Guaiacyl lignin

Table I. Use of Doubly labeled Guaiacyl Lignin Precursors in Lignin Biosynthesis Studies...

Figure 1. Formation of guaiacyl lignin and lignin-carbohydrate complexes (LCC) via dehydrogenative polymerization of coniferyl alcohol.

In normal softwood lignin, usually referred to as guaiacyl lignin, the structural elements are derived principally from coniferyl alcohol, (1) (more than 95% of the total number of structural units), with the remainder consisting mainly of p-coumaryl alcohol-type units (Fig. 1.1, unit 2) and trace amounts of sinapyl alcohol-derived units (Fig. 1.1, unit 13). 

Assuming the total X-ray counts of Br-Ka is the sum of the X-ray intensities from the brominated syringyl and guaiacyl lignins, then... 

From Eqs. (2) and (3), the concentration of the syringyl and guaiacyl lignins in the wood cells are calculated from the expressions... 

Wolter KE, Harkin JM, Kirk TK (1974) Guaiacyl lignin associated with vessels in aspen callus cultures Physiol Plant 31 140-143... 

Yasuda S, Ota K (1987) Chemical structures of sulfuric acid lignin X Reaction of syringylglycerol-/f-syringyl ether and condensation of synngyl nucleus with guaiacyl lignin model compounds m sulfuric acid Holzforschung 41 59-65... 

Qualitatively, it has been demonstrated by Meshitsuka and Nakano (1985) that guaiacyl lignin in the middle lamella region is more condensed than the lignin in the secondary wall region Quantitatively, this has been confirmed by applying the NE method to secondary wall- and middle lamella-enriched... 

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