Decolourisation of Reactive Black 5 Dye by a White Rot Fungi Trametes versicolor

Azo dyes represent the largest class of organic colourants listed in the Colour Index (60-70%) and makeup vast majority of the dyes discharged by textile industry. Due to high cost, low efficiency and inapplicability of several physico-chemical decolourisation techniques, biological processes such as the use of white-rot fungi provide an alternative to this problem. In the present work, ability of Trametes versicolor to decolourise an azo dye viz., Reactive Black 5 was evaluated under shaker conditions by statically grown culture using different sources of carbon and nitrogen. At the end of the 8 hours, Reactive Black 5 was decolourised to an extent of 25.12% in the medium containing glucose. The nitrogen source that supported the highest decolourisation (62.93%) of the dye at the end of 24 hours was yeast extract. Further optimization was carried out by the Orthogonal Array design for the optimization of the medium and to determine the effect of glucose, yeast extract and copper sulphate on the dye decolourisation. The data were analysed using Minitab software 15.