The Application of Copper and Silver Nanoparticles in the Protection of Fagus sylvatica Wood against Decomposition by Fomes fomentarius

Abstract

Wood technology is constantly looking for environmentally friendly technological solutions. It seems that nanotechnology can provide green and environmentally friendly alternatives for wood protection. In this study, the antifungal activity of silver and copper nanoparticles against the white rot fungus Fomes fomentarius was investigated under in vitro conditions and with respect to the protection of Fagus sylvatica wood. In both experiments, 5, 25 and 50 ppm of nanoparticles were used. The results of the in vitro test showed selective antifungal activity of the nanoparticles. All concentrations of copper nanoparticles stimulated mycelial growth. The stimulation was inversely proportional to the concentration. Silver nanoparticles inhibited fungal colony growth at the highest concentration (50 ppm) and did not affect growth at concentrations of 5 and 25 ppm. Silver nanoparticles increased the rot resistance of beech wood, but only at the highest concentration. Decay caused by F. fomentarius was stimulated by copper nanoparticles at the highest concentration. Probably, the fungus used copper as a micronutrient for better growth and increased the activity of extracellular enzymes. Our results from in vitro tests are consistent with those obtained on beech wood specimens, showing that the concentrations of the two nanoparticles used were too low to protect the beech wood from decomposition by xylophagous fungus.