Application of the aquatic fungus Phoma sp. (DSM22425) in bioreactors for the treatment of textile dye model effluents

Background: Textile dyes are hardly removed from effluents by conventional wastewater treatment but can be degraded by a number of physicochemical processes nevertheless having specific limitations. The development of bioremediation processes may provide a viable alternative. Results: Resting cells of three aquatic fungal strains, Alternaria sp. (Tt-S1), Coniothyrium sp. (Kl-S5) and Phoma sp. (DSM22425), were evaluated for their ability to decolorize model effluents of different dye application classes. Phoma sp., who decolorized all four applied model wastewaters (MWW), was immobilized on a polyester-based fleece material originally designed for the use as cooker-hood filters, and applied in internal loop airlift and bubble column reactors in repeated batch mode under sterile and nonsterile conditions. Depending on the applied MWW and bioreactor setup, a decolorization by more than 90 % was achieved in three consecutive treatment cycles and a total operation time of 16 days. In an upscaled reactor (10 L), Phoma sp. decolorized a MWW for acid dyes by 61 %. Chemical oxygen demand of the MWW was reduced by 36 %. Conclusion: The presented results underline the potential of aquatic fungi for the development of textile dyeing effluent treatment processes.