XVI International Botanical Congess
Primary plant tissues are covered by cuticles, i.e. a polymeric cutin matrix and cuticular waxes. They limit water loss across the large surface which plants expose to the atmosphere. In the cuticular waxes of Prunus laurocerasus leaves very-long chain alkanes, fatty acids, aldehydes, primary alcohols, acetates and triterpenoids were identified. Protocols for the mechanical removal of surface waxes were devised and evaluated. With the most selective of these methods 1/5 of the (adaxial) wax load could be removed before a physically resistant boundary was reached. Compounds thus obtained are interpreted as 'epicuticular waxes' with respect to their localization in a layer on the surface of the cutin matrix. They consisted entirely of aliphatics, while the remaining intracuticular waxes comprised 63% of triterpenoids.