Ester Groups in Lignin

Highly Decorated Lignins in Leaf Tissues of the Canary Island Date Palm Phoenix canariensis

“…p-coumarate) from sugarcane (Saccharum spp.) lignins by mild alkaline hydrolysis (Smith, 1955a). Smith (1955b) also showed that p-hydroxybenzoate (pBA) was linked through ester bonds to the lignin of aspen (Populus temula).…”

Comparison of Lignin-Like Polymers Produced Peroxidatively by Cinnamic Acid Derivatives in Leaf Sections of Phleum

“…Similar peaks, however, have been found in other grasses, i.e., in native lignin preparations from bagasse and wheat (13,14). Absorption above 310 mu could be clue to the presence of (louble bonds in the side chains in conjugation with free phenolic nuclei, indicating less highly polymerized molecules or ester linkages (12). Pre Besides the problem of the non-physiological conditions necessary to produce these lignin-like polymers (14), and the lignification in some cases of nonvascular tissue, further difficulties in the interpretation of these results may be clue to confusion concerning the nature of lignin.…”

Comparison of Lignin-like Products Found Naturally or Induced in Tissues of Phleum, Elodea, and Coleus, and in a Paper Perioxidase System

“…In spite of the inability of saponification or of esterase preparations to release significant amounts of ferulic acid from any of these lignin products, it is still possible to attribute the peak in the difference spectrum of the products soluble in NaHCO3 to ester linkages (11,18). For instance, the C6-C3 acids may still be attached to other units in nonester but alkali sensitive linkages.…”

“…Acid precipitation of lignin products in alkaline extracts of induced and natural lignins likewise produced an array of different spectra (fig 8) Most workers assume that the hydroxycinnamic acids associated with lignin residues are linked as esters to already formed lignin (11,18). Natural and induced lignins were saponified or hydrolyzed by esterases to detect such ester linkages.…”