Effect of different carbon sources on decolourisation of an industrial textile dye under alkaline-saline conditions

Abstract

White-rot fungal strains of Trametes versicolor and Phanerochaete chrysosporium were selected to study the decolourisation of the textile dye, Reactive Black 5, under alkaline–saline conditions. Free and immobilised T. versicolor cells showed 100 % decolourisation in the growth medium supplemented with 15 g l-1 NaCl, pH 9.5 at 30 C in liquid batch culture. Continuous culture experiments were performed in a fixed-bed reactor using free and immobilised T. versicolor cells and allowed 85–100 % dye decolourisation. The immobilisation conditions for the biomass and the additional supply of carbon sources improved the decolourisation performance during a long-term trial of 40 days. Lignin peroxidase, laccase and glyoxal oxidase activities were detected during the experiments. The laccase activity varied depending on carbon source utilized and glycerol-enhanced laccase activity compared to sucrose during extended growth.