Chemical composition of the epicuticular wax from the fruits ofEucalyptus globulus

The chemical composition of the epicuticular wax from the fruits of Eucalyptus globulus was studied by GC-MS before and after alkaline hydrolysis. The wax had two main components, ursolic acid and tritriacontan-16,18-dione, together with several other triterpenic acids. After alkaline hydrolysis, a large increase in the amounts of triterpenic acids and fatty acids (particularly in hexadecanoic acid) was observed, suggesting that these components were present predominantly in esteried forms in the fruit wax. Six compounds were isolated from the fruits by preparative chromatography, and were identied as 8-desmethyleucalyptin, sesamin, tritriacontan-16,18-dione, ursolic acid, 3β-hydroxyurs-11-en-13β(28)-olide (ursolic acid lactone) and 3β,11α-dihydroxyurs-12-en-28-oic acid, the latter of which was identied for the rst time. Copyright © 2005 John Wiley & Sons, Ltd.