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PubMed · 16768426

Linear aliphatic dimeric esters from cork suberin.

José Graça·Sara Santos
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Abstract

Cork suberin was partially depolymerized by methanolysis catalyzed by calcium hydroxide. Analysis by GC-MS of the methanolysate showed suberin monomers, including glycerol and long-chain alpha,omega-diacids and omega-hydroxyacids. ESI-MS analysis of the methanolysate showed, besides the aliphatic monomers, suberin oligomers, including linear dimeric esters of alpha,omega-diacids and omega-hydroxyacids. Two types of dimeric esters were identified: a alpha,omega-diacid linked to a omega-hydroxyacid and two inter-linked omega-hydroxyacids. The alpha,omega-diacids and omega-hydroxyacids found as monomer residues in the dimeric esters were mainly the C18 monomers with midchain substituents. The identification of these dimeric esters was based in their CID-MS/MS spectra and confirmed after synthesis of model compounds. The occurrence of inter-esterified long-chain monomers in suberin brings a new insight in the understanding of the polyester structure of this biopolymer.

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DimerizationEstersLipidsMembrane LipidsMolecular StructureSensitivity and SpecificitySpectrometry, Mass, Electrospray IonizationTreesJournal ArticleResearch Support, Non-U.S. Gov't

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José Graça, Sara Santos. 2006. Linear aliphatic dimeric esters from cork suberin.. https://doi.org/10.1021/bm060174u

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