The fungal resistance of wood modified with glutaraldehyde

Abstract Scots pine sapwood (Pinus sylvestris L.) and European beech wood (Fagus sylvatica L.) were treated with glutaraldehyde (GA) in aqueous solution in the presence of magnesium chloride as a catalyst to evaluate the durability improvement towards staining and rot fungi. The GA modified specimens were dipped in a spore suspension of the blue stain fungus Aureobasidium pullulans and incubated for 8 weeks. The growth on both pine and beech wood was restrained, when the weight percent gain (WPG) of the specimens was above 7%. Under this condition, GA-modified beech wood did not suffer any mass loss after incubation with the white rot fungus Trametes versicolor. The threshold to prevent decay of beech and pine specimens towards the brown rot fungus Coniophora puteana was at a WPG of only 3%. GA treatment to a WPG over 6% protected the Scots pine stakes from soft rot decay during 32 weeks’ exposure according to ENv 807 (2001).

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The Impact of Paraffin-Thermal Modification of Beech Wood on Its Biological, Physical and Mechanical Properties

Forests ◽

10.3390/f10121102 ◽

2019 ◽

Vol 10 (12) ◽

pp. 1102 ◽

Cited By ~ 3

Author(s):

Ladislav Reinprecht ◽

Miroslav Repák

Keyword(s):

Mechanical Properties ◽

Bending Strength ◽

Beech Wood ◽

Physical And Mechanical Properties ◽

Brown Rot ◽

European Beech ◽

White Rot ◽

White Rot Fungus ◽

Poria Placenta ◽

The Impact

The European beech (Fagus sylvatica L.) wood was thermally modified in the presence of paraffin at the temperatures of 190 or 210 °C for 1, 2, 3 or 4 h. A significant increase in its resistance to the brown-rot fungus Poria placenta (by 71.4%–98.4%) and the white-rot fungus Trametes versicolor (by 50.1%–99.5%) was observed as a result of all modification modes. However, an increase in the resistance of beech wood surfaces to the mold Aspergillus niger was achieved only under more severe modification regimes taking 4 h at 190 or 210 °C. Water resistance of paraffin-thermally modified beech wood improved—soaking reduced by 30.2%–35.8% and volume swelling by 26.8%–62.9% after 336 h of exposure in water. On the contrary, its mechanical properties worsened—impact bending strength decreased by 17.8%–48.3% and Brinell hardness by 2.4%–63.9%.

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Changes in sorption and electrical properties of wood caused by fungal decay

Holzforschung ◽

10.1515/hf-2018-0171 ◽

2019 ◽

Vol 73 (5) ◽

pp. 445-455 ◽

Cited By ~ 4

Author(s):

Christian Brischke ◽

Simon Stricker ◽

Linda Meyer-Veltrup ◽

Lukas Emmerich

Keyword(s):

Beech Wood ◽

Sorption Isotherms ◽

Brown Rot ◽

European Beech ◽

White Rot ◽

White Rot Fungus ◽

Decayed Wood ◽

Vapor Sorption ◽

Fungal Decay ◽

Dynamic Vapor Sorption

Abstract As wet wood is prone to degradation by wood-destroying fungi, the monitoring of the moisture content (MC) of wood can be used to quantify the risk of fungal infestation. Fungal decay alters the sorption and electrical conductivity of wood, and thus the goal of the present study was to measure the electrical resistance (R) of wood after fungal decay as a function of MC. Scots pine sapwood (Pinus sylvestris L.) and European beech wood (Fagus sylvatica L.) were submitted to decay by Coniophora puteana (a brown rot fungus, BR) and Trametes versicolor (a white rot fungus, WR) and the mass loss (ML) due to the fungal metabolism was measured. The sorption isotherms were determined by dynamic vapor sorption (DVS), and comparative gravimetric- and R-based MC measurements were conducted. BR and WR reduced the sorption of wood and lowered its R in the hygroscopic range, where the decay led to an overestimation of wood MC, while wood MC was dramatically underestimated above fiber saturation (FS). Specimens showed an MC well above FS if measured directly after harvesting and an increased R compared to undecayed wood at a given MC. BR-decayed specimens were dried and rewetted, and such specimens showed an elevated R beyond FS. In the case of WR-decayed wood, the R was reduced at a given MC.

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Ability of some species of fungi of the Basidiomycetes class to degrade cellulose and lignocellulose substrates

Acta Mycologica ◽

10.5586/am.1983.025 ◽

2014 ◽

Vol 19 (2) ◽

pp. 323-330

Author(s):

Zdzisław Tagoński

Keyword(s):

Beech Wood ◽

Brown Rot ◽

White Rot ◽

White Rot Fungus ◽

Cellulolytic Enzymes ◽

Pine Wood ◽

Wood Meal ◽

Fomes Fomentarius

Studies were carried-out on the ability of 18 strains of 15 white-rot and brown-rot basidiomycetons fungi to degrade wood components and to synthesize cellulolytic enzymes and laccase. 28,5% lignin and 26,1% carbohydrates of pine wood meal, 46,2% lignin and 67,8% carbohydrates of beech wood meal was degraded after 6 weeks incubation by the white-rot fungus Phanerochate chrysosporium. The highest activity of laccase was obtained in from fungi Coriotus zonatus and Fomes fomentarius.

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Effect of short-chain silicones bearing different functional groups on the resistance of pine (Pinus sylvestris L.) and beech (Fagus sylvatica L.) against decay fungi

Holzforschung ◽

10.1515/hf-2012-0065 ◽

2013 ◽

Vol 67 (4) ◽

pp. 447-454 ◽

Cited By ~ 7

Author(s):

Malte Pries ◽

Roland Wagner ◽

Karl-Heinz Kaesler ◽

Holger Militz ◽

Carsten Mai

Keyword(s):

Mass Loss ◽

Functional Groups ◽

Beech Wood ◽

Treated Wood ◽

Weight Percent Gain ◽

Weight Percent ◽

Fungal Resistance ◽

Short Chain ◽

Cross Sectional ◽

Decay Fungi

Abstract Blocks of pine sapwood and beech wood were treated with water-based emulsions containing short-chain silicones with different α-ω-bonded functional groups, such as diamino, carboxyl and carbonyl, betain, and epoxy groups. The weight percent gain upon treatment of the pine wood specimens was relatively high (10%–20%), but their cross-sectional bulking was low (1%–2.5%). Thus, the anti-shrink efficiency (ASE) due to the treatment was also low. The first water-submersion tests revealed some hydrophobation of the treated wood. A second submersion test, however, revealed successful hydrophobation only for betain-functionalised material. The carboxylated silicone even increased the speed of water uptake as compared to the controls. The samples treated with silicones bearing epoxy, diamino, and carboxy functionalities showed a distinct reduction in mass loss compared to the control samples after 16 weeks of incubation with the fungi Coniophora puteana and Trametes versicolor according to EN 113 and CEN/TS 15083-1, whereas the betain-functionalised silicone did not enhance fungal resistance. All silicones tested lowered the mass loss in a soft rot test according to ENv 807. The mode of action of the silicones is discussed.

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Influence of Copper and Biopolymer/Saqez Resin on the Properties of Poplar Wood

Forests ◽

10.3390/f11060667 ◽

2020 ◽

Vol 11 (6) ◽

pp. 667 ◽

Cited By ~ 1

Author(s):

Huijun Dong ◽

Mohsen Bahmani ◽

Sohrab Rahimi ◽

Miha Humar

Keyword(s):

Physical Properties ◽

Trametes Versicolor ◽

Weight Percent Gain ◽

Weight Percent ◽

Decay Resistance ◽

White Rot ◽

White Rot Fungus ◽

Poplar Wood ◽

Wood Protection ◽

Increasing Trend

There is an increasing trend in the use of environmentally-friendly materials in wood protection. This includes the use of less toxic active ingredients, as well as better fixation. This study investigates the formulation based on the combination of copper and Saqez resin on the physical and biological resistance properties of poplar wood. Samples were treated by either copper-ethanolamine (Cu/MEA) and/or Saqez resin at various treatment levels. A vacuum pressure procedure was applied. The retention, weight percent gain, water absorption, volumetric swelling, and decay resistance of the samples were then determined. The highest retention and weight percent gain were obtained in the samples treated with the combination of copper-based system and Saqez resin. Additionally, the combination of the copper and Saqez improved the physical properties and decay-resistance against white-rot fungus Trametes versicolor.

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Effects of white rot and brown rot decay on the drilling resistance measurements in wood

Holzforschung ◽

10.1515/hf-2017-0204 ◽

2018 ◽

Vol 72 (10) ◽

pp. 905-913 ◽

Cited By ~ 3

Author(s):

Evgenii Sharapov ◽

Christian Brischke ◽

Holger Militz ◽

Elena Smirnova

Keyword(s):

Scots Pine ◽

Free Water ◽

Brown Rot ◽

European Beech ◽

White Rot ◽

Drilling Tool ◽

Significant Difference ◽

Brown Rot Decay ◽

Drilling Resistance ◽

The Impact

AbstractAn IML-RESI PD 400 drilling tool and a standard spade drill bit (IML System GmbH, Wiesloch, Germany) were used to study the impact of white and brown rot decay on drilling resistance (DR) measurements in wood. In total, 720 drillings were made in specimens of Scots pine (Pinus sylvestrisL.) heartwood and sapwood, European beech (Fagus sylvaticaL.) and English oak (Quercus roburL.), which were decayed byConiophora puteanaandTrametes versicolor. Drillings were made with specimens conditioned in normal climate (20°C/65% RH) and with specimens vacuum-impregnated in water. DR and feeding force (FF) were negatively correlated with mass loss (ML) due to fungal decay. The intensity of reduction was higher for DR than for FF with increasing ML for all decay types and moisture contents (MCs). A significant difference (at 95% confidence level) in DR was found between decay types using water-saturated (WS) Scots pine specimens (3–35% ML). In most cases, DR revealed a higher predictive power of the models for ML prediction than FF. Free water in decayed specimens significantly reduced the DR and FF. Hence, the effect of ML on DR and FF of decayed and WS wood was less prominent.

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Fungal degradation of bamboo samples

Holzforschung ◽

10.1515/hf.2011.084 ◽

2011 ◽

Vol 65 (6) ◽

pp. 883-888 ◽

Cited By ~ 14

Author(s):

Olaf Schmidt ◽

Dong Sheng Wei ◽

Walter Liese ◽

Elisabeth Wollenberg

Keyword(s):

Schizophyllum Commune ◽

Brown Rot ◽

Soft Rot ◽

Test Methods ◽

White Rot ◽

White Rot Fungus ◽

Bamboo Species ◽

Brown Rot Fungus ◽

Rate Of Decay ◽

Severe Deterioration

Abstract The degradation of several Asian bamboo species by white-, brown-, and soft-rot fungi was investigated under laboratory conditions by means of different test methods. Severe deterioration was caused by all three fungi types. The bamboo species differed in durability. Samples from 6 months young culms decayed more than older ones. There were no significant differences between 1- and 3-year-old culms. Samples taken from the culm top were more vulnerable to decay than those from the bottom. Wet bamboo samples with soil contact were especially degraded by the white-rot fungus Schizophyllum commune, whereas the brown-rot fungus Coniophora puteana produced the greatest mass loss in drier samples. The sealing of bamboo crosscut ends reduced the rate of decay.

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The Resistance of Wood Chemically Modified with Isocyanates. Part 1. Brown Rot, White Rot and Acid Chlorite Delignification

Holzforschung ◽

10.1515/hf.1999.039 ◽

1999 ◽

Vol 53 (3) ◽

pp. 230-236 ◽

Cited By ~ 9

Author(s):

F. Cardias Williams ◽

M.D. Hale

Keyword(s):

Chemical Modification ◽

Weight Percent Gain ◽

Brown Rot ◽

Weight Percent ◽

Pinus Nigra ◽

Fungal Species ◽

White Rot ◽

Sodium Chlorite ◽

Pycnoporus Sanguineus ◽

Wood Protection

Summary This study was to assess the bioprotectant performance of chemical modification with three different isocyanates (n-butyl, hexyl and 1,6-diisocyanatohexane, BuNCO, HeNCO and HDI respectively) in Corsican pine (Pinus nigra Schneid) sapwood. Wood-isocyanate bond formation was verified by the increase in sample weight, volume and by infra-red spectroscopy. Basidiomycete (Coniophora puteana, Gloeophyllum trabeum, Coriolus versicolor, Pycnoporus sanguineus) decay tests demonstrated protection by chemical modification. The relationships of fungal species, weight percent gain (WPG), and decay induced weight loss were examined. One of the brown rot fungi, C. puteana, showed higher threshold protection values than the other fungi tested and the diisocyanate showed better performance. Chemical characteristics of the sound and brown rotted wood (C. puteana) have been examined using sulphuric acid and sodium chlorite procedures to clarify the principles which govern isocyanate modifications and restrict fungal decay. These demonstrated that appreciable wood protection against C. puteana only occurred when the holocellulose fraction showed substantial changes due to chemical modification.

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Influence of Copper and Biopolymer/Saqez Resin on the Properties of Poplar Wood

10.20944/preprints202005.0131.v1 ◽

2020 ◽

Author(s):

Huijun Dong ◽

Mohsen Bahmani ◽

Sohrab Rahimi ◽

Miha Humar

Keyword(s):

Physical Properties ◽

Trametes Versicolor ◽

Weight Percent Gain ◽

Weight Percent ◽

Decay Resistance ◽

White Rot ◽

White Rot Fungus ◽

Poplar Wood ◽

Wood Protection ◽

Protection Technology

There is an increasing interest in applying environmentally-friendly materials in wood protection technology. This include the use of less toxic active ingredients, as well as better fixation. This study investigates the formulation based on the combination of copper and Saqez resin on the physical and biological resistance properties of poplar wood. Samples were treated by either copper-ethanolamine (Cu/MEA) and/or Saqez resin at various treatment levels. A vacuum pressure procedure was applied. The retention, weight percent gain, water absorption, volumetric swelling, and decay resistance of the samples were then determined. The highest retention and weight percent gain were obtained at the samples treated with the combination of copper-based system and Saqez resin. Additionally, the combination of the copper and Saqez improved the physical properties and decay-resistance against white-rot fungus Trametes versicolor.

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Degradation of the lignocellulose complex in wood

Canadian Journal of Botany ◽

10.1139/b95-350 ◽

1995 ◽

Vol 73 (S1) ◽

pp. 999-1010 ◽

Cited By ~ 158

Author(s):

Robert A. Blanchette

Keyword(s):

Cell Wall ◽

White Rot Fungi ◽

Brown Rot ◽

Forest Products ◽

Soft Rot ◽

Cell Types ◽

White Rot ◽

Bacterial Degradation ◽

White Rot Fungus ◽

Type I

Degradation of the lignocellulose complex in wood varies depending on the microorganism causing decay. The degradative processes of white-, brown-, and soft-rot fungi as well as different forms of bacterial degradation are presented. Ultrastructural methods were used to elucidate cell-wall alterations that occurred during the various stages of decay. In wood inoculated with the white-rot fungus Ceriporiopsis subvermispora, changes in the cell wall, such as electron-dense zones after staining with uranyl acetate, were evident during incipient stages of decay. The ratio of syringyl:guaiacyl lignin of different woods, different cell types, and even the different layers within a cell wall influenced the type and extent of decay by white-rot fungi. Soft rots caused unique changes in the lignocellulose matrix. The type of wood substrate governed the form (type I or type II) of soft rot that occurred. Brown-rot fungi depolymerized cellulose early in the decay process and degraded cellulose without prior removal of lignin. Bacterial degradation was common in waterlogged woods and three forms, tunneling, erosion and cavitation, are discussed. In addition to an improved understanding of decay processes in living trees and forest products, knowledge of decomposition mechanisms is important to utilize effectively these microorganisms for new industrial bioprocessing technologies. Key words: biodegradation, white rot, brown rot, soft rot, bacterial degradation.

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