Enzymatic Decolorization of Textile Dyeing Effluents

Abstract

Commercial azo, triarylmethane, antraquinonic, and indigoid textile dyes are efficiently decolorized with enzyme preparations from Pleurotus ostreatus, Schizophyllum commune, Neurospora crassa, Polyporus sp., Sclerotium rolfsii, Trametes villosa, and Mycelioph tora thermophila. The nature of substituents on the dyes' benzene rings influences enzyme activity, and hydroxyl and amino groups enhance decolorization. The presence of lignin peroxidase and/or manganese peroxidase in addition to laccase ( P. ostreatus, S. commune, S. rolfsii, N. crassa) increases decolorization by up to 25%. The effect of textile dyeing auxiliaries depends on the individual enzymes. Polyporus sp. and T. villosa are inhibited up to 20% by copper and iron chelating agents and anionic detergents, while the S. commune enzymes lose up to 70% of their activity.