The main task was to define contents of extractives and portions of entire phenols in wood knots and in its surrounding wood of coniferous trees. We used Soxhlet method device firstly to extract hydrophobic (lipophilic) components with cyclohexane and then to extract hydrophilic components with a mixture of water and acetone. UV/VIS spectroscopy method based on acetone extract was used to define portions of entire phenols in wood knots and in its surrounding wood. The results were presented in equivalents of gallic acid mass concentration. The dry substance share in wood knots was 93.33 %, and in its surrounding wood it was 92.08 %. Lipophilic and hydrophilic substance shares in wood knots was 14.73 %, and in its surrounding wood 2.59 %. The average content of entire phenols was about six times higher in knots than in its surrounding wood. It is assumed that phenol substances protect wood tissue after breaking of branches against irruption of pathogenic microorganisms.
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