Extractives in some tropical woods

Abstract

Total amount and composition of extractives from 12 different tropical wood species were determined by sequential extraction followed by silylation and GC, GC/MS analysis. Hexane and then acetone/water (5:1) mixture was used successively for the extraction. Generally, very low amounts of lipophilics were found (0.05-0.38 mg/g) and the constituent consisted of fatty acids. Hydrophilics were composed of phenolic acids, flavonoids, sterols, stilbenes and a lignan. The highest amount of hydrophilics was found in Afzelia (36.1 mg/g), while the lowest in Wenge and Opepe (0.30 mg/g). Also, cold-hot water, 1% NaOH and some solvent (acetone, dichloromethane) solubilities were determined. The solubility values of tropical woods except for Canalete were found to increase in the order of solvent, cold water, hot water and 1% NaOH.