Synthetic dye decolorization by three sources of fungal laccase

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 wasthe 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 3 h incubation inpresence of hydroxybenzotriazole (hbt; 5 mm) as the laccase mediator. it was also observed that decolorizationefficiency of all dyes was enhanced by increasing of hbt concentration from 0.1 mm to 5 mm. laccase from a.oryzae was able to remove 53% of methylene blue and 26% of rbbr after 30 min incubation in absence of hbt, butthe enzyme could not efficiently decolorize other dyes even in presence of 5 mm of hbt. in the case of laccasefrom t. versicolor, only rbbr was decolorized (93%) in absence of hbt after 3 h incubation.