Chemical Composition and Ultrastructure of Suberin from Hollow Heart Tissue of Potato Tubers (Solanum tuberosum).

The disorder of potato tubers (Solanum tuberosum var. Russet Burbank) called "hollow heart" is manifested by the occurrence of hollow regions in internal parts of the tuber. The structure and composition of the suberin from the tissue lining of these internal cavities were determined by gas chromatography and mass spectrometry of the LiAlH(4)-hydrogenolysis products. Identification of octadecene-1,18-diol as the major component and the presence of hexadecane-1,16-diol and very long chain (>C(18)) alcohols in the hydrogenolysate showed that the suberin lining the internal cavities is quite similar to that found in the periderm of external wounds and the natural skin. Electron microscopic examination showed similar lamellar structure for the suberin of hollow heart, external wound periderm, and the natural skin of potato tubers. The results show that suberin can develop in a tissue which is not exposed to the external environment.