Decolorization of reactive dyes by the white rot fungus Trametes versicolor in sequencing batch reactors

The white rot fungus Trametes versicolor was shown to be capable of decolor izing three reactive dyes in a sequencing batch process, using glucose as t he carbon and energy source over an extended period without supplementation of new mycelium. Decolorization activity was related to the-expression of extracellular peroxidases and could be continuously reactivated by sheering the suspended pellets. Pure culture experiments were carried out simultane ously in agitated Erlenmeyer flasks and in completely. stirred tank reactor s with two azo dyes, C.I. Reactive Black 5 and C.I. Reactive Red 198 as wel l as the anthraquinone dye C.I. Reactive Blue 19 (Brilliant Blue R). Result s show high and stable degrees of decolorization of 91%-99% in both systems , which could be repeated without decrease in activity overtime. Under nons terile conditions only five cycles of decolorization could be achieved. An increasing bacterial population suppressed fungal growth and the formation of peroxidases. (C) John Wiley & Sons, Inc.