SUBERIN COMPOSITION OF REPRODUCTION CORK FROM QUERCUS-SUBER

The monomeric composition of suberins from Spanish Quercus suber was d etermined by gas chromatography/mass spectrometry in the product of de polymerization of free extractives cork with sodium methoxide-methanol . 1-Alkanols (C-20-C-26)(1.8-6.4%), alkanoic acids (C-20-C-24)(2.2-8.1 %), alpha,omega-alkanedioic acids (C-16-C-24)(6.1-10.2%) and omega-hyd roxy-alkanoic acids (C-20-C-26, being C-22 and C-24 the most abundant) (28.7-37.3%) are identified. The erythro- and threo-9,10-dihydroxyocta decanedioic (5.4-7.5%), erythro- and threo-9,10,18-trihydroxyoctadecan oic (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 phenol ic component of suberin. The studied samples differ in the relative pr oportion of the different monomers.