Physical, chemical and biological properties of several wood species were investigated in order to highlight the main factors involved in wood natural durability and wood characteristic using a principal component analysis. Interaction of wood with water were evaluated using contact angle measurements to determinate wood wettability by water and wood impregnability tests with water allowing to calculate relative humidity of wood under different condition and its swelling coefficient. Chemical composition of wood was evaluated on extract free sawdust using classical method for determination of cellulose, lignin, hemicellulose using nitric acid, sulfuric acid or sodium chlorite, respectively. Py-GC-MS was used to determine lignin/polysaccharides ratio and those of the different lignin monomers like syringyl/guaiacyl ratio. Extractives contents were obtained after Soxhlet extraction with four solvents of increasing polarities: dichloromethane, acetone, toluene/ethanol (2/1, v/v) and water. Decay durability of the different wood species studied was carried out on extracted and unextratcted wood blocks using three white rot Trametes versicolor, Pleurotus ostreatus and Pycnoporus sanguineus and three brown rot Poria placenta, Gloephyllum trabeum and Coniophora puteana. Effects of extractives present in sawdusts on the inhibition of the fungal growth of the different wood decaying fungi was also measured. Correlations analysis indicated that the hydrophobicity measured through the contact angle, water impregnability, polysaccharides/lignin ratio, density and biological reactivity of the extracts towards GST appear as the main parameters explaining wood natural durability confirming the multifactorial aspect of wood natural durability.

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