Phenolic and lipophilic extractives in Pinus merkusii Jungh. et de Vries knots and stemwood
Résumé
Previous studies reported that knotwood of several European Pinus sp. contains extractives contents much higher than stemwood consisting mainly of phenolic compounds which may find valuable applications in cosmetic, nutraceutic or pharmaceutic sectors. At the same time, no comprehensive studies on the tropical species Pinus merkusii have been reported. Determination of extractives amounts present in sapwood, heartwood and knotwood of P. merkusii has been performed and their chemical composition analyzed using GC-MS and LC-MS. Antioxidant and antifungal activities were also evaluated by DPPH method and growth inhibition method, respectively. The results showed that knotwood contains more extractives than heartwood, the latter containing more extractives than sapwood. Knotwood extracts contain mainly lignans, especially nortrachelogenin, stilbenes and resin acids, while heartwood extracts were constituted mainly of stilbenes, especially pinosylvin monomethyl ether, pinosylvin and pinosylvin dimethyl ether and of flavonoid like pinocembrin. Acetone knotwood extract presents the higher antioxidant activity, while acetone heartwood extract possesses the higher antifungal activities against the two tested fungi Trametes versicolor and Poria placenta.