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Direct evidence for ? ether linkage between lignin and carbohydrates in wood cell walls.

ABSTRACT: Cross-linking between lignin and polysaccharide in plant cell-wall determines physical, chemical, and biological features of lignocellulosic biomass. Since Erdmann's first report in 1866, numerous studies have suggested the presence of a bond between hemicelluloses and lignin; however, no clear evidence for this interaction has been reported. We describe the first direct proof of covalent bonding between plant cell-wall polysaccharides and lignin. Nuclear magnetic resonance spectroscopy was used to observe the long-range correlations through an ?-ether bond between lignin and the primary hydroxyl group of a mannose residue in glucomannan. Complete signal assignment of the cognate structural units was also achieved. Thus, we identified lignin-carbohydrate bonds by complete connectivity analysis from the phenylpropane unit to the carbohydrate moiety.

SUBMITTER: Nishimura H

PROVIDER: S-EPMC5916878 | biostudies-other | 2018 Apr

REPOSITORIES: biostudies-other

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Direct evidence for α ether linkage between lignin and carbohydrates in wood cell walls.

Nishimura Hiroshi H Kamiya Akihiro A Nagata Takashi T Katahira Masato M Watanabe Takashi T

Scientific reports 20180425 1

Cross-linking between lignin and polysaccharide in plant cell-wall determines physical, chemical, and biological features of lignocellulosic biomass. Since Erdmann's first report in 1866, numerous studies have suggested the presence of a bond between hemicelluloses and lignin; however, no clear evidence for this interaction has been reported. We describe the first direct proof of covalent bonding between plant cell-wall polysaccharides and lignin. Nuclear magnetic resonance spectroscopy was used ...[more]

PMID: 29695732

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