New Preparations of Lignin Polymer Models under Conditions that Approximate Cell Wall Lignification. II. Structural Characterization of the Models by Thioacidolysis

Structural Characterization and Iron(III) Binding Ability of Dimeric and Polymeric Lignin Models

“…The carbonyl signals of acetyl were observed as three peaks corresponding to primary, secondary, and phenolic alcohol moieties respectively at 171.0, 170.8, and 169.1 ppm. Owing to a great number of scans (50,000) with a relaxation delay of 4 s, it was possible to relatively quantify these functional groups (20)(21)(22): about 14% of phenolic alcohol, 28% of primary alcohol, and 57% of secondary alcohol. Since the β-6, β-5, and 5-5 structures do not contain secondary hydroxy1 groups, a high content of this type of alcohol can indicate a great abundance of β-O-4 structure.…”

Lignin Chemistry: Biosynthetic Study and Structural Characterisation of Coniferyl Alcohol Oligomers Formed In Vitro in a Micellar Environment

“…They studied the b-glucosidase/ peroxidase-triggered polymerisation of coniferin (coniferyl alcohol glucoside) [10,11] and coniferyl alcohol polymerisation in the presence of pectin. [12,13] In both cases it has been demonstrated that the structures of the obtained polymers approximate those of native lignins more closely than the pure coniferyl lignin model, whereas the latter leads to the isolation of pectin-DHP complex.…”

Lignin Formation in Plants. The Dilemma of Linkage Specificity

“…2). In native lignins, 8-O-4-linkages are the most abundant, whereas for lignins formed in vitro by mixing coniferyl alcohol, hydrogen peroxide, and peroxidase, higher percentages of 8-8-and 8-5-linkages are found (Nimz and Ludemann, 1976;Terashima et al, 1996;Chen, 1998). How is this apparent specificity in chemical bonds between lignin subunits controlled?…”