Prediction model based on chemical composition change for the mechanical degradation of Korean pine (Pinus koraiensis) after brown-rot fungi (Gloeophyllum trabeum) invasion

Abstract In order to predict the mechanical properties of Korean pine after brown-rot decay based on its chemical composition change, 252 samples were prepared and exposed to a 14-week accelerated laboratory decay test using the brown-rot fungus Gloeophyllum trabeum. The mass loss, parallel-to-grain compressive strength, parallel-to-grain tensile strength and bending strengths were tested. Then chemical components and scanning electron micrograph analysis were conducted every two weeks. Results indicated that the mass loss rates of the samples increased with the increasing decay time and were negatively correlated with the sample volume. The strength loss rates were positively correlated with the decay time and mass loss rates. After 14 weeks the average strength loss rates of the parallel-to-grain compressive, tensile and bending samples reached 32%, 41% and 41%, respectively. Strengths degradation was found sensitive to the change of cellulose and hemicellulose contents. Further, mathematical regression models were proposed based on the content changes of the cellulose and hemicellulose to quantitatively predict the degradation of the strengths of Korean pine after brown-rot decay.

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Changes in Carbon Sequestration in Wood During Decay by Brown- and White-Rot Fungi

Journal of Biobased Materials and Bioenergy ◽

10.1166/jbmb.2020.1968 ◽

2020 ◽

Vol 14 (3) ◽

pp. 414-419

Author(s):

Huadong Xu ◽

Jiedong Wei ◽

Yanan Di ◽

Ruixia Qin ◽

Zonglin Zhen

Keyword(s):

Carbon Sequestration ◽

Mass Loss ◽

Decay Time ◽

Carbon Emission ◽

Wood Decay ◽

Brown Rot ◽

White Rot ◽

Korean Pine ◽

Decay Test ◽

The Absolute

Wood decay is a releasing process of carbon fixed in the wood. The study on carbon sequestration change caused by decay can provide a theoretical basis for wood preservation and utilization. At present, there are few reports on decay influence on wood carbon emission and no corresponding quantitative data. Therefore, one broad-leaved species, Poplar, and one coniferous species, Korean pine, were selected as the research object, and brown rot fungus (Gloeephyllum trabeum) and white rot fungus (Coriolus versicolor) were used to conduct accelerated decay test on wood samples in the laboratory. During decay, specimens were taken out in different periods to measure chemical properties, mass loss and carbon sequestration. The influence of decay time on carbon sequestration, chemical component and mass loss were then analyzed and the change rule of carbon sequestration were finally studied. The results showed that with increasing decay time, the relative carbon sequestration content of wood affected by different types rot fungi decreased, which was consistent with the change rule of mass loss, indicating that decay would lead to a loss of wood mass and affect its carbon sequestration. However, the absolute carbon sequestration (measured value of carbon sequestration) after brown rot treatment did not decrease but increased slightly, which was different from previous expectation. According to the analysis, with increasing brown rot time, the absolute content and proportion of lignin in wood samples increased slightly, while the corresponding value of holocellulose (including α-cellulose and hemicellulose) decreased significantly. The carbon content of lignin per unit mass is higher than that of holocellulose (Poplar 64.08% > 37.38%; Korean pine 66.37% > 35.94%), resulting in absolute carbon sequestration in wood increases instead of decreases. In conclusion, the change of lignin proportion during the process of brown rot is the decisive factor affecting the change of absolute carbon sequestration. This study focused on two aspects of wood decay and wood carbon sequestration, systematically analyzed the change rule and internal mechanism of wood carbon sequestration with the increase of wood decay degree, and accumulated basic data for wood carbon emission reduction and wood prevention.

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Outdoor Wood Mats-Based Engineering Composite: Influence of Process Parameters on Decay Resistance against Wood-Degrading Fungi Trametes versicolor and Gloeophyllum trabeum

Polymers ◽

10.3390/polym13183173 ◽

2021 ◽

Vol 13 (18) ◽

pp. 3173

Author(s):

Minzhen Bao ◽

Neng Li ◽

Yongjie Bao ◽

Jingpeng Li ◽

Hao Zhong ◽

...

Keyword(s):

Chemical Composition ◽

Mass Loss ◽

Process Parameters ◽

Trametes Versicolor ◽

Decay Resistance ◽

Resin Content ◽

White Rot ◽

White Rot Fungus ◽

Gloeophyllum Trabeum ◽

Influence Of Process Parameters

The process parameters significantly influence the preparation and final properties of outdoor wood mats-based engineering composite (OWMEC). During outdoor use, wood composites are susceptible to destruction by rot fungi. Herein, the role of process parameters such as density and resin content on OWMEC resistance to fungal decay was investigated. The poplar OWMEC samples were exposed to white-rot fungus Trametes versicolor and brown-rot fungus Gloeophyllum trabeum for a period of 12 weeks. The chemical composition, crystallinity, and morphology were evaluated to investigate the effect of process parameters on the chemical composition and microstructure of the decayed OWMEC. With an increase in the density and resin content, the mass loss of the decayed OWMEC decreased. The highest antifungal effect against T. versicolor (12.34% mass loss) and G. trabeum (19.43% mass loss) were observed at a density of 1.15 g/m3 and resin content of 13%. As results of the chemical composition and microstructure measurements, the resistance of OWMEC against T. versicolor and G. trabeum fungi was improved remarkably by increasing the density and resin content. The results of this study will provide a technical basis to improve the decay resistance of OWMEC in outdoor environments.

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De Novo Synthesis of 4,5-Dimethoxycatechol and 2,5-Dimethoxyhydroquinone by the Brown Rot FungusGloeophyllum trabeum

Applied and Environmental Microbiology ◽

10.1128/aem.65.2.674-679.1999 ◽

1999 ◽

Vol 65 (2) ◽

pp. 674-679 ◽

Cited By ~ 98

Author(s):

Andrzej Paszczynski ◽

Ronald Crawford ◽

David Funk ◽

Barry Goodell

Keyword(s):

Mass Spectrometry ◽

Methylene Chloride ◽

De Novo ◽

Brown Rot ◽

Gas Chromatography Mass Spectrometry ◽

Gloeophyllum Trabeum ◽

De Novo Synthesis ◽

Brown Rot Fungus ◽

Synthetic Standard ◽

Brown Rot Decay

ABSTRACT The new dimethoxycatechol 4,5-dimethoxy-1,2-benzenediol (DMC) and the new dimethoxyhydroquinone 2,5-dimethoxy-1,4-benzenediol (DMH) were isolated from stationary cultures of the brown rot fungusGloeophyllum trabeum growing on a glucose mineral medium protected from light. The structure was elucidated by gas chromatography-mass spectrometry through comparison to a synthetic standard. Further confirmation was obtained by forming a dimethoxyoxazole derivative by condensation of DMC with methylene chloride and through examination of methylated derivatives. DMC and DMH may serve as ferric chelators, oxygen-reducing agents, and redox-cycling molecules, which would include functioning as electron transport carriers to Fenton’s reactions. Thus, they appear to be important components of the brown rot decay system of the fungus.

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Effects of Wood Moisture Content and the Level of Acetylation on Brown Rot Decay

Forests ◽

10.3390/f11030299 ◽

2020 ◽

Vol 11 (3) ◽

pp. 299 ◽

Cited By ~ 4

Author(s):

Samuel L. Zelinka ◽

Grant T. Kirker ◽

Amy B. Bishell ◽

Samuel V. Glass

Keyword(s):

Moisture Content ◽

Mass Loss ◽

Linear Trend ◽

Fungal Growth ◽

Weight Percent Gain ◽

Brown Rot ◽

Weight Percent ◽

Wood Moisture Content ◽

Wood Moisture ◽

Brown Rot Decay

Acetylation is one of the most common types of wood modification and is commercially available throughout the world. Many studies have shown that acetylated wood is decay resistant at high levels of acetylation. Despite its widespread use, the mechanism by which acetylation prevents decay is still not fully understood. It is well known that at a given water activity, acetylation reduces the equilibrium moisture content of the wood cell wall. Furthermore, linear relationships have been found between the acetylation weight percent gain (WPG), wood moisture content, and the amount of mass loss in decay tests. This paper examines the relationships between wood moisture content and fungal growth in wood, with various levels of acetylation, by modifying the soil moisture content of standard soil block tests. The goal of the research is to determine if the reduction in fungal decay of acetylated wood is solely due to the reduction in moisture content or if there are additional antifungal effects of this chemical treatment. While a linear trend was observed between moisture content and mass loss caused by decay, it was not possible to separate out the effect of acetylation from fungal moisture generation. The data show significant deviations from previously proposed models for fungal moisture generation and suggest that these models cannot account for active moisture transport by the fungus. The study helps to advance our understanding of the role of moisture in the brown rot decay of modified wood.

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Mass Loss Rates and Nutrient Dynamics of Decomposing Fine Roots in a Sawtooth Oak and a Korean Pine Stands

The Korean Journal of Ecology ◽

10.5141/jefb.2002.25.4.235 ◽

2002 ◽

Vol 25 (4) ◽

pp. 235-239 ◽

Cited By ~ 4

Author(s):

Choonsig Kim

Keyword(s):

Mass Loss ◽

Fine Roots ◽

Nutrient Dynamics ◽

Korean Pine ◽

Pine Stands ◽

Sawtooth Oak ◽

Loss Rates

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Mode of action of brown rot decay resistance of thermally modified wood: resistance to Fenton’s reagent

Holzforschung ◽

10.1515/hf-2015-0141 ◽

2016 ◽

Vol 70 (7) ◽

pp. 691-697 ◽

Cited By ~ 13

Author(s):

Reza Hosseinpourpia ◽

Carsten Mai

Keyword(s):

Cell Wall ◽

Brown Rot ◽

Strength Loss ◽

Decay Resistance ◽

Fenton’S Reagent ◽

Fenton's Reagent ◽

Brown Rot Fungi ◽

Brown Rot Decay ◽

Wood Resistance ◽

Fe Ions

Abstract The resistance of heat treated (HT) wood to brown rot fungi has been investigated, while the role of the Fenton reaction (FR) in the initial phase of degradation was in focus. Micro-veneers made of Scots pine, were HT with various intensities and their mass losses (MLHT) were determined before soaking with a solution of Fenton’s reagent containing Fe ions and hydrogen peroxide. The mass loss of the veneers treated that way (MLFT), their tensile strength loss (TSLFT) and the H2O2 decomposition were observed. The MLFT, TSLFT, and H2O2 loss decreased with increasing MLHT of the veneers. Soaking of the veneers in acetate buffer containing only Fe without H2O2 revealed that the heat treatment (HT) strongly reduces the Fe uptake by the cell walls. FTIR spectroscopy indicated oxidation of the unmodified control veneers but did not reveal predominant decay of cell wall components; the HT veneers were not changed at all due to FR. It was concluded that the reason for the enhanced resistance of HT wood to FR is attributable to hindered diffusion of Fe ions into the wood cell wall.

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Spectroscopic Analyses of Hot Extreme Helium Stars

International Astronomical Union Colloquium ◽

10.1017/s025292110009059x ◽

1985 ◽

Vol 87 ◽

pp. 32-50

Author(s):

U. Heber

Keyword(s):

Chemical Composition ◽

Mass Loss ◽

Spectroscopic Analyses ◽

Helium Stars ◽

Order Of Magnitude ◽

History Of ◽

Nuclear History ◽

Halo Population ◽

Loss Rates

AbstractSpectroscopic fine analyses of hot extreme helium stars are reviewed. The chemical composition is discussed in detail and conclusions as to the nuclear history of the atmospheric material are drawn. Evidence of inhomogeneities among the hot extreme helium stars is presented and it is concluded that the extreme helium stars can be found in the halo population (BD+10°2179) as well as in the disc population. Their mass loss rates are of the same order of magnitude (10−9 M⊙/yr) as those of normal stars. Four helium rich sdO stars are identified as possible descendants of the B-type extreme helium stars.

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The Theory of Radiation Driven Stellar Winds and the Wolf-Rayet Phenomenon

Symposium - International Astronomical Union ◽

10.1017/s0074180900028850 ◽

1982 ◽

Vol 99 ◽

pp. 185-196

Author(s):

David C. Abbott

Keyword(s):

Chemical Composition ◽

Mass Loss ◽

Radiation Pressure ◽

Stellar Winds ◽

List Type ◽

Ob Stars ◽

Wind Theory ◽

Loss Rates

Peter Conti has a tradition of always talking about 0-type stars at Wolf-Rayet symposia, and Wolf-Rayet stars at 0 star symposia. Since there is no well-developed theory for the origin of the winds of WR stars, it is my pleasure to join Peter's tradition, and to talk mainly about the theory of radiation driven winds in OB stars. The advantage of OB stars is that there exists a fairly complete wind theory, which agrees well with the available observations. The question is, can the mass loss observed from Wolf-Rayet stars be explained by a version of this wind theory which is scaled to the conditions found in the envelopes of Wolf-Rayet stars? The topics I consider are: —The calculated radiation pressure in OB stars, and its dependence on temperature, density, and chemical composition.—A comparison between predicted and observed mass loss rates and terminal velocities for OB stars.—The applicability of the standard radiation driven wind models to Wolf-Rayet stars.—Speculations on how Wolf-Rayet stars achieve their enormous mass loss rates within the context of the radiation pressure mechanism.

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Experimental evidence that fungal symbionts of beetles suppress wood decay by competing with decay fungi

10.7287/peerj.preprints.27676 ◽

2019 ◽

Author(s):

James Skelton ◽

Andrew Loyd ◽

Jason A. Smith ◽

Robert A. Blanchette ◽

Benjamin W. Held ◽

...

Keyword(s):

Mass Loss ◽

Wood Decay ◽

Brown Rot ◽

Inhibitory Effects ◽

Ambrosia Beetles ◽

Decay Fungi ◽

Bark And Ambrosia Beetles ◽

Symbiotic Fungi ◽

Brown Rot Decay ◽

Forest Biology

Throughout forests worldwide, bark and ambrosia beetles inoculate dead and dying trees with symbiotic fungi. We experimentally determined the effects of three common and widely distributed ascomycete symbionts, and one introduced Asian basidiomycete symbiont on the decay of pine sapwood. Ascomycetes caused less than 5% mass loss and no structural degradation, whereas the basidiomycete Flavodon ambrosius caused nearly 15% mass loss and visible degradation of wood structure. In co-inoculation experiments, the beetle symbionts Ophiostoma ips and Raffaelea fusca reduced white and brown rot decay through competition with Ganoderma curtisii and Phaeolus schweinitzii, respectively. The inhibitory effects of O. ips and R. fusca on decay were negated when co-inoculated with F. ambrosius, suggesting that widespread introduction of this beetle symbiont could alter forest carbon fluxes. In contrast to the predominant forest biology narrative, most bark and ambrosia beetles introduce fungi that delay rather than facilitate tree biomass recycling.

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