Some fungi are very tolerant on copper compounds which are one of the most frequently used wood preservatives; and this phenomenon has been known for more than 50 years. Fungi present a threat to wood impregnated with copper compounds. On other hand, wood treated with copper compounds represent a big environmental problem. To avoid environmental pollution bioremediation method could be used to decay used impregnated wood. Bioremediation processes requirecheap and effective nutrient sources, containing significant amounts of nitrogen, e.g. corn steep liquor (CSL). To elucidate fungal copper tolerance in a nitrogen-rich environment, experiments were performed on a nutrient medium and with wood. CSL was added to nutrient medium containing different copper concentrations. Sterilized CCB-impregnated and control CSL-supplemented specimens were exposed to copper-tolerant (Antrodia vaillantii, Leucogyrophana pinastri) and copper-sensitive (Postia placenta, Gleophyllum trabeum, Trametes versicolor, Hypoxylon fragiforme) fungal species according to the mini block procedure. The result of both experiments showed inhibited growth of the copper-tolerant fungi on nutrient medium containing copper and decreased decay of CCB-preserved wood.
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