Degradation of creosote by Pleurotus ostreatus mycelium in creosote-treated wood.

The detoxification of creosote-treated wood is an actual problem that should be faced in a short time, since the law imposes the removal of the polluted materials. Biotechnologies based on the use of white-rot fungal species can be a suitable way, since their mycelia are able to grow on ligninocellulosic materials and to oxidize aromatic organic molecules through extracellular enzymes. The mycelium of Pleurotus ostreatus SMR 684 was grown in Petri dishes on different mixtures of creosote-treated wood and wheat straw. Although in a different extent due to the creosote concentration, mycelium grew rapidly producing abundant biomass. Results obtained after 30 days from mycelium inoculation show a remarkable decrease of total phenols (greater than 75%), heterocyclic compounds (from 40 to 85%, depending on the molecu-lar structure) and total polycyclic aromatic hydrocarbons (65%).