Suberin Composition of Reproduction Cork fromQuercus suber

The monomeric composition of suberins from Spanish Quercus suber was determined by gas chromatography/mass spectrometry in the product of depolymerization of free extractives cork with sodium methoxide-methanol. 1-Alkanols (C20-C26)(1.8-6.4 %), alkanoic acids (C20-C24)(2.2-8.1 %), α,ω-alkanedioic acids (C16-C24)(6.1-10.2 %) and ω-hydroxy-alkanoic acids (C20-C26, being C22 and C24 the most abundant)(28.7-37.3 %) are identified. The erythro- and threo-9,10-dihydroxyoctadecanedioic (5.4-7.5 %), erythro- and threo-9,10,18-trihydroxyoctadecanoic (7.6-11.8 %), 9,10-epoxy-18-hydroxyoctadecanoic (1.2-3.1 %) and 9,10-epoxy-octadecanodioic acids (1.0-4.4 %) and the unsaturated 18-hydroxy-9-octadecenoic (8.1-11.5 %) and 9-octadecenedioic (1.5-2.4 %) acids are also important components. Ferulic acid (5.3-9.1 %) is the main phenolic component of suberin. The studied samples differ in the relative proportion of the different monomers.