Synthetic dye decolorization by three sources of fungal laccase

Abstract

Decolorization of six synthetic dyes using three sources of fungal laccase with the origin of Aspergillus oryzae, Trametes versicolor and Paraconiothyrium variabile was investigated. Among them the enzyme from P. variabile was the most efficient which decolorized Bromophenol blue (100%), Commassie brilliant blue (91%), Panseu-S (56%), Rimazol brilliant blue R (RBBR 47%), Congo red (18.5%) and Methylene blue (21.3%) after 3h incubation in presence of hydroxybenzotriazole (HBT 5mM) as the laccase mediator. It was also observed that decolorization percent of all dyes was enhanced by increasing of HBT concentration from 0.1mM to 5mM. Laccase from A oryzae was able to remove 53% of methylene blue and 26% of RBBR after 30min incubation in absence of HBT but the enzyme could not efficiently decolorize other dyes even in presence of 5mM of HBT. In the case of laccase from T. versicolor, only RBBR was decolorized (93%) in absence of HBT after 3h incubation.