Solid-state 13C nuclear magnetic resonance characterization of cellulose in the cell walls of Arabidopsis thaliana leaves.

摘要

Solid-state 13C nuclear magnetic resonance was used to characterize the molecular ordering of cellulose in a cell-wall preparation containing mostly the primary walls obtained from the leaves of Arabidopsis thaliana. Proton and 13C spin relaxation time constants indicated that the cellulose was in a crystalline rather than a paracrystalline state or amorphous state. Cellulose chains were distributed between the interiors (40%) and surfaces (60%) of crystallites, which is consistent with crystallitecross-sectional dimensions of about 3 nm. Digital resolution enhancement revealed signals indicative of triclinic and monoclinic crystalline forms of cellulose mixed in similar proportions. Of the 5 nuclear spin relaxation processes used, proton rotating-frame relaxation provided the clearest distinction between cellulose and other cell-wall components for the purposes of editing solid-state 13C nuclear magnetic resonance spectra.