Fungal dye decolourization: recent advances and future potential

Dyes released by the textile industries pose a threat to the environmental safety. Recently, dye decolourization through biological means has gained momentum as these are cheap and can be applied to wide range of dyes. This review paper focuses on the decolourization of dye wastewaters through fungi via two processes (biosorption and bioaccumulation) and discusses the effect of various process parameters like pH, temperature, dye concentration etc. on the dye removing efficiency of different fungi. Various enzymes involved in the degradation of the dyes and the metabolites thus formed have been compiled. Genetic manipulations of microorganisms for production of more efficient biological agents, various bioreactor configurations and the application of purified enzymes for decolourization, which constitute some of the recent advances in this field, have also been reviewed. The studies discussed in this paper indicate fungal decolourization has a great potential to be developed further as a decentralized wastewater treatment technology for small textile or dyeing units. However, further research work is required to study the toxicity of the metabolites of dye degradation and the possible fate of the utilized biomass in order to ensure the development of an eco-friendly technology.