Comparison of synthetic dye decolorization by whole cells and a laccase enriched extract from Trametes versicolor DSM11269

Abstract

Trametes versicolor strain DSM 11269 was found to decolorize six out of seven different synthetic dyes when grown on dye-containing agar plates. Using a laccase enzyme extract, enriched from the fungal liquid culture supernatant, the anthraquinone derivative dyes (Alizarin Red S and Remazol Brilliant Blue R) were decolorized in three hours at 50°C by 55 and 70%, respectively. The four azo compounds (Amaranth, Cibacron Brilliant Red 3B-A, Direct Blue 71 and Reactive Black 5), and the indigo molecule (Indigo Carmine), showed a higher resistance to decolorization (<10% in 6 h), although of them (Amaranth, Reactive Black 5 and Indigo Carmine) were efficiently decolorized by T. versicolor in agar plate assays. This suggests that different oxidizing activities from laccase alone may be involved in the decolorization process.

Key words: Synthetic dyes, Trametes versicolor, decolorization, white-rot fungus.