Evaluation of Microbial Systems for Biotreatment of Textile Waste Effluents in Nigeria: Biodecolourization and Biodegradation of textile Dye

Abstract

The evaluation of some microbial species for the decolourization and degradation of textile dye has been investigated. Six microbial strains were isolated from soil contaminated with textile waste effluents using thespread plate technique and the isolates were identified as bacterial isolates (Pseudomonas fluorescence, Pseudomonas nigificans, and Pseudomonas gellucidium) and fungal isolates ( Aspergillus niger, Proteus morganii and Fusarium compacticum} based on gram staining, morphological and biochemical tests. They were evaluated for theircapability to remove colour and degrade dye, reduce chemical oxygen demand (COD) and biological oxygen demand (BOD) levels of textile waste effluents. The results revealed that all the bacterial and fungal isolates have a good potential to remove colour and degrade dye, reduce the COD and BOD levels of the textile waste effluents withpercent colour removal, COD and BOD reductions between 39 and 48%, 74 and 97% and 77 and 95%, respectively. Binary mixed culture of Pseudomonas fluorescence and Aspergillus niger was efficiently utilized for the removal of different initial concentration (10, 15, 20, 25 and 30 mg/l) of dye from textile waste effluents. It had a higher percentdecolourization than individual isolates. The stirred tank bioreactor was found to be very effective for efficient biotreatment of textile waste effluents.