2D-NMR (HSQC) difference spectra between specifically 13C-enriched and unenriched protolignin of Ginkgo biloba obtained in the solution state of whole cell wall material
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Noritsugu Terashima
Abstract
In the structural analysis of lignins by 13C-NMR, signal overlap limits definitive assignment and accurate intensity measurement. Selective labeling by 13C-enrichment of a specific carbon in lignin enhances its signal intensity in the spectrum. Further enhancement of the specifically labeled carbons can be realized via difference spectra created from the enriched and unenriched samples. Difference 2D 13C-1H correlation (HSQC) NMR spectra, derived from the spectra of specifically 13C-enriched lignin model polymers (so-called dehydrogenation polymers) and their unenriched counterparts, take advantage of the enhanced dispersion afforded by both 13C and 1H chemical shifts, diminishing the difficulties arising from the signal-overlap problem and aiding in definitive signal assignments. In this research, protolignin in xylem cell walls was specifically 13C-enriched at all of the individual phenylpropanoid side-chain carbons by feeding 13C-enriched coniferins to growing stems of Ginkgo biloba. The whole xylem fractions containing 13C-enriched and unenriched protolignins were dissolved in a mixture of N-methylimidazole and DMSO, and then acetylated. Solution state 2D-NMR (HSQC) spectra of the acetylated whole cell wall were acquired. Difference spectra between the walls containing 13C-enriched and unenriched lignins afforded simplified 2D spectra in which well-separated signals were assigned exclusively to the specifically enriched carbons. This novel NMR technique provides a useful tool for elucidation of entire protolignin in the cell wall of ginkgo xylem.
©2009 by Walter de Gruyter Berlin New York
Articles in the same Issue
- Original Papers
- 2D-NMR (HSQC) difference spectra between specifically 13C-enriched and unenriched protolignin of Ginkgo biloba obtained in the solution state of whole cell wall material
- Colour in thermally modified wood of beech, Norway spruce and Scots pine. Part 1: Colour evolution and colour changes
- Colour in thermally modified wood of beech, Norway spruce and Scots pine. Part 2: Property predictions from colour changes
- The relationship found between fibre length and viscosity of three different commercial kraft pulps
- High-yield kraft pulping of Eucalyptus grandis Hill ex Maiden biotreated by Ceriporiopsis subvermispora under two different culture conditions
- Analysis of microwave vs. thermally assisted grafting of poly(methyl-vinyl ether co-maleic acid)-polyethylene glycol to birch kraft pulp
- Selective enzyme impregnation of chips to reduce specific refining energy in alkaline peroxide mechanical pulping
- Radical chain reactions in pyrolytic cleavage of the ether linkages of lignin model dimers and a trimer
- Quantitative chemical indicators to assess the gradation of compression wood
- Comparison of mechanical properties of thermally modified wood at growth ring and cell wall level by means of instrumented indentation tests
- Revisiting the transition between juvenile and mature wood: a comparison of fibre length, microfibril angle and relative wood density in lodgepole pine
- Characterization of the wood quality of pernambuco (Caesalpinia echinata Lam) by measurements of density, extractives content, microfibril angle, stiffness, color, and NIR spectroscopy
- An improved drying model for highly-impermeable hardwoods
- Neutron attenuation coefficients for non-invasive quantification of wood properties
- Topochemical investigations of cell walls in developing xylem of beech (Fagus sylvatica L.)
- Effects of substrate on laboratory spalting of sugar maple
- Short Notes
- Apigenin derivatives from Paulownia tomentosa Steud. var. tomentosa stem barks
- Forming limits for the bulk forming of solid wood
- Meetings
- Meetings
Articles in the same Issue
- Original Papers
- 2D-NMR (HSQC) difference spectra between specifically 13C-enriched and unenriched protolignin of Ginkgo biloba obtained in the solution state of whole cell wall material
- Colour in thermally modified wood of beech, Norway spruce and Scots pine. Part 1: Colour evolution and colour changes
- Colour in thermally modified wood of beech, Norway spruce and Scots pine. Part 2: Property predictions from colour changes
- The relationship found between fibre length and viscosity of three different commercial kraft pulps
- High-yield kraft pulping of Eucalyptus grandis Hill ex Maiden biotreated by Ceriporiopsis subvermispora under two different culture conditions
- Analysis of microwave vs. thermally assisted grafting of poly(methyl-vinyl ether co-maleic acid)-polyethylene glycol to birch kraft pulp
- Selective enzyme impregnation of chips to reduce specific refining energy in alkaline peroxide mechanical pulping
- Radical chain reactions in pyrolytic cleavage of the ether linkages of lignin model dimers and a trimer
- Quantitative chemical indicators to assess the gradation of compression wood
- Comparison of mechanical properties of thermally modified wood at growth ring and cell wall level by means of instrumented indentation tests
- Revisiting the transition between juvenile and mature wood: a comparison of fibre length, microfibril angle and relative wood density in lodgepole pine
- Characterization of the wood quality of pernambuco (Caesalpinia echinata Lam) by measurements of density, extractives content, microfibril angle, stiffness, color, and NIR spectroscopy
- An improved drying model for highly-impermeable hardwoods
- Neutron attenuation coefficients for non-invasive quantification of wood properties
- Topochemical investigations of cell walls in developing xylem of beech (Fagus sylvatica L.)
- Effects of substrate on laboratory spalting of sugar maple
- Short Notes
- Apigenin derivatives from Paulownia tomentosa Steud. var. tomentosa stem barks
- Forming limits for the bulk forming of solid wood
- Meetings
- Meetings
