A combined view on composition, molecular structure, and micromechanics of fungal degraded softwood
-
Leopold Wagner
,
Thomas K. Bader
Abstract
Fungal decay alters the composition, microstructure, and mechanical properties of wood cell walls. To understand better the structure-function relationships during fungal decay, selected annual rings of fungal deteriorated Scots pine sapwood were analyzed in terms of their composition, microstructure, and micromechanical properties. The datasets were acquired separately for earlywood and latewood concerning the S2 cell wall layer and the cell corner middle lamella (CCML) and analyzed by means of principal component analysis and partial least squares regression analysis. Links between cell wall stiffness and hardness and the composition and microstructure could be established. Increased mechanical properties in the CCML, as obtained by nanoindentation, were correlated to the degradation of pectins. In the S2 layer, the altered data were related to the degradation of hemicelluloses and lignin modification during fungal decay.
Acknowledgments
The authors acknowledge the Vienna University of Technology for financial support via the “Innovative Project 2010: Microstructural and chemical characterization of softwood degradation by basidiomycetes and its effects on the mechanical behavior”. L.W. acknowledges COST Action FP0802 for the approval and financial support of a short-term scientific mission (STSM) to visit the Max-Planck Institute of Colloids and Interfaces for the majority of the WAXS experiments and Dr. Michaela Eder for hosting the STSM. K.F. acknowledges the support of the Austrian Science Fund (FWF Project V117-N17).
Appendix: Compositional, microstructural, and micromechanical data
Chemical composition of EW and LW samples.
| Sample | Lig (%) | Ara (%) | Xyl (%) | Rha (%) | Man (%) | Gal (%) | Acc. Glu (%) | GalUA (%) | GlcUA (%) |
|---|---|---|---|---|---|---|---|---|---|
| REF. 1 | |||||||||
| EW | 26.9 | 2.5 | 6.2 | 0.4 | 11.5 | 2.8 | 3.7 | 2.4 | 0.6 |
| LW | 26.9 | 1.7 | 4.3 | 0.3 | 14.5 | 2.5 | 4.5 | 1.4 | 0.5 |
| REF. 2 | |||||||||
| EW | 26.9 | 1.8 | 6.0 | 0.6 | 10.9 | 2.4 | 3.9 | 1.8 | 0.3 |
| LW | 25.5 | 1.4 | 4.8 | 0.3 | 16.3 | 2.1 | 5.3 | 1.2 | 0.5 |
| BR 2.1 | |||||||||
| EW | 26.3 | 1.6 | 4.5 | 0.3 | 7.3 | 1.7 | 2.6 | 1.0 | 0.6 |
| LW | 23.7 | 1.7 | 5.8 | 0.2 | 15.4 | 2.2 | 4.8 | 1.2 | 0.7 |
| BR 2.2 | |||||||||
| EW | 26.7 | 2.0 | 7.6 | 0.4 | 10.5 | 2.7 | 4.3 | 1.5 | 0.5 |
| LW | 24.3 | 1.7 | 6.7 | 0.3 | 13.2 | 2.2 | 4.6 | 1.2 | 0.5 |
| BR 2.3 | |||||||||
| EW | 27.6 | 1.5 | 5.6 | 0.3 | 16.7 | 1.9 | 4.7 | 0.9 | 0.4 |
| LW | 25.9 | 1.5 | 5.5 | 0.3 | 15.5 | 3.3 | 4.7 | 1.1 | 0.4 |
| BR 4.1 | |||||||||
| EW | 28.9 | 1.1 | 4.7 | 0.2 | 8.0 | 1.2 | 6.7 | 0.8 | 0.5 |
| LW | 25.2 | 1.3 | 5.5 | 0.4 | 13.5 | 1.6 | 7.1 | 0.9 | 0.5 |
| BR 4.2 | |||||||||
| EW | 27.7 | 1.0 | 5.1 | 0.2 | 7.1 | 1.3 | 4.1 | 1.0 | 1.7 |
| LW | 26.3 | 1.4 | 6.5 | 0.3 | 11.9 | 1.8 | 5.7 | 0.9 | 0.6 |
| BR 4.3 | |||||||||
| EW | 26.3 | 1.6 | 6.5 | 0.3 | 12.8 | 2.0 | 5.1 | 1.3 | 0.4 |
| LW | 25.5 | 1.6 | 7.2 | 0.3 | 18.1 | 2.3 | 6.1 | 1.0 | 0.5 |
| BR 4.4 | |||||||||
| EW | 28.1 | 1.5 | 5.9 | 0.3 | 11.3 | 2.6 | 4.7 | 1.0 | 0.6 |
| LW | 26.1 | 1.3 | 4.5 | 0.2 | 10.5 | 3.1 | 4.1 | 0.7 | 0.3 |
| BR 6.1 | |||||||||
| EW | 27.6 | 1.4 | 5.4 | 0.3 | 9.1 | 1.6 | 7.6 | 1.0 | 1.3 |
| LW | 27.4 | 1.4 | 6.4 | 0.3 | 16.4 | 3.6 | 5.9 | 1.1 | 0.7 |
| BR 6.2 | |||||||||
| EW | 27.5 | 1.5 | 7.3 | 0.4 | 12.6 | 2.3 | 6.8 | 1.0 | 0.5 |
| LW | 25.2 | 1.2 | 5.7 | 0.2 | 9.7 | 1.5 | 5.3 | 0.7 | 0.5 |
| BR 6.3 | |||||||||
| EW | 27.3 | 1.2 | 4.3 | 0.2 | 11.3 | 2.0 | 4.8 | 1.1 | 0.6 |
| LW | 26.0 | 1.6 | 7.1 | 0.3 | 16.0 | 2.0 | 7.5 | 0.9 | 0.6 |
| BR 6.4 | |||||||||
| EW | 27.8 | 1.1 | 4.8 | 0.4 | 13.6 | 1.5 | 6.5 | 1.0 | 0.6 |
| LW | 26.8 | 1.2 | 5.6 | 0.4 | 9.5 | 1.6 | 6.2 | 0.9 | 0.6 |
| WR 2.1 | |||||||||
| EW | 26.1 | 1.7 | 5.9 | 0.4 | 13.4 | 2.4 | 4.8 | 2.0 | 0.5 |
| LW | 23.9 | 1.4 | 4.8 | 0.4 | 15.1 | 2.0 | 4.5 | 1.4 | 0.7 |
| WR 2.2 | |||||||||
| EW | 26.5 | 1.8 | 6.3 | 0.4 | 12.1 | 2.5 | 4.4 | 1.9 | 0.4 |
| LW | 23.3 | 1.6 | 5.4 | 0.3 | 14.4 | 2.2 | 4.6 | 1.5 | 0.6 |
| WR 2.3 | |||||||||
| EW | 27.2 | 1.8 | 5.6 | 0.2 | 16.2 | 2.3 | 5.4 | 1.5 | 0.6 |
| LW | 23.6 | 1.4 | 5.1 | 0.2 | 14.3 | 1.9 | 4.8 | 1.0 | 0.4 |
| WR 2.4 | |||||||||
| EW | 26.3 | 1.5 | 5.6 | 0.3 | 12.6 | 2.5 | 4.1 | 1.6 | 0.5 |
| LW | 23.6 | 1.4 | 5.5 | 0.3 | 15.4 | 3.9 | 4.1 | 1.4 | 0.5 |
| WR 6.1 | |||||||||
| EW | 23.6 | 1.7 | 7.4 | 0.5 | 13.7 | 2.3 | 5.8 | 1.8 | 0.6 |
| LW | 23.1 | 1.6 | 5.8 | 0.3 | 13.2 | 2.0 | 4.4 | 1.3 | 0.6 |
| WR 6.2 | |||||||||
| EW | 24.2 | 1.6 | 5.6 | 0.4 | 12.3 | 2.2 | 5.0 | 1.7 | 0.7 |
| LW | 22.6 | 1.2 | 4.2 | 0.3 | 14.2 | 1.9 | 4.9 | 1.2 | 0.5 |
| WR 6.3 | |||||||||
| EW | 24.3 | 2.4 | 6.8 | 0.3 | 10.1 | 2.7 | 4.3 | 2.7 | 1.0 |
| LW | 22.6 | 1.6 | 5.5 | 0.2 | 12.8 | 2.1 | 4.7 | 1.6 | 0.8 |
| WR 6.4 | |||||||||
| EW | 24.3 | 2.1 | 5.2 | 0.4 | 11.1 | 2.5 | 4.5 | 2.1 | 0.6 |
| LW | 22.7 | 1.8 | 5.2 | 0.3 | 12.0 | 2.2 | 4.3 | 1.3 | 0.5 |
| WR 6.5 | |||||||||
| EW | 24.1 | 1.2 | 4.3 | 0.3 | 10.4 | 1.7 | 3.9 | 1.4 | 1.2 |
| LW | 23.4 | 1.3 | 4.7 | 0.4 | 14.0 | 1.8 | 4.8 | 1.0 | 0.5 |
| WR 12.1 | |||||||||
| EW | 23.1 | 1.7 | 6.1 | 0.4 | 12.6 | 2.1 | 5.4 | 1.9 | 2.1 |
| LW | 21.9 | 1.2 | 4.2 | 0.3 | 17.1 | 1.8 | 5.7 | 1.3 | 0.4 |
| WR 12.2 | |||||||||
| EW | 24.3 | 1.1 | 4.6 | 0.3 | 10.3 | 1.5 | 4.3 | 1.4 | 1.5 |
| LW | 22.6 | 0.9 | 3.8 | 0.2 | 14.7 | 1.5 | 5.0 | 0.9 | 1.4 |
| WR 12.3 | |||||||||
| EW | 23.9 | 1.1 | 4.7 | 0.3 | 13.7 | 1.7 | 6.0 | 1.4 | 1.7 |
| LW | 22.1 | 0.9 | 4.6 | 0.3 | 16.9 | 1.5 | 6.3 | 1.1 | 1.9 |
| WR 12.4 | |||||||||
| EW | 23.3 | 1.3 | 5.0 | 0.3 | 9.9 | 2.8 | 3.9 | 2.2 | 1.2 |
| LW | 21.1 | 1.1 | 4.7 | 0.2 | 12.7 | 2.2 | 4.7 | 1.2 | 0.6 |
| WR 12.5 | |||||||||
| EW | 24.3 | 1.4 | 4.6 | 0.3 | 11.6 | 1.8 | 4.3 | 1.5 | 0.3 |
| LW | 21.4 | 1.1 | 3.6 | 0.3 | 14.5 | 1.6 | 4.4 | 1.1 | 0.4 |
Lig, lignin.
Indentation moduli (MS2), hardness (HS2), MFA and sample crystallinity (Cr) of EW and LW as well as indentation moduli (MCCML) and hardness (HCCML).
| Sample | Secondary wall (S2) | CCML | ||||
|---|---|---|---|---|---|---|
| MFA (°) | Cr (%) | M (GPa) | H (GPa) | M (GPa) | H (GPa) | |
| REF. 1 | ||||||
| EW | 11.6 | 31.7 | 0.38±0.02 | 16.10±1.62 | 6.23±0.29 | 0.30±0.02 |
| LW | 7.8 | 31.5 | 0.38±0.02 | 18.81±1.19 | ||
| REF. 2 | ||||||
| EW | 17.6 | 32.6 | 0.38±0.09 | 15.32±4.14 | 6.66±0.62 | 0.34±0.02 |
| LW | 23.4 | 32.2 | 0.39±0.08 | 18.74±1.92 | ||
| BR 2.1 | ||||||
| EW | 16.4 | 31.3 | 0.35±0.04 | 15.29±1.75 | 6.61±0.29 | 0.32±0.02 |
| LW | 13.4 | 29.7 | 0.39±0.04 | 18.39±2.38 | ||
| BR 2.2 | ||||||
| EW | 9.3 | 32.0 | 0.34±0.03 | 15.67±1.80 | 7.01±0.46 | 0.31±0.02 |
| LW | 17.7 | 29.4 | 0.37±0.02 | 19.08±1.71 | ||
| BR 2.3 | ||||||
| EW | 11.0 | 31.7 | 0.36±0.04 | 16.70±2.35 | 6.89±0.49 | 0.30±0.03 |
| LW | 17.3 | 27.8 | 0.33±0.03 | 17.82±1.24 | ||
| BR 4.1 | ||||||
| EW | 14.3 | 29.4 | 0.39±0.05 | 15.55±2.46 | 7.38±0.21 | 0.37±0.02 |
| LW | 7.7 | 30.3 | 0.38±0.05 | 17.12±2.81 | ||
| BR 4.2 | ||||||
| EW | 21.0 | 30.5 | 0.39±0.04 | 14.89±2.65 | 7.47±0.68 | 0.36±0.03 |
| LW | 9.2 | 30.8 | 0.37±0.03 | 16.51±1.49 | ||
| BR 4.3 | ||||||
| EW | 14.3 | 31.6 | 0.39±0.04 | 16.68±1.98 | 7.10±0.66 | 0.34±0.02 |
| LW | 9.6 | 30.1 | 0.37±0.05 | 15.88±2.86 | ||
| BR 4.4 | ||||||
| EW | 19.3 | 27.8 | 0.36±0.05 | 14.50±2.22 | 7.02±0.20 | 0.36±0.02 |
| LW | 11.1 | 28.0 | 0.43±0.04 | 18.53±1.72 | ||
| BR 6.1 | ||||||
| EW | 19.6 | 15.9 | 0.39±0.04 | 15.75±1.59 | 6.90±0.34 | 0.36±0.03 |
| LW | 7.5 | 29.9 | 0.43±0.05 | 18.34±2.51 | ||
| BR 6.2 | ||||||
| EW | 15.7 | 27.8 | 0.43±0.03 | 16.92±2.41 | 7.24±0.28 | 0.38±0.01 |
| LW | 7.0 | 31.5 | 0.43±0.02 | 18.13±1.59 | ||
| BR 6.3 | ||||||
| EW | 9.9 | 30.3 | 0.38±0.04 | 12.24±2.08 | 7.33±0.46 | 0.39±0.03 |
| LW | 8.5 | 28.7 | 0.41±0.03 | 20.17±1.14 | ||
| BR 6.4 | ||||||
| EW | 15.0 | 28.3 | 0.44±0.05 | 16.71±2.19 | 7.75±0.76 | 0.39±0.02 |
| LW | 13.6 | 29.0 | 0.43±0.03 | 18.81±1.31 | ||
| WR 2.1 | ||||||
| EW | 9.6 | 30.1 | 0.39±0.03 | 18.36±2.39 | 7.25±0.77 | 0.33±0.02 |
| LW | 8.3 | 29.3 | 0.36±0.03 | 18.07±1.37 | ||
| WR 2.2 | ||||||
| EW | 19.9 | 32.7 | 0.36±0.05 | 15.09±2.22 | 6.64±0.36 | 0.32±0.03 |
| LW | 8.7 | 29.1 | 0.35±0.03 | 17.68±1.71 | ||
| WR 2.3 | ||||||
| EW | 15.7 | 31.5 | 0.41±0.03 | 17.87±2.37 | 7.31±0.48 | 0.34±0.01 |
| LW | 8.4 | 29.3 | 0.43±0.02 | 20.43±0.82 | ||
| WR 2.4 | ||||||
| EW | 16.6 | 31.2 | 0.39±0.06 | 17.37±1.55 | 6.65±0.44 | 0.32±0.02 |
| LW | 8.1 | 29.5 | 0.39±0.04 | 18.61±1.61 | ||
| WR 6.1 | ||||||
| EW | 24.9 | 31.7 | 0.41±0.04 | 16.64±2.96 | 6.71±0.63 | 0.32±0.02 |
| LW | 10.7 | 30.6 | 0.41±0.03 | 18.57±1.68 | ||
| WR 6.2 | ||||||
| EW | 22.5 | 28.7 | 0.44±0.02 | 20.75±1.09 | 7.06±0.34 | 0.33±0.02 |
| LW | 9.7 | 30.6 | 0.38±0.02 | 19.51±0.98 | ||
| WR 6.3 | ||||||
| EW | 14.7 | 34.8 | 0.41±0.02 | 18.13±1.48 | 7.18±1.05 | 0.32±0.02 |
| LW | 9.9 | 34.2 | 0.36±0.03 | 18.35±1.09 | ||
| WR 6.4 | ||||||
| EW | 18.7 | 32.8 | 0.40±0.02 | 18.03±1.81 | 6.75±0.47 | 0.31±0.02 |
| LW | 19.0 | 33.6 | 0.35±0.03 | 17.29±1.93 | ||
| WR 6.5 | ||||||
| EW | 10.5 | 31.4 | 0.42±0.02 | 19.05±1.11 | 6.93±0.42 | 0.32±0.02 |
| LW | 9.7 | 31.3 | 0.39±0.04 | 19.17±1.69 | ||
| WR 12.1 | ||||||
| EW | 18.2 | 30.0 | 0.43±0.03 | 18.6±1.24 | 7.42±0.82 | 0.36±0.03 |
| LW | 10.4 | 29.6 | 0.40±0.02 | 20.72±1.15 | ||
| WR 12.2 | ||||||
| EW | 23.9 | 34.4 | 0.42±0.02 | 18.03±1.53 | 7.22±0.76 | 0.35±0.04 |
| LW | 14.1 | 32.3 | 0.41±0.04 | 18.99±1.93 | ||
| WR 12.3 | ||||||
| EW | 11.3 | 31.0 | 0.38±0.03 | 15.20±3.61 | 7.03±0.31 | 0.34±0.02 |
| LW | 11.9 | 33.3 | 0.39±0.02 | 17.73±2.15 | ||
| WR 12.4 | ||||||
| EW | 15.5 | 30.2 | 0.46±0.02 | 19.69±1.12 | 7.27±0.48 | 0.35±0.01 |
| LW | 7.5 | 32.9 | 0.42±0.03 | 20.79±2.78 | ||
| WR 12.5 | ||||||
| EW | 10.6 | 31.3 | 0.41±0.04 | 17.33±2.78 | 7.94±0.53 | 0.37±0.03 |
| LW | 15.8 | 30.8 | 0.42±0.03 | 20.75±2.57 | ||
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- Light scattering characterization of lignosulfonate structure in saline solutions
- Differences in wood properties of Picea abies L. Karst. in relation to site of provenance and population genetics
- Rapid determination of biomass and polypropylene in three types of wood plastic composites (WPCs) using FTIR spectroscopy and partial least squares regression (PLSR)
- Thermal modification of Southern pine combined with wax emulsion preimpregnation: effect on hydrophobicity and dimensional stability
- Mixed-mode fracture toughness of bond lines of PRF and PUR adhesives in European beech wood
- Effect of specimen dimension and pre-heating temperature on supercritical CO2 dewatering of radiata pine sapwood
- Sound absorption of wood-based materials
- Threshold for ion movements in wood cell walls below fiber saturation observed by X-ray fluorescence microscopy (XFM)
- Oxygen plasma treatment of bamboo fibers (BF) and its effects on the static and dynamic mechanical properties of BF-unsaturated polyester composites
- A combined view on composition, molecular structure, and micromechanics of fungal degraded softwood
- Morphological changes induced in wood samples by aqueous NaOH treatment and their effects on the conversion of cellulose I to cellulose II
- Young’s modulus and shear modulus of solid wood measured by the flexural vibration test of specimens with large height/length ratios
- Effects of cell wall ultrastructure on the transverse shrinkage anisotropy of Scots pine wood
- Short Note
- Reacted copper(II) concentrations in earlywood and latewood of micronized copper-treated Canadian softwood species
Articles in the same Issue
- Frontmatter
- Review Articles
- A large-scale test set-up for measuring VOC emissions from wood products under laboratory conditions in simulated real rooms
- Industrial waste water for biotechnological reduction of aldehyde emissions from wood products
- Original Articles
- Light scattering characterization of lignosulfonate structure in saline solutions
- Differences in wood properties of Picea abies L. Karst. in relation to site of provenance and population genetics
- Rapid determination of biomass and polypropylene in three types of wood plastic composites (WPCs) using FTIR spectroscopy and partial least squares regression (PLSR)
- Thermal modification of Southern pine combined with wax emulsion preimpregnation: effect on hydrophobicity and dimensional stability
- Mixed-mode fracture toughness of bond lines of PRF and PUR adhesives in European beech wood
- Effect of specimen dimension and pre-heating temperature on supercritical CO2 dewatering of radiata pine sapwood
- Sound absorption of wood-based materials
- Threshold for ion movements in wood cell walls below fiber saturation observed by X-ray fluorescence microscopy (XFM)
- Oxygen plasma treatment of bamboo fibers (BF) and its effects on the static and dynamic mechanical properties of BF-unsaturated polyester composites
- A combined view on composition, molecular structure, and micromechanics of fungal degraded softwood
- Morphological changes induced in wood samples by aqueous NaOH treatment and their effects on the conversion of cellulose I to cellulose II
- Young’s modulus and shear modulus of solid wood measured by the flexural vibration test of specimens with large height/length ratios
- Effects of cell wall ultrastructure on the transverse shrinkage anisotropy of Scots pine wood
- Short Note
- Reacted copper(II) concentrations in earlywood and latewood of micronized copper-treated Canadian softwood species
