Your search resulted in 49 documents. Displaying 25 entries per page.
Extracellular substance from the white rot basidiomycete Irpex lacteus involved in wood degradation
1992 - IRG/WP 92-1571
Cellulases, phenol oxidase, and a substance that both produced and reduced H2O2 were isolated from cultures containing wood or glucose on which the white-rot fungus Irpex lacteus was growing. The rate of wood degradation by the fungus with different amounts of glucose in the medium was measured. More of the substance that produced and reduced H2O2 was found extracellularly in cultures containing w...
H Tanaka, T Hirano, G Fuse, A Enoki
Characterisations of the mode of action(s) of Methylene bisthiocyanate (MBT) in Ophiostoma floccosum
2005 - IRG/WP 05-10554
Potassium (K+) leakage, oxygen consumption, glucose depletion and level of ATP formation were determined to elucidate the potential target site(s) of MBT on the sapstain fungus O. floccosum. Treatment of O. floccosum with MBT caused an efflux of intracellular K+ ions from the cells, and the rate of leakage increased with increasing MBT concentrations up to a certain value. This observation sugge...
T Singh, B Kreber, A Stewart, M Jaspers
The role of oxidation in wood degradation by brown-rot fung
1992 - IRG/WP 92-1562
Brown-rot fungi are suggested to degrade cellulose by oxidation with hydrogen radicalsformed eg. in the conversion of hydrogen peroxide in the Fenton type reactions. The stuctural changes in the holocellulose in wood induced by Fenton's reaction on wood components are very similar to those caused by brown-rot fungi. In this work the effect of the Fenton reaction on wood components was stu...
A-C Ritschkoff, J Pere, J Buchert, L Viikari
Mechanistic aspects of the reactions of copper complexes with lignin in the presence of hydrogen peroxide and lipid hydroperoxide model compounds as proposed for white rot fungi
2001 - IRG/WP 01-10399
The structural principles and the oxidative reactions of the catalytic system consisting of copper, hydroperoxides, and copper coordination compounds that contain aromatic nitrogen atoms are similar to those of catalytic centers of oxidative enzymes involved in delignification reactions of white rot fungi. The system is capable of selectively degrading lignin and its low molecular weight would all...
K Fackler, P Lamaipis, E Srebotnik, M Humar, C Tavzes, F Pohleven, M Sentjurc, T Watanabe, K Messner
Extracellular hydrogen peroxide-producing and one-electron oxidation system of brown-rot fungi
1990 - IRG/WP 1445
Wood-component-degrading compounds involved in the initial degradation of the cellulose and lignin in wood were isolated from wood-containing culture of brown-rot fungi, Gloeophyllum trabeum and Tyromyces palustris and partially purified by gel filtration on Sephadex G-25 and DEAE-Sepharose ion-exchange chromatography. The compounds were glycoproteins. The molecular weights of the glycoproteins as...
A Enoki, S Yoshioka, H Tanaka, G Fuse
Site characteristics impacting historic waterlogged wood: A review
2000 - IRG/WP 00-10344
Survival of waterlogged wood from hundreds and in rare cases millions of years presents scientists with a unique opportunity to examine wood specimens which, due to select properties of the wood itself and/or the depostional environment, have not been completely degraded. Although degradation patterns of various types of microbial wood decay have been studied in detail, the site parameters of the ...
B A Jordan, E L Schmidt
Experiments on the degradation of tributyltin oxide: A progress report
1984 - IRG/WP 3287
A variety of experiments designed to assess the chemical and physical factors affecting the degradation of tributyltin oxide in treated timber are described. Simple procedures in which temperature and oxygen availability were increased in the presence of wood and water suggest that the wood itself was of prime importance. Attempts to decrease degradation with antioxidants were unsuccessful but led...
R J Orsler, G E Holland
Collaborative soft rot tests: Statistical treatment of results of soil analyses
1971 - IRG/WP 29
Institutes taking part in the collaborative experiments already reported forwarded samples of the soils employed in the tests to the Forest Products Research Laboratory, England. The soils were then autoclaved sterilised under uniform conditions and sent to the Department of Forest Soils, the Royal College of Forestry, Stockholm, Sweden. The results of the soil analyses are given in Table 1, toget...
A F Bravery
Fluoride movement through Douglas-fir and hem-fir lumber following dipping in potassium/ammonium bifluoride
1995 - IRG/WP 95-40040
The ability of ammonium and potassium fluoride to diffuse through Douglas-fir and hem-fir lumber was evaluated over a 90 day period. Boards were dipped in a solution containing 10% (by weight) of ammonium and potassium bifluoride, then stored under cover for 90 days. Samples removed 30, 60 and 90 days after treatment indicated that the fluoride was unable to completely penetrate the wood. Penetrat...
J J Morrell, C S Love
In-house accelerated method for testing decay resistance of treated wood
2004 - IRG/WP 04-20286
Fungicidal compounds often change their effectiveness when they are incorporated into candidate formulations. For this reason fungistatic effectiveness needs to be re-evaluated as many times as the formula has been modified for better performance. To avoid multiple expenses, in-house fungistatic tests are essential. Our goal was to develop in-house usable, simple but reliable and reproductive proc...
N Vidovic
The production of extracellular hydrogen peroxide by some brown-rot fungi
1990 - IRG/WP 1446
The role of hydrogen peroxide (H2O2) has been discussed in the degradation of wood by wood-rotting fungi. The production of extracellular hydrogen peroxide was studied by detecting the oxidation of the chromogen 2,2'-azinobis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) by H2O2 and horse radish peroxidase (HPR). ABTS and HPR were added to a solid wood based culture media. In this study ...
A-C Ritschkoff, L Paajanen, L Viikari
Comparison of the inhibitory effects of borate, germanate, tellurate, arsenite and arsenate on 6-phosphogluconate dehydrogenase
1991 - IRG/WP 1508
Sodium borate inhibits the enzymatic activity of many dehydrogenases, and it is thought that this is due to the complexation of the borate anion with the coenzyme nucleotide. It has been suggested in the past that complexation of this type, leading to enzyme inhibition and other biological effects, is responsible for the inhibition of fungal growth and consequently the protection of boron treated ...
J D Lloyd, D J Dickinson
Detection of metabolic gas from termites using ceramic gas sensors
2001 - IRG/WP 01-20222
To evaluate termite attacks in wooden constructions by detecting the metabolic gas from termite colony, the basic performance of three types of ceramic gas sensors (odor-, methane- and hydrogen-selective sensors) was investigated. Four termite groups of different combinations of workers (100 to 1000) and soldiers (10 to 100) of Coptotermes formosanus Shiraki and a small specimen of Japanese red pi...
Y Yanase, Y Fujii, S Okumura, T Maekawa, K Suzuki, T Yoshimura, Y Imamura
Micromorphology of oak wood degraded by brown rot fungus Coniophora puteana
2000 - IRG/WP 00-10356
To characterize the degradation of hardwood by brown rot fungus, Coniophora puteana was incubated on the wood blocks of Quercus accutissima. For comparison, the same fungus was also incubated on the pine wood blocks of Pinus densiflora. In softwood, the shape of the wood cells and thickness of the cell appeared unchanged even the loss of birefringence in the affected areas. In contrast, oak wood d...
Yoon Soo Kim, Seung-Gon Wi, Kwang-Ho Lee
Wood preservation sites polluted by CCA. Is potassium diphosphate incubation a catalyst for the electrodialytic remediation of these soils?
1998 - IRG/WP 98-50106
As part of an evaluation of a newly developed electrodialytic soil remediation technique, we investigated the incubation of a contaminated soil (from a Portuguese wood preservation site polluted with CCA) with potassium diphosphate as a possible catalyst for the removal of heavy metals and metalloids. A chemical sequential extraction scheme (SE) applied to the soil has shown that the potassium dip...
A B Ribeiro, G Bech-Nielsen, A Villumsen, A Réfega, J Vieira e Silva
The effect of chitosan on the growth and physiology of two wood inhabiting fungi
2006 - IRG/WP 06-10590
The effect of chitosan on the wood inhabiting fungi Sphaeropsis sapinea and Trichoderma harzianum was evaluated at cellular level. Increasing concentrations of chitosan caused an increase in the amount of peroxide in cultures of S. sapinea, which was accompanied by a simultaneous decrease in superoxide. The same effect was not observed in T. harzianum. The growth of both fungi was inhibited when h...
D Vesentini, T Singh
Effect of fire retardants (monoammonium phosphate and diammonium phosphate, mixture of monoammonium phosphate and borax and ammonium sulphate) on beech wood with dipping and Lowry methods
2006 - IRG/WP 06-40350
In this study, the possibilities of using four kinds of chemicals as fire retardants with 12% concentration for beechwood (Fagus orientalis Lipsky) was surveyed. Providing testing samples that are related to the measurement of fire resistance properties according to JIS A-1321-1975 standard were evaluated. Wood samples were impregnated with Lowry and dipping methods. In this study, samples impregn...
M Akhtari, D Parsapajouh, M Arefkhani
Effect of fire retardants (monoammonium phosphate and diammonium phosphate, mixture of monoammonium phosphate and borax and ammonium sulphate) on beech wood with dipping and Lowry methods
2006 - IRG/WP 06-40350
In this study, the possibilities of using four kinds of chemicals as fire retardants with 12% concentration for beechwood (Fagus orientalis Lipsky) was surveyed. Providing testing samples that are related to the measurement of fire resistance properties according to JIS A-1321-1975 standard were evaluated. Wood samples were impregnated with Lowry and dipping methods. In this study, samples impregn...
M Akhtari, D Parsapajouh, M Arefkhani
Effects of bleaching process on the roughness values of wood surfaces of Lebanon cedar (Cedrus libani A. Rich.) and Black poplar (Populus nigra L.) using NaOH (sodium hydroxide), H2O2 (hydrogen peroxide) and Ca(OH)2 (calcium hydroxide)
2008 - IRG/WP 08-40403
Technical progress in the wood industry has been rapid in recent times. In this case, the quality assurance of the consumer products aligned with aesthetics value appears as one of the most important parameters. Because of the outer appearance of goods exert an effect on customers, interest in production of high quality surfaces of wooden commodities has increased essentially based on the surface ...
I Usta, E Aydinlar
Degradation of wood veneers by Fenton’s reagents: effects of low molecular weight phenolic compounds on hydrogen peroxide decay and tensile strength loss
2009 - IRG/WP 09-20400
Pine wood (Pinus sylvestris) veneers strips were incubated in acetate buffer containing hydrogen peroxide and iron to mimic mechanisms of brown rot decay and assess the degradation of cellulose through analysis of the tensile properties of the decayed wood. The tensile properties of thin wood strips treated with Fenton system reagents or precursors were determined and correlated to weight loss as ...
Yanjun Xie, R Well, Zefang Xiao, B Goodell, J Jellison, H Militz, C Mai
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
Fire resistance of wood treated with potassium carbonate and silanes
2014 - IRG/WP 14-30657
This paper reports on the effect that organosilicon compounds and potassium carbonate and urea (PCU) have on wood flammability. The study focus on reducing wood flammability by promoting char formation through manipulation of the condensed phase decomposition chemistry. Potassium carbonate is known as an effective fire retardant, however it is easily leached out from wood and increases its hygrosc...
B Mazela, M Broda, W Perdoch
Bio-friendly preservative systems for enhanced wood durability - the first periodic report on DURAWOOD
2015 - IRG/WP 15-30677
The objective of the paper is the DURAWOOD scientific project carried out within Polish-Norwegian Research Programme, which lasts from September 2013 till August 2016. The aim of the project concentrates on the developing of a new, eco-friendly and biocide-free wood protective systems as an alternative to traditional, commonly used preservatives or coatings, containing biocides. Several wood prese...
B Mazela, M Broda, W Perdoch, L Ross Gobakken, I Ratajczak, G Cofta, W Grześkowiak, A Komasa, A Przybył
Study on the Effects of Flame Retardant in Dancheong for Korea Wooden Cultural Heritage
2015 - IRG/WP 15-40692
This study identifies the effect of the agent depending on environment change and conducted basic study to prepare criteria for stable application. Dancheong sample, which is similar to wooden cultural heritage, was manufactured to study the effect of the agent on dancheong. Regular observation on the samples located in inland and shoreline area in the country detected visible phenomena. Whitening...
Hwa Soo Lee, So Jung Lee, Gyu Seong Han, Yong Jae Chung