Figure 2.

2D HSQC NMR spectra of enzyme lignins (EL) of leaf base tissue. A, Outer tissue region. B, Inner tissue region. C, Cell wall components detected by HSQC NMR. The pCA, along with traces of FA, are present in the outer tissue region, whereas BA is visible only in the inner tissue region, and pBA is found throughout the leaf base. Tabulated values are from contour volume integrals only and are on an S + G = 100 basis. Note that the mobile end groups on the polymer (including BA, pBA, pCA, and FA) have integrals that overrepresent their concentrations relative to internal units in these spectra (Mansfield et al., 2012).