C nuclear magnetic resonance study of suberized potato cell wall.

High-resolution, solid-state (13)C nuclear magnetic resonance (NMR) spectra are reported for suberized cell wall from potatoes (Solanum tuberosum L.). Through experiments combining the techniques of cross polarization and magic-angle spinning, we verified that suberin, like cutin, is a polyester and demonstrated that it also has phenylpropanoid groups characteristic of lignin. Roughly 50% of the suberized material consists of cell-wall polymers; aromatics and other unsaturated linkages outnumber methylene groups 2:1. In conjunction with traditional direct-polarization NMR results, these experiments provide support for prior suggestions that suberin and cell-wall components are chemically bonded via aromatic groups.