| Abstract | The chemical composition of suberin was studied in cork planks fromthree different trees of Spanish Quercus suber at four different stages
of the industrial processing of first transformation: stripping (a),
first rest (b), boiling followed by open air rest (c1) and boiling
followed by store-room rest (c2). The monomeric composition was
determined by gas chromatography/mass spectrometry in the product of
depolymerization of the free of extractives cork with sodium
methoxide-methanol. The average concentrations of the main monomers
were: 1-alkanols (C-20-C-26) 4.17 %; alkanoic acids (C-20-C-26) 5.99
%; alpha, omega-alkanedioic acids (C-16-C-24) 6.20 %;
omega-hydroxy-alkanoic acids (C-20-C-26) 29.41 %; erythro- and threo-9,
10-dihydroxyoctadecanedioic acids 6.76 %, erythro- and
threo-9,10,18-trihydroxyoctadecanoic acids 9.50 %,
9,10-epoxy-18-hydroxyoctadecanoic acid 2.72 % and
9,10-epoxy-octadecanedioic acid 2.93 % and ferulic acid 5.05 %.
Significant differences were observed between samples taken at the
stripping and after boiling with store room rest, and both groups of
samples differed from those picked after the other two processing
stages. Ten components were selected as providing the greatest
discrimination among stages: 9-octadecenedioic,
18-hydroxy-9-octadecenoic, eicosanedioic and
9,10-epoxy-18-hydroxy-octadecanoic acids, tetracosanol, and five
unidentified components.
|
