Characterisation and variation of agarwood resins from Gyrinops walla
Forest Research Institute Malaysia
School of Science
The genera Aquilaria and Gyrinops of Thymalaeaceae family produce agarwood as a response to damage to their xylem tissues. Agarwood is used for perfumery, incense and traditional medicine. Gyrinops walla is the only agarwood producing species naturally growing in Sri Lanka and it is often harvested illegally from the wild. Research on characteristics of the G. walla resin is limited and insufficient to support its development as an agroforestry crop. The present study sampled a total of 90 G. walla trees from nine natural populations distributed in four agro-ecological zones in Sri Lanka. Resinous tissues were collected and resin contents were solvent extracted. Yields varied from 0.1 to 9.8% with no significant difference between the populations. GC-MS analysis of the G. walla resin identified 21 constituents; agarospirol, d-selinene, alloaromadendrene oxide, spathulenol, and two unidentified 2-(2-phenylethyl)chromone derivatives were found to be common for all tested populations. The chemical composition of G. walla resins was comparable with commercially available agarwood resin of Aquilaria species. The average amount of agarospirol varied from 1.13 to 7.16%. Significant correlations were not found between resin contents and tree diameter or height. Resin characteristics showed no significant difference between the populations. However, variations were observed among trees of the same population.