Your search resulted in 288 documents. Displaying 25 entries per page.
Postia placenta gene expression of oxidative and carbohydrate metabolism related genes during growth in furfurylated wood
2009 - IRG/WP 09-10701
A range of studies the last decade have shown that modified wood can provide excellent protection against a range of wood deteriorating organisms, including decay fungi. However, we still lack information about why the modified wood is protected from microbial attack. Several hypotheses have been put forward e.g. inhibition of action of specific enzymes, but they still need testing. An understandi...
G Alfredsen, C G Fossdal
Durability and fungal colonisation patterns in wood samples after six years in soil contact evaluated with qPCR, microscopy, TGA, chitin- and ergosterol assays
2009 - IRG/WP 09-20402
There is a need to establish new objective and sensitive methods for early detection and quantification of decay fungi in wood materials. Molecular methods have proven to be a useful tool within wood protection issues, however, this field is still poorly explored and so far relatively few have used these methods within the field of wood deterioration. Among the techniques used in the indirect quan...
A Pilgård, G Alfredsen, I Børja, C Björdal
Effect of Preservative Treatment on Fungal Colonization of Teak, Redwood, and Western Red Cedar
2009 - IRG/WP 09-20404
Fungal flora present in preservative treated samples or non-treated samples from sapwood and heartwood of teak, western red cedar, redwood, and southern yellow pine was assessed after 6 to 18 months of exposure near Hilo, Hawaii. The objectives were to compare fungal composition and diversity between treated and non-treated samples, and to examine the use of molecular techniques for assessing fung...
Y Cabrera, C Freitag, J J Morrell
Fungal decay resistance and durability of wood products made from borax-impregnated wood and bonded with corn starch and tannin adhesive
2009 - IRG/WP 09-30494
At present, the production of wood composites mainly relies on the petrochemical-based and formaldehyde-based adhesives such as phenol formaldehyde (PF) resins and urea formaldehyde (UF) resins, which are non-renewable and therefore ultimately limited in supply. This paper concerns the decay resistance of wood products bonded with a new, environment-friendly adhesive derived from abundant and rene...
A Moubarik, A Pizzi, A Allal, F Charrier, B Charrier
Potential synergy between natural product extracts for limiting fungal decay
2009 - IRG/WP 09-30495
Natural products often exhibit tremendous potential for inhibiting various microorganisms when they are tested in petri dish tests, but perform poorly when tested in vivo. The failures can often be attributed to a lack of broad spectrum activity against the range of organisms present in a natural environment. One method for overcoming this challenge is to use extracts from a number of sources with...
M Maoz, C Freitag, J J Morrell
Synthesis of a rosin amide and its resistance to wood decay fungi
2009 - IRG/WP 09-30517
Rosin was reacted with diethyltriamine (DETA) after being modified by acryl acid with the weight ratio of 4.5:1 and a rosin amide (RA) derivative was produced at the conditions as follows: modified rosin and DETA mole ratio of 1:3.5, dimethylbenzene as water carrying agent, reaction temperature of 160-180°C, and reaction time of 8h. The chemical structure of the product as RA was identified by F...
Shuangyue Li, Shujun Li, Jing Wang
Fungal Attack on Lignin and Cellulose: Elucidation of Brown- and White-Rot Mechanisms Comparing Biomimetic and In-Vivo Degradation Patterns
2010 - IRG/WP 10-10714
This paper examines research and hypotheses that have been developed over several years on wood degradation mechanisms. This information is combined with new data and analyses to explain why wood decay patterns caused by brown-rot fungi and specific types of white-rot fungi are different. New data, including work with both biomimetic studies on low molecular weight compounds, degradative enzymes, ...
V Arantes, B Goodell, A M F Milagres, Yuhui Qian, T Filley, J Jellison, S Kelley
Seasonal shifts of fungal community structure at the interface of treated or untreated wood and soil
2010 - IRG/WP 10-10721
Many wood species are degraded rapidly in soil by the fungal community. In order to preserve wood and structures in which it is used, chemical preservatives are used. Little is known about the interaction of treated wood and the surrounding soil fungal community. For this work, presented at IRG 41, wooden specimens (Pinus sylvestris sapwood, sizes 25 mm x 50 mm x 500 mm (longitudinal)) were treate...
M Noll, I Stephan
Frequency of fungal decay in softwood windows in Germany
2010 - IRG/WP 10-10725
Knowing how often fungal decay occurs is a fundamental basis for general recommendations of preservative measures. To optimize the German recommendations for chemical wood preservation of windows made out of pine or spruce more than 2000 windows have been inspected. All windows had an opaque coating and were between 2 and 17 years old. The selection of the inspected windows was kept as randomly as...
D Lukowsky, O Moarcas, A Luette
Chemical mediated depolymerization of cotton cellulose for the understanding of non-enzymatic fungal decay
2010 - IRG/WP 10-10731
Small, low molecular weight non-enzymatic compounds have been linked to the early stages of brown rot decay as the enzymes involved with holocellulose degradation are found to be too large to penetrate the S3 layer of intact wood cells. The most pronounced of these which were analyzed in this study are hydrogen peroxide, iron, and oxalic. The compounds related to the Fenton reaction: the combinati...
A C Steenkjær Hastrup, B Jensen, F Green III
Postia placenta gene expression during growth in furfurylated wood
2010 - IRG/WP 10-10734
Modified wood can provide protection against a range of wood deteriorating organisms. But we still lack information about why the modified wood is protected from microbial attack. Several hypotheses have been put forward for the mode of action against wood decaying fungi, including inhibition of action of specific enzymes, but they still need further testing. In this study gene expression of the b...
G Alfredsen, C G Fossdal
Natural durability of African Padauk and Niove. Comparison of new trials and former data from the CIRAD database
2010 - IRG/WP 10-10743
African Padauk (Pterocarpus soyauxii) and Niove (Staudia kamerunensis) were tested in laboratory against Basidiomycetes. The results were calculated according to the requirements of EN 350-1 (1994) and XP CEN/TS 15083-1 (2006). Padauk samples showed a high durability and very small variations between trees and within tree. Niove presented a high durability, but with notable differences according ...
Y N N’Kolo Meze’e, N Leménager, C Baudassé, M-F Thévenon
Measurements of rot fungal activity as a function of moisture content by isothermal calorimetry
2010 - IRG/WP 10-20428
Measurements of heat production rate have been made on wood samples with the brown rot fungus Postia placenta at different moisture contents. The results clearly indicate that the heat production rate (a measure of respiration rate and activity) is moisture dependent. When the moisture content is decreased, less heat is produced, and when the moisture content is increased, more heat is produced. I...
L Wadsö, A Pilgård, G Alfredsen
Profiling fungal community in wood decay ecosystem by Denaturing High-Performance Liquid Chromatography
2010 - IRG/WP 10-20443
A DNA-based fingerprinting technique, Denaturing High Performance Liquid Chromatography (DHPLC) was developed to profile fungal communities colonizing indoor timber. Molecular fungal diversity was assessed using amplification based on the Internal Transcribed Spacer (ITS1) rDNA of 74 wood samples collected from infected buildings in France. Due to its high sensitivity, the PCR-DHPLC technique was ...
S Maurice, G Le Floch, M Le Bras-Quéré, J P Rioult, G Barbier
Effects of polyvinyl alcohol on leachability and efficacy of boron wood preservatives against fungal decay and termites attack
2010 - IRG/WP 10-30526
In this study, the use of polyvinyl alcohol (PVA) as boron fixative agent was investigated. Two levels of PVA (2.5 and 4%) were evaluated with disodium octaborate tetrahydrate (DOT) at three concentrations (1, 2 and 4% boric acid equivalent (BAE) using a double vacuum impregnation processes on Scots pine sapwood specimens. Leaching was performed according to a laboratory leaching procedure. Boron ...
A Mohareb, M F Thévenon, E Wozniak, P Gérardin
Laboratory evaluation of borate amine: Copper derivatives in wood for fungal decay
2010 - IRG/WP 10-30543
The aims of this study were to evaluate borate: amine: copper derivatives in wood for fungal decay protection as well as the permanence of copper and boron in wood. Wood treated with each of four derivatives of borate:amine:copper prevented fungal decay. Disodium tetraborate ecahydrate (Borax):amine:copper derivatives with retentions of 0.61 to 0.63% after water leaching prevented decay by Gloeo...
G Chen
Preventing decay in termite monitoring stations
2010 - IRG/WP 10-30546
In-ground monitoring stations and termite baits are widely used in the southern United States with the intent of detecting and eradicating subterranean termite activity near buildings. These stations comprise a wood (or other cellulose material) substrate (monitor) and perhaps a termiticidal toxicant (bait) held in a plastic cage that allows for both easy examination and access by termites. The us...
A M Taylor, Jae-Woo Kim, S Duarte, L Nunes, J D Lloyd
Fungal decay resistance and mechanical properties of plywood panels made from maritime pine (Pinus pinaster) and bonded with cornstarch-quebracho tannin-phenol formaldehyde adhesive
2010 - IRG/WP 10-40490
The aim of this work is to demonstrate the performances of cornstarch-quebracho tannin-based resins designed as adhesive in the plywood production. In this way, the cornstarch and quebracho tannin was introduced in the classic adhesive formulation in order to supply a part of phenol-formaldehyde (PF). In order to evaluate the mechanical performances of optimal cornstarch-quebracho tannin-PF, plywo...
F Charrier, A Moubarik, A Allal, A Pizzi, B Charrier
Moisture dynamics of WPC as basis for biological durability
2010 - IRG/WP 10-40520
The largest market for wood-polymer composites (WPCs) is currently decking. Although many products are commercially available, a proper standard for the assessment of the biological durability of WPC does not exist. Recommended standards for testing resistance against basidiomycetes should be completed with a method to bring the specimens in a worst case situation, obtaining a moisture level high ...
N Defoirdt, J Van Acker, J Van den Bulcke
Fungal biodegradation of CCA-treated wood wastes
2011 - IRG/WP 10-50276
Fungal biodegradation could be employed as a pretreatment method to alleviate problems caused by landfill disposal of CCA-treated wood wastes (e.g. a shortage of landfill space and a release of leacheate). It could be used to decrease the volume of waste and to remove metals from waste simultaneously. We have screened hundreds of decay fungi, including fungi isolated from CCA-treated wood in servi...
Gyu-Hyeok Kim, Yong-Seok Choi, Jae-Jin Kim
Basidiomycete colonization of Scots pine sapwood quantified by qPCR and TGA
2011 - IRG/WP 11-10750
Scots pine (Pinus sylvestris L.) is an important softwood species in Northern Europe and is frequently used as material for various wood protection systems. In Europe, EN 113 is the standard basidiomycete laboratory durability test method, using mass loss as evaluation criteria. In this paper quantitative real-time PCR (qPCR) and thermogravimetric analysis (TGA) was used to characterize coloniza...
G Alfredsen, S Bollmus, T K Bader, K Hofstetter
Measuring fungal cellulolytic enzyme activity in degrading wood
2011 - IRG/WP 11-10753
An enzyme assay which measures enzyme activity directly from wood will assist in the fundamental understanding of the enzyme components of the decay mechanism of rot fungi and any changes in the presence of wood protectants. At present, to measure fungal carbohydrate degrading enzyme activity in the presence of wood, two methods are used: either 1) the enzyme is measured in the growth media contai...
S M Duncan, J S Schilling
Molecular investigation of Postia placenta growing in modified wood
2011 - IRG/WP 11-10756
Brown rot is the most common and destructive type of fungal decay for wood in service. These fungi depolymerize preferentially the structural carbohydrates, cellulose and hemicellulose in the cell wall leaving oxidized lignin behind. Modified wood can provide protection against a variety of wood deteriorating organisms, including decay fungi. However, there is still little known about the mode of ...
B Schmöllerl, G Alfredsen, C G Fossdal, M Westin, A Steitz
Growth conditions for fungal decay in wooden constructions – practical experience versus literature
2011 - IRG/WP 11-10758
Data regarding moisture and temperature requirements of decay fungi found in literature have been compared to experience from observations in a large number of Norwegian buildings. A number of selected situations are discussed, among those exposure to high relative humidity, exposure to free water and decay in the supposedly adverse conditions on Svalbard. The moisture content in wood has to be at...
M Sand Sivertsen, J Mattsson
The influence of moisture content and wood pH variation on fungal melanin formation in wood substrates
2011 - IRG/WP 11-10759
Wood decay patterns are strongly influenced by the conditions of the wood substrate, including moisture content and pH. In an antagonistic environment some fungi respond with pigment formation that helps to isolate and protect their mycelium. This is often associated with slower fungal growth and delay of wood mass loss. Dark colored melanin is the most common pigment formed by wood decay fungi, a...
D Tudor, S C Robinson, P A Cooper