Activity of Viscum album L. extract against wood-rot fungi and its potential application in wood preservation

The aim of this study was to investigate the possibility of converting Viscum album bio-waste into more valuable antifungal agents for the wood industry. The study reports the activity against basidiomycete species, including brown and white wood-decaying fungi, as well as the phenolic composition of extracts from three mistletoe subspecies (album, austriacum, and abietis). The resistance of Scots pine sapwood treated with mistletoe extract against Coniophora puteana and Trametes versicolor was also evaluated. All tested extracts at a 100 mg mL−1 concentration caused a complete inhibition of all fungal species growth and were more inhibitory to brown-rot fungi than white-rot fungi. The phenolic profile of extracts depended on mistletoe subspecies and was dominated by phenolic acids. Treated wood showed lower mass loss caused by decay fungi compared to untreated wood. Samples treated with mistletoe extract in different concentrations were characterised by a reduction in the destructive effect of C. puteana in the range of 52-70% compared to untreated wood, and in the case of T. versicolor in the range of 45-85%. The research indicated the potential of using mistletoe extract as a sustainable source of antifungals that may improve the resistance of treated wood against C. puteana and T. versicolor.