Topic 13.3

Detailed Chemical Structure of a Portion of a Lignin Molecule

Web Figure 13.3.A Partial structure of a hypothetical lignin molecule from European beech (Fagus sylvatica ). The phenylpropanoid units that make up lignin are not linked in a simple, repeating way. The lignin of beech contains units derived from coniferyl alcohol, sinapyl alcohol, and para-coumaryl alcohol in the approximate ratio 100:70:7 and is typical of angiosperm lignin. Gymnosperm lignin contains relatively fewer sinapyl alcohol units. (After Nimz 1974.) (Click image to enlarge.)