Your search resulted in 1665 documents. Displaying 25 entries per page.
The effect of low molecular weight chelators on iron chelation and free radical generation as studied by ESR measurement
2000 - IRG/WP 00-10367
The focus of this work was to improve our current knowledge of the non-enzymatic mechanisms involved in brown-rot decay. Electron Spin Resonance (ESR), also known as Electron Paramagnetic Resonance (EPR), is an attractive technique for the identification and study of chemical species containing unpaired electrons (such as radicals and certain transition metal species). ESR spin-trapping techniques...
Yuhui Qian, B Goodell
Influence of variable lignin content on brown rot decay of wood
1987 - IRG/WP 1320
Compilation of published data and new experiments with brown-rotting fungi on different timber species suggest that their decay activity, in contrast to soft rot and white rot fungi, is not greatly influenced by the type or amount of lignin present....
T Nilsson, G F Daniel
Defining fungal decay types - Final proposal
1988 - IRG/WP 1355
The term soft rot is proposed for all forms of decay caused by Ascomycetes and non-basidiomyceteous Fungi imperfecti. The terms brown rot and white rot should be used only for decay caused by Basidiomycetes. Brown rot is characterized by extensive depolymerization of the cellulose and limited lignin degradation. White rot is characterised by significant degradation of the lignin component in wood....
T Nilsson
Comparison of the effect of different soil sources on the type and rate of decay of CCA-treated pine exposed in a soil-bed
1984 - IRG/WP 2213
The types of decay observed in CCA-treated pine posts in horticultural situations in New Zealand can be reproduced using a soil-bed exposure. Radiata pine stakelets, untreated or treated to 1.4, 2.7, or 5.4 kg/m³ with Tanalith NCA, were exposed to six different soil sources. The local nursery soil used for all standard laboratory tests was found to represent the greatest decay hazard to untreated...
J A Drysdale
Importance of bacteria in the deterioration of archaeological woods
1995 - IRG/WP 95-10122
An electron microscopic study of archaeological woods from different sites and of different ages revealed that the woods had been attacked by erosion bacteria, tunnelling bacteria and soft rot fungi. Bacterial erosion appeared to be most widespread, and was present independently as well as together with tunnelling and soft rot attacks. Thus, in many instances bacterial erosion was the only type of...
Yoon Soo Kim, A P Singh, T Nilsson
Biological resistance of phenol-resin treated wood
1990 - IRG/WP 3602
Biological resistance of PF (phenol formaldehyde resin) - treated wood has been tested in relation to the resin properties, wood species and biological factors. When tested using water-soluble PF (mol. wt. 170), ca. 10% RI (resin impregnation) was enough to suppress the decay of Japanese cedar (Cryptomeria japonica) and western hemlock (Tsuga heterophylla) blocks exposed to Tyromyces palustris (br...
M Takahashi, Y Imamura
Suppression of aerial hypha formation by spent culture filtrate of a non-degradative strain of Postia placenta
1991 - IRG/WP 1498
ME20, a wild-type monokaryotic strain of the brown-rot fungus Postia placenta, does not cause significant weight losses in standard soil-wood block decay tests and fails to form aerial hyphae in liquid and agar culture. This abnormal morphological feature may be caused by the same aberrant physiology that prevents the strain from degrading wood efficiently. ME20 releases elevated levels of the aut...
J A Micales
Wood degradation mechanisms by the brown rot fungus Gloeophyllum trabeum
1997 - IRG/WP 97-10229
A mechanism for the degradation of wood by the brown rot fungus Gloeophyllum trabeum is outlined. The mechanism includes the function of redox-cycling, low molecular weight phenolic derivatives which sequester and reduce iron in acidic environments. The role of oxalate for the sequestration of iron (hydr)oxides and the pH dependent transfer of iron to the G. trabeum phenolic chelators, as well as ...
B Goodell, J Jellison
Analysis of degradation observed on ancient wooden objects buried underground
2001 - IRG/WP 01-10403
Ancient wooden objects were sometimes excavated from the moat of mounded tombs in Japan. Such wooden objects were in the shape of a sunshade, bird, shield, pole, yugi(a bag that holds arrows) among others. Archaeologists discussed the usage of such shaped objects, but no one could clearly explain their use. Some objects were observed using an ordinary microscope. Deterioration by bacteria was foun...
H Sakai
Copper-resistant fungi on pressure impregnated wood in Denmark
1994 - IRG/WP 94-10078
The occurence of Amorphotheca resinae Parbery and its asexual stage Cladosporium resinae (Lindau) de Vries on CCA and CCB treated wood has previously been shown. In the autumn 1993 some other blue stain fungi were found on CCP and CCB treated pine timber, such as Ophiostoma minus (Hedgc.) H. and P. Sydow, Ophiostoma pilifera (Fr.) H. and P. Sydow and Ophiostona piceae (Munch) H. and P. Sydow. The ...
J Bech-Andersen, S A Elborne
Decay types observed in small stakes of pine and Alstonia scholaris inserted in different types of unsterile soil
1990 - IRG/WP 1443
The attack of various wood-degrading microorganisms occurring in mini-stakes of pine and Alstonia scholaris buried in various types of unsterile soil was studied. Attacks by white rot, brown rot, soft rot, erosion bacteria, tunnelling bacteria and actinomycetes were found. Soft rot occurred in all soils, whereas attack by white rot and especially brown rot and erosion bacteria was rare. The type o...
T Nilsson, G F Daniel
Soft rot fungi as possible sources of odor in impregnated wood in buildings
1993 - IRG/WP 93-20013
Wood preservatives are frequently used inside houses. In several cases impregnated wood, particularly when used in crawlspaces or other near-ground constructions, has been found to be a source of odor. Mold fungi, soft rot fungi actinomycetes or bacteria growing on impregnated wood are possible producers of the odor. Analyses of volatile emissions from impregnated wood with odor and pure cultures ...
J Bjurman, J Kristensson
Effect of light and ventilation condition on the rate of wood decay by the brown rot basidiomycete, Tyromyces palustris
1991 - IRG/WP 1517
Effect of light and the ventilation conditions of incubation jars on the wood decay by Tyromyces palustris (Berk. et Curt.) Murr. FFPRI 0507 was investigated. Under no irradiation of light, the ventilation conditions gave extensive effect on mass loss of the test pieces when the culturing was performed with culture medium designated in Japanese Industrial Standard (JIS) A 9302 (Medium A; glucose 4...
T Suzuki, M Higaki
Bioassays for rapid assessment of heavy metal toxicity in seawater
1998 - IRG/WP 98-50112
In evaluating the effect of CCA leachate on the establishment of fouling communities on wood exposed in the sea, three organisms were assessed as biological indicators of heavy metal toxicity. These were two macroalgae, Fucus serratus and Undaria pinnatifida. and the motile protist thraustochytrid, Schizochytrium aggregatum. The choice of these organisms for the tests carried out was based on the ...
C J Brown, R L Fletcher, R A Eaton
The performance of CCA treatment in bamboo against decay fungi
1993 - IRG/WP 93-30027
Samples of culm wall material from young (< 6 month age) and mature (> 3 years age) culms of the bamboo, Phyllostachys virideglaucescens were treated to equivalent% w/w retentions of a CCA preservative. After fixation and leaching the treated samples were exposed to decay by Chaetomium globosum FPRL S70K, Coriolus versicolor FPRL 28A and Coniophora puteana FPRL 11E. Thin section samples of u...
O Sulaiman, R J Murphy
Screening of lignin peroxidase from white-rot fungi
1998 - IRG/WP 98-10274
Since lignin peroxidase was first found in the ligninolytic culture of Phanerochaete chrysosporium, it has been regarded as an enzyme responsible for the lignin biodegradation and studied comprehensively. As the results of these studies its unique characteristics have been revealed. On the other hand, the features of lignin peroxidase produced by other white-rot fungi have not been studied so much...
I Momohara
Oxalate production and calcium oxalate accumulation by Gloeophyllum trabeum in buffered cultures
1994 - IRG/WP 94-10075
Most basidiomycetous fungi produce oxalic acid as a result of their metabolic activities and nutrient procurement. There is currently a renewed interest in the role that oxalic acid may play in the decomposition of wood by basidiomycete fungi. It has been observed that although most wood degrading fungi have the capacity to produce oxalic acid, not all of these organisms express this capacity equa...
J H Connolly, J Jellison
Soft rot studies on CCA treated eucalypt power transmission poles
1981 - IRG/WP 1132
Initial results found for sixty CCA treated eucalypt poles, from a soft-rot survey are discussed. Retentions of CCA within above and below ground pole samples were variable. The variation was attributed mostly to biodegradation and effect of soil environment, rather than leaching. Bacterial decay was found in many poles and was severe in some cases. Although found in the presence of soft-rot decay...
L E Leightley
Identification of terminal structures in cellulose degraded by the brown-rot fungus Postia placenta
1989 - IRG/WP 1389
To gain insight into the biochemical mechanism employed by brown-rot fungi to depolymerize cellulose, we identified the end-groups of chemically pure cellulose that had been depolymerized by the brown-rot fungus, Postia placenta. The depolymerized cellulose was acid hydrolyzed and the anion fractions isolated by ion chromatography. Sugar acids were identified by gas chromatographic and mass spectr...
T K Kirk, T L Highley, R E Ibach, M D Mozuch
Biosynthesis of ß-Glucan microfibrils by cellular fractions from brown-rot fungus Postia placenta (MAD-698 and ME-20) and white-rot fungus Schizophyllum commune (MAD-619)
1993 - IRG/WP 93-10025
In this study, we compared the brown rot fungus Postia placenta (MAD-698 and ME-20) with the white rot fungus Schizophyllum commune (MAD-619) to determine the location and distribution of glucan synthetase. We also measured the soluble protein content in subcellular fractions obtained by differential centrifugation MAD-698 is a degradative isolate, but ME-20 and MAD-619 do not produce significant ...
S C Croan, T L Highley
Evaluation of substituted isothiazolone as a potential new wood preservative
1984 - IRG/WP 3306
Laboratory decay tests were carried out with isothiazolone (4,5-dichloro-2-n-octyl-4-isothiazolone-3-one) treated wood. This compound was found to be extremely effective against three common wood decaying brown-rot fungi, exhibiting toxic threshold values in the range of 0.37 to 0.50 kg/m³. For the white-rot fungus, Coriolus versicolor, the toxic threshold values for treated pine and sweetgum wer...
D D Nicholas, A F Preston, D E Greenley, S V Parikh
Fungus cellar testing as an evaluation method for performance of treated timber in ground contact
2001 - IRG/WP 01-20227
A fungus cellar method for the accelerated evaluation of performance of treated wood in ground contact is described. The test soil comprised of sandy loam, vermiculite and Japanese horticulture soil "Kanumatsuchi" in a ratio of 6:2:2 by volume. The soil was inoculated with the dominant test fungus isolated with selective medium from decayed wood samples. Pairs of treated and untreated wood specime...
Y Nagano
Natural durability transfer from sawmill residues of white cypress (Callitris glaucophylla). - Part 2: Laboratory fungal bioassays
2000 - IRG/WP 00-20204
Extracts from sawmill residues of the naturally durable white cypress, Callitris glaucophylla were tested for fungicidal activity in a series of laboratory bioassays. The effects of different extraction solvents, techniques and sources of material on the biocidal efficacy of the resultant extracts were evaluated. Soil jar decay tests were used initially however, contractual time constraints necess...
M A Powell, L M Stephens, L Francis, M J Kennedy
An electron spin resonance study of manganese changes in wood decayed by the brown-rot fungus, Postia placenta
1988 - IRG/WP 1359
Electron spin resonance (ESR) spectrometry was used to examine wood decay by the brown-rot fungus, Postia placenta. Wood slivers of Douglas-fir, white fir, redwood, sweetgum and yellow poplar were incubated for 4 weeks in custom-made quartz ESR tubes with or without Postia placenta. In all wood species without fungus, a weak partially resolved signal (about g=2, presumably due to manganese) was de...
B Illman, D C Meinholtz, T L Highley
The effect of hemicellulose degradation on the mechanical properties of wood during brown rot decay
2001 - IRG/WP 01-20219
Incipient decay of wood by brown rot fungi causes measurable strength losses in wood before measurable weight loss occurs. Previous studies have shown that the high levels of strength loss that occur during incipient brown rot decay may be related to loss in hemicellulose. This paper investigates the effect of decay on hemicellulose composition and the relationship to the mechanical properties of ...
S F Curling, C A Clausen, J E Winandy