Isolation and selection of white-rot fungi for decolourisation of industrial dyes

Resumen

Textile dyes have complex aromatic structures that result toxic, mutagenic, carcinogenic and cause serious
pollution problems in the ecosystems where are released. White rot fungi (WRF) can be useful in the pollution control
because they produce non-specific oxidases which are able to degrade lignin and other recalcitrant molecules of similar
structure such as polycyclic aromatic hydrocarbons, pesticides and dyes. The purposes of this work were to isolate and
select WRF strains with high capacity to decolourise textile dyes, as well as to analyze the production of ligninolytic enzymes
in presence of different industrial dyes as enzymatic inducers. Thirty strains were collected from woody material
present in several ecosystems of Havana City and Sancti Spíritus, in the period of 2000 to 2004. Isolated corresponded to
eleven different species of ligninolytic basidiomycetes, from them Ganoderma aff. zonatum (B-18) and Pleurotus djamor
(B-36) were the most effective in decolourisation of eleven chemically different dyes and two simulated textile effluents.
As reference in decolourisation assays were used the strains Trametes membranacea (B-1), Lentinus hirtus (B-8) and
Pleurotus djamor (B-9), from the National Botanical Garden and with proved capacity to degrade lignin and the dye
crystal violet. The enzymes laccase and manganese peroxidase of G. aff. zonatum (B-18) were induced in presence of the
mixture of the reactive dyes Cibacron navy FN-B, Cibacron red FN-3G and Cibacron yellow P-6GS and a simulated textile
effluent, suggesting their participation in decolourisation processes.