The Composition of the Lipid Constituents of Ilex aquifolium L. {Aquifoliaceae) in Relation to the Age of the Leaf. I. The Leaf Wax.

With increasing age of the leaf the chloroform-soluble part of the surface wax changes from a rather apolar composition largely constituted of a homologous series of hexyl esters of high molecular, saturated fatty acids (C22\3-C32) to a more polar composition with the triterpenol a-amyrin as the major component. Saturated long-chain hydrocarbons start to accumulate during leaf extension, whereas the major triterpenol accumulation occurs on full-grown leaves from the end of the first year of development. Minor concentrations of triterpenes are present on very young leaves with β-amyrin and β-amyrone as major components instead of the corresponding α-compounds.