Characterization of the Polyphenolics Related to the Colour of Western Red Cedar (Thuja plicata Donn) Heartwood
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C. Ingemar Johansson
Summary
Three quarters of the western red cedar's heartwood colour is due to a polymeric material easily isolated by methanol extraction. The nature of this polymer has not been fully investigated and published information is contradictory. Our initial examination of the coloured polymer by pyrolysis-gas chromatography, combined with mass spectrometry, indicated that the polymer was guaiacyl in nature and thus similar to softwood lignin. However, analysis by infrared spectroscopy indicated the presence of both lignin and lignan like moieties. To clarify this issue a more detailed analysis was conducted using nuclear magnetic resonance spectroscopy (1H NMR, 31P NMR, 13C NMR). Analysis of the spectra and comparison with the spectra of plicatic acid and a product from mild acid treatment of plicatic acid, indicated that the polymeric fraction was derived almost entirely from lignans. During polymer formation, the highly reactive pyrocatechol moiety in the plicatic acid is destroyed, leaving a guaiacyl-like polymer. The reaction mechanism appears to proceed via an ortho-quinone intermediate followed by polymerization.
Copyright © 2000 by Walter de Gruyter GmbH & Co. KG
Articles in the same Issue
- Molecular Methods for the Characterization and Identification of the Dry Rot Fungus Serpula lacrymans
- Use of Soft Rot Fungi for Studies on the Microstructure of Kapok (Ceiba pentandra (L.) Gaertn.) Fibre Cell Walls
- Ultrastructural Changes in the Compound Middle Lamella of Pinus thunbergii During Lignification and Lignin Removal
- Comparison of the Antifungal Activity of Cadinane Skeletal Sesquiterpenoids from Taiwania (Taiwania cryptomerioides Hayata) Heartwood
- Characterization of the Polyphenolics Related to the Colour of Western Red Cedar (Thuja plicata Donn) Heartwood
- Influence of Botanical Species and Geographical Origin on the Content of Low Molecular Weight Phenolic Compounds of Woods Used in Portuguese Cooperage
- Effect of Oxygen Pressure on the Oxidation of Syringyl Alcohol Initiated by Manganese(III) Acetate
- Potential Catalysts for the Acetylation of Wood
- Quantification of Muconic Acid-Type Structures in High Molecular Weight Material from Bleach Plant Effluents
- The Effects of the Order of Chemical Addition on the Peroxide Bleaching of an Oxygen-Delignified Softwood Kraft Pulp
- Effects of Thermo-Hydro-Mechanical Treatment on the Structure and Properties of Wood
- Improvement of Heartwood Color of Black-Colored Sugi (Cryptomeria japonica D. Don) by UV Irradiation after Smoke Heating
- Analysis of the Wood Sorption Isotherm Using the Theory of Micropore Volume Filling
- Acoustic Emission Generated upon Mechano-Sorptive Creep of Wood Bent Across to the Grain under Asymmetrical Moistening
- Experimental Data Correction of the Dynamic Elastic Moduli, Velocity and Density of Solid Wood as a Function of Moisture Content above the Fiber Saturation Point
- Contractive Force and Transformation of Microfibril with Aqueous Sodium Hydroxide Solution for Wood
- Dielectric Relaxation Based on Adsorbed Water in Wood Cell Wall under Non-Equilibrium State. 1
- Stabilizing Effect of Chromated Salt Treatment on the Green Color of Ma Bamboo (Dendrocalamus latiflorus)
- Microwave-Enhanced Transport of Chemicals into Green Wood under Low-Headspace Conditions
- Personalia: Günther Stegmann in memoriam
Articles in the same Issue
- Molecular Methods for the Characterization and Identification of the Dry Rot Fungus Serpula lacrymans
- Use of Soft Rot Fungi for Studies on the Microstructure of Kapok (Ceiba pentandra (L.) Gaertn.) Fibre Cell Walls
- Ultrastructural Changes in the Compound Middle Lamella of Pinus thunbergii During Lignification and Lignin Removal
- Comparison of the Antifungal Activity of Cadinane Skeletal Sesquiterpenoids from Taiwania (Taiwania cryptomerioides Hayata) Heartwood
- Characterization of the Polyphenolics Related to the Colour of Western Red Cedar (Thuja plicata Donn) Heartwood
- Influence of Botanical Species and Geographical Origin on the Content of Low Molecular Weight Phenolic Compounds of Woods Used in Portuguese Cooperage
- Effect of Oxygen Pressure on the Oxidation of Syringyl Alcohol Initiated by Manganese(III) Acetate
- Potential Catalysts for the Acetylation of Wood
- Quantification of Muconic Acid-Type Structures in High Molecular Weight Material from Bleach Plant Effluents
- The Effects of the Order of Chemical Addition on the Peroxide Bleaching of an Oxygen-Delignified Softwood Kraft Pulp
- Effects of Thermo-Hydro-Mechanical Treatment on the Structure and Properties of Wood
- Improvement of Heartwood Color of Black-Colored Sugi (Cryptomeria japonica D. Don) by UV Irradiation after Smoke Heating
- Analysis of the Wood Sorption Isotherm Using the Theory of Micropore Volume Filling
- Acoustic Emission Generated upon Mechano-Sorptive Creep of Wood Bent Across to the Grain under Asymmetrical Moistening
- Experimental Data Correction of the Dynamic Elastic Moduli, Velocity and Density of Solid Wood as a Function of Moisture Content above the Fiber Saturation Point
- Contractive Force and Transformation of Microfibril with Aqueous Sodium Hydroxide Solution for Wood
- Dielectric Relaxation Based on Adsorbed Water in Wood Cell Wall under Non-Equilibrium State. 1
- Stabilizing Effect of Chromated Salt Treatment on the Green Color of Ma Bamboo (Dendrocalamus latiflorus)
- Microwave-Enhanced Transport of Chemicals into Green Wood under Low-Headspace Conditions
- Personalia: Günther Stegmann in memoriam
