductive enzymes pattern was found in the consortium.
► Mechanism involved in consortium and individual degradation of dye is discussed.
► COD and TOC reduction gives additional insight into the effluent mineralization.
► Toxicological study confirms the detoxification of dye and effluent.