The Effect of Aspergillus flavus ES Isolate on the Decolourisation of Crystal Violet, Titan Yellow and Congo Red

In the textile and dyeing industries, chemical dyes are increasingly preferred over natural dyes. Chemical dyes are easier to use and more cost effective to synthesize. The firmness and colour variety of chemical dyes is also beneficial. Unfortunately, these chemical dyes are often found in industrial effluent. Decolourising these released dyes can reduce their environmental toxicity. In this study, an isolate of Aspergillus flavus ES was used to decolourise three commercial dyes. As dye concentrations increased, the percentage of decolourisation increased, even as growth of the fungal isolate decreased. Also, an increase in the dye incubation period led to an increase in the decolourisation percentage. Further analysis showed that the organic and fatty acid levels of the Aspergillus flavus ES isolate were affected by the dye. Finally, it was found that increasing dye concentration had a toxic effect on the fungal ultrastructure.