CORK SUBERIN AS A NEW SOURCE OF CHEMICALS - 1 - ISOLATION AND CHEMICAL CHARACTERIZATION OF ITS COMPOSITION

Extractive-free cork from Quercus suber L. was submitted to a solvolys is treatment with methanolic NaOH which yielded 37% (o.d. cork) of sub erin. This mixture of compounds was thoroughly characterized by FTIR, H-1- and C-13-NMR, gas chromatography coupled with mass spectrometric (GC-MS) analysis, vapour pressure osmometry (VPO), mass spectrography (MS) and gel permeation chromatography (GPC). After derivatization, th e main components of the volatile fraction, representing less than hal f of the total, were found to be omega-hydroxymonocarboxylates, alpha, omega-dicarboxylates, simple alkanoates and 1-alkanols, all with chain lengths ranging from C16 to C24. A second fraction, with an average m olecular weight about three times higher, was detected by VPO, MS and GPC. The presence of this important fraction in cork suberin had not b een recognized in earlier studies. Both fractions constitute interesti ng precursors for the elaboration of new materials. (C) 1998 Elsevier Science B.V. All rights reserved.