Durability of Prunus africana: Evidence of Biocidal and Lipophilic Properties Responsible for Natural Durability

Analysis of the prunus africana sapwood and heartwood extracts was studied with the aim of understanding the reasons for it's natural durability. Soxhlet extraction of wood powder using different solvents was done. The extracts were tested against the fungi coriolus versicolor, Poria placenta and Aureobasidium pullulans at concentrations of 50, 100, 500 and 1000 ppm. Soxhlet extraction of wood blocks using the same solvents was also carried out and the wood blocks finally tested against fungi and termites. The results showed high exhibition rate against fungi at low extract concentrations. Extracted wood blocks showed low resistance against termites while the un-extracted ones were resistant. Analysis of the products present in hexane, dichloromethane, acetone, toluene/ethanol and water extracts by HPLC indicates presence of phenols and lipophilic compounds, which could be associated with the preceding results. Inhibition against fungi increased with extract concentration and decreased with time. In some instances at high concentration, fungal growth started after the control Petri-dish was fully colonized. Inspite of the fungal and termiticidal properties of certain products contained in the extracts, these properties do not entirely explain the reasons for the high durability. Chemical synthesis with formulations based on the natural components present in the extracts of such durable wood could be interesting as potential additives in fungicides and insecticides. Such formulations based on natural compounds could environmentally friendly