Analysis of Lipophilic extractives in populusxeuramericana 'Neva'

Lipophilic extractives in the stemwood and bark of Populus × euramericana 'Neva' were analyzed by GC, GC-MS, and high-performance size exclusion chromatography (HPSEC). The top stemwood and bark contained much larger amounts of lipophilic extractives than the corresponding bottom ones. The lipophilic extractives identified were composed of five component groups, i.e. glycerides, steryl esters, free fatty acids, sterols and free fatty alcohols, both in the stemwood and bark. 4-Hydroxycinnamic acid esters of fatty alcohols were identified in a small amount in this wood species. Glycerides, mainly triglycerides, were the largest component group of the lipophilic extractives, and linoleic (18:2) acid was the major fatty acid in triglycerides. The low ratio of acids to unsaponifiables of this aspen wood, especially in the bottom stemwood, could probably have a negative effect on pitch problems. Small amounts of oligomeric or polymeric material with higher molar mass than the triglycerides were present only in bark.