Journal Article10.1515/HFSG.1981.35.1.16
Carbon-13 NMR Spectra of Lignins, 8. Structural Differences between Lignins of Hardwoods, Softwoods, Grasses and Compression Wood
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TL;DR: The carbon-13 NMR Spectra of four acetylated hardwood MWLs (Acer platanoides, Carpinus betulus, Prunus avium and Quercus robur) were compared with those of dehydrogenation polymers (DHPs) from p-coumaryl alcohol (H- DHP), a Co-DHP obtained from an equimolar mixture of guaiacyl-(G), syringyl-(S) and p-hydroxyphenylpropane (H) units.
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Abstract: The carbon-13 NMR Spectra of four acetylated hardwood MWLs (Acer platanoides, Carpinus betulus, Prunus avium and Quercus robur), two acetylated grass MWLs (Bambusa tulda, Triticum aestivum), one nonacetylated grass MWL (Zea canina) and one acetylated compression wood MWL (Larix leptolepis) are compared with those of dehydrogenation polymers (DHPs) from p-coumaryl alcohol (H— DHP), a Co-DHP obtained from an equimolar mixture of p-coumaryl, coniferyl and sinapyl alcohols (GHS-DHP), acetylated spruce MWL and nonacetylated beech MWL. The spectra reveal characteristic Structural features of the lignins, justifying their classification either äs G-lignins (from softwoods), GS-lignins (from hardwoods), GSH-lignins (from grasses) or GH-lignins (from compression wood), depending on their composition of guaiacyl-(G), syringyl-(S) and p-hydroxyphenylpropane (H) units.
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Citations
Lignins: Natural polymers from oxidative coupling of 4-hydroxyphenyl- propanoids
John Ralph,Knut Lundquist,Gösta Brunow,Fachuang Lu,Hoon Kim,Paul F. Schatz,Jane M. Marita,Ronald D. Hatfield,Sally A. Ralph,Jorgen Holst Christensen,Wout Boerjan +10 more
TL;DR: A recent challenge to the currently accepted theory of chemically controlled lignification, attempting to bring lignin into line with more organized biopolymers such as proteins, is logically inconsistent with the most basic details of the structure.
Abiotic and Biotic Stresses and Changes in the Lignin Content and Composition in Plants
Jullyana Cristina Magalhães Silva Moura,Cesar Augusto Valencise Bonine,Juliana de Oliveira Fernandes Viana,Marcelo Carnier Dornelas,Paulo Mazzafera +4 more
TL;DR: In this paper, a review focuses on recent literature reporting on the main types of abiotic and biotic stresses that alter the biosynthesis of lignin in plants and how a stressor modulates expression of the genes related with ligninsynthesis.
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References
•Journal Article
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TL;DR: In this paper, it was found that by grinding wood, dispersed in a non-swelling liquid, in a vibrational ball mill, it is possible to extract 50per thousand or more of the lignin from spruce (Picea excelsa ), providing the charge to the mill is small enough.
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Comparative Studies on Cellulolytic Enzyme Lignin and Milled Wood Lignin of Sweetgum and Spruce
TL;DR: In this paper, the same batch of ball milled sapwood of sweetgum and Norway spruce was used to isolate MWL and Cellulolytic Enzyme Lignin (CEL).
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The Location of Guaiacyl and Syringyl Lignins in Birch Xylem Tissue
B. J. Fergus,D. A. I. Goring +1 more
TL;DR: In this article, it was shown that the lignin associated with the vessel secondary wall and middle lamella of birch xylem is composed predominandy of guaiacylpropane units.
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The abnormal lignins produced by the brown-midrib mutants of maize. i. the brown-midrib-1 mutant.
Joseph Kuć,Oliver E. Nelson +1 more
TL;DR: It is suggested that the primary action of the non-mutant ( Bm 1 ) gene at the bm 1 locus is to exert a measure of control over the manner of incorporation of the phenolic building blocks into the lignin polymer.
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