Evaluation of azo dyes degradation potential of Aspergillus strains: A strategy for waste management

Abstract

The negative impact of azo dye emission on the lifestyle of humans, germination of plants, and the survival of marine life forms disturbs the whole food chain. The current investigation uses Aspergillus fumigatus and Aspergillus flavus to evaluate their degradation potential for Sumifex Tourqi Blue and Navy Blue dyes. The loss of the original dye peaks in the visible region by UV–Vis spectra showed the potential of Aspergillus strains to decolorize and degrade azo dyes. The respective decolorization percentages were 75 % and 48 % for Sumifex Tourqi Blue and Navy Blue by A. fumigatus, whereas 63 % and 85 % for both azo dyes by A. flavus. The GC-MS analysis of the degraded product exhibited different compounds such as Furo[2,3-c] pyridine-2-carboxylic acid, 5-(methylthio)-, ethyl ester, Ethanone, 1-(5,6,7,8-tetrahydro-2,8,8-trimethyl-4H-cyclohepta[b]furan-5-yl), Oxazole, 2-[1,1′-biphenyl]-4-yl-5-phenyl, etc. The efficient production of laccase by the fungal strains proved that the enzyme played a crucial role in decolorizing the harmful azo dyes. The most enzyme activity was recorded by A. flavus, 393 % for Sumifex Tourqi Blue and 299 % for Navy Blue by A. fumigatus. Based on their ability to decolorize and degrade such dyes, Aspergillus strains can be a good bioresource for green chemistry to eradicate azo dyes from the environment.