| Abstract
| - Suberin in extractive-free potato periderm amounts to ∼25% determined by NaOCH3 methanolysis.Monomeric composition is characterized by glycerol (20% of monomers), long-chain α,ω-diacids,ω-hydroxyacids, alkanoic acids, and alkan-1-ols, with predominance of octadec-9-enodioic acid and18-hydroxyoctadec-9-enoic acid (39 and 15% of long-chain monomers, respectively). Aromatichydroxycinnamyl monomers were also present (<1%). Partial depolymerization of potato peridermsuberin using a Ca(OH)2-catalyzed methanolysis solubilized ∼10% of suberin aliphatics. GC-MSanalysis showed the presence of monomers, dimers, and trimers (87, 12, and 1% of identifiedcompounds, respectively). A total of 26 dimers were identified by EIMS: monoacylglyceryl esters ofα,ω-diacids, ω-hydroxyacids, and alkanoic acids (with predominance of the 1- and 2-isomers of themonoacylglyceryl ester of the octadec-9-enodioic acid), as well as feruloyl esters of ω-hydroxyacidsand alkan-1-ols and a small quantity of a monoferuloylglycerol. Following a discussion of suberinmacromolecular structure, it is proposed that in suberized cell walls, the polyaliphatic polymershave a three-dimensional development ensured by glycerol and exist independently from theassociated polyaromatics. Keywords: Suberin; Solanum tuberosum; potato periderm; monoacylglyceryl esters; feruloyl esters
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