Your search resulted in 697 documents. Displaying 25 entries per page.
The dry rot fungus and other fungi in houses. Part 2
1993 - IRG/WP 93-10001
Cytochemical localization of hydrogen peroxide in brown rot fungus Tyromyces palustris by cerium chloride technique
1999 - IRG/WP 99-10299
Cerium chloride (CeCl3) was used to localize H2O2 cytochemically for studying relationship between ultrastructural and functional characteristics of cellulose degradation by brown rot fungi. This technique proved very useful in localizing discrete electron-densereactionproducts at high resolution with minimal nonspecific deposition. The cytochemical localization of extracellular H2O2 by CeCl3 usin...
Yoon Soo Kim, Seung-Gon Wi
Localization of oxalate decarboxylase in the brown-rot fungus Postia placenta
1996 - IRG/WP 96-10161
Oxalate decarboxylase, the enzyme that breaks oxalic acid down into formic acid and carbon dioxide, was recently detected in mycelial extracts of the brown-rot fungus Postia placenta. Differential centrifugation was used to demonstrate that the enzyme is loosely associated with the hyphal surface. Enzyme activity can be removed by washing the hyphae with a low pH buffer. Only low levels of activit...
J A Micales
Conditions for basidiospore production in the brown rot fungus Gloeophyllum separium in axenic culture
1984 - IRG/WP 1232
Attempts to control and optimize the production of hymenial structures and basidiospore production in Gloeophyllum sepiarium in axenic culture resulted in the proposal of the following conditions as being suitable. The dikaryotic mycelia originally isolated from basidiocarps could consistently be induced to produce hymenial structures and pure basidiospore collects if illuminated by near ultraviol...
Removal of heavy metals from treated wood using biological methods
2005 - IRG/WP 05-50226
Heavy metals were removed from wood treated with copper based preservatives using brown-rot fungus Fomitopsis palustris. The amount of effective elements removed by treatment methods was examined. The relationship between oxalic acid concentration and the amount of heavy metals removed from each treated wood was also investigated. The relationship between fungus weight and removal rate was also in...
Dong-won Son, Dong-heub Lee
The preliminary characterization of ß-1,4-xylanase of the brown-rot fungus Gloeophyllum trabeum
1990 - IRG/WP 1447
The extracellular ß-1,4-xylanase of the brown-rot fungus, Gloeophyllum trabeum, was isolated from crude extract by chromatofocusing method (PBE 94 column chromatography). The isoelectric point was estimated to 4.2-4.8 by cromatofocusing and 4.5 by isoelectric focusing (IEF). The molecular weight of the enzyme was estimated to 37,000 dalton by SDS-PAGE. The optimal temperature for the crude extrac...
A-C Ritschkoff, M Rättö, L Viikari
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
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
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
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 critical moisture and temperature conditions for the growth of some mould fungi and the brown rot fungus Coniophora puteana on wood
1988 - IRG/WP 1369
The growth of some mould fungi on pine and spruce sapwood was studied in 40 different constant moisture and temperature conditions. The temperature range was between +10 and +40°C and the relative humidities varied from 76 to 100% relative humidity (RH). The incubation time was 12 weeks. The mixed mould inoculation used included typical fungi growing on wood: Aspergillus versicolor, Cladosporium ...
H Viitanen, L Paajanen
Generation of hydroxyl radical by the brown-rot fungus, Postia placenta
1988 - IRG/WP 1360
In an electron spin resonance (ESR) survey of various liquid cultures and wood slivers innoculated with the brown-rot fungus, Postia placenta, the spin trap dimethyl-l-pyrroline N-oxide (DMPO) was used to detect the presence of the hydroxyl radical. The ESR spectra for the paramagnetic DMPO- hydroxyl radical adduct was observed in (1) nitrogen-limited, liquid cultures having 1.0% glucose or 0.1% c...
B Illman, D C Meinholtz, T L Highley
Preservative effect of cellulose insulation material against some mould fungi and brown rot fungus Coniophora puteana in pine sapwood
1991 - IRG/WP 1484
The influence of mineral wool and loose-fill cellulose wool on biodeterioration of pine sapwood was studied. The test fungi were mould fungi Aspergillus versicolor, Cladosporium sphaerospermum, Penicillium sp. and Aureobasidium pullullans and brown rot fungus Coniophora puteana. Cellulose wool inhibited the growth of mould fungi on the face of wood contacted with insulation material at RH of 97 an...
Oxalic acid quantification, oxaloacetase assay and ESI localization of P, C, and Fe from the brown rot fungus Postia placenta
1994 - IRG/WP 94-10063
The mechanism by which brown-rot fungi initiate depolymerization of holocellulose in wood remains unknown. Recently, oxalic acid (OA) has received considerable attention in cellulose breakdown by brown-rot fungi. The OA could serve as a proton donor for hydrolytic or an electron donor for oxidative (Fenton's reaction-H2O2/Fe2+) cleavages of cellulose. The acid may originate via oxaloaceta...
C R Jordan, W V Dashek, T L Highley
Proposed model for the penetration and decay of wood by the hyphal sheath of the brown-rot fungus Postia placenta
1989 - IRG/WP 1391
Scanning electron microscopy (SEM) of Pinus sp. decayed by the brown-rot fungus Postia placenta confirmed the existence of extracellular membranous structures previously described by transmission electron microscopy (TEM). These structures appear to be an integral part of the hyphal sheath and assume a variety of forms including lamellar sheets, fibrils, and vesicles. These structures were observe...
F Green III, M J Larsen, L L Murmanis, T L Highley
Production of exraxellular hydrogen peroxide and oxalic acid by brown-rot fungus Poria placenta
1995 - IRG/WP 95-10112
Hydrogen peroxide and oxalic acid have been suggested to be essential in the degradation of wood carbohydrates by brown-rot fungi. Hydrogen peroxide has been suggested to be one of the diffusible low molecular weight agents produced by brown-rot fungi for the degradation of wood carbohydrates by generating highly active radicals. The production of hydrogen peroxide and oxalic acid by Poria placent...
A-C Ritschkoff, M Rättö, J Buchert, L Viikari
Detection of a brown-rot fungus using serological assays
1986 - IRG/WP 1305
Polyclonal antisera produced to Poria placenta (Fr.) Cooke were used in two tests to qualitatively assay for the fungus. Fungal hyphae were fixed to slides and fluorescent antibody (FA) techniques used to visualize the hyphae under the microscope. Fluorescence of non-Poria fungi, when present, could be reduced but not eliminated by cross-absorbing the sera with these fungi. The antisera was also u...
B Goodell, J Jellison
Immuno-electron microscopic localization of extracellular metabolites in spruce wood decayed by brown-rot fungus Postia placenta
1990 - IRG/WP 1441
Degradation by Postia placenta in spruce and birch wood was shown to occur not only in the wood cell wall but also in the middle lamellae region. Middle lamellae was often found to be degraded along the centerline so that cells could separate along this line. Extracellular membrane structures were found surrounding the hyphae and this matrix labelled positively with antisera produced to Postia pla...
Y S Kim, B Goodell, J Jellison
The Effect on Biological and Moisture Resistance of Epichlorohydrin Chemically Modified Wood
2002 - IRG/WP 02-40224
Southern pine solid wood and fiber were chemically modified with epichlorohydrin to help in understanding the role of moisture in the mechanism of biological effectiveness of chemically modified wood. The solid wood had weight gains from 11% to 34%, while the fiber had weight gains from 9% to 75%. After modification, part of the specimens were water leached for 2 weeks or extracted for 2 hours ...
R E Ibach, B-G Lee
Properties of cellulose degraded by the brown rot fungus, Postia placenta
1988 - IRG/WP 1350
To gain further understanding of the nature of the cellulose depolymerizing agent or agents of brown-rot fungi, brown-rotted cellulose was chemically and physically characterized. Various culture conditions, such as low nitrogen and elevated oxygen levels, did not induce degradation of cellulose by Postia placenta in liquid cultures. Therefore, brown-rotted cellulose for analysis was prepared by a...
T L Highley, R E Ibach, T K Kirk
Growth of the copper tolerant brown rot fungus Antrodia vaillantii on different substrates
1995 - IRG/WP 95-10121
In recent years the copper tolerant brown rot fungus Antrodia vaillantii caused severe damages on impregnated wood in ground contact. The pattern of decay gave the impression that impregnated wood was even more severely attacked than unimpregnated. To investigate this question more closely laboratory tests were carried out. In a "choice test" Antrodia vaillantii grew preferably towards CC-impregna...
H Leithoff, I Stephan, M-T Lenz, R-D Peek
Decay resistance of Siberian larch wood against brown rot fungus. - Part 3. The variation between plus trees and their grafted clones
2000 - IRG/WP 00-10350
The aim of the study was to estimate the variation in the decay resistance of Siberian larch (Larix sibirica Ledeb.) wood using mature plus trees and their grafted clones. Samples were collected with an increment core borer from 11 original plus trees and their 25-year-old grafted seed orchard clones. A typical brown rot fungus, Coniophora puteana (Schum. ex Fr.) Karst. (BAM Ebw. 15), was used as ...
H Viitanen, L Paajanen, M Venäläinen, A Harju, P Velling
Solid state NMR study on pine wood degraded by brown rot fungus Gloeophyllum trabeum
1994 - IRG/WP 94-10067
Blocks of Pinus koraiensis wood were degraded by Gloeophyllum trabeum and examined by solid-state 13C NMR spectroscopy. Chemical compositions were estimated from relative signal aras. There was no evidence for preferential degradation of the noncrystalline cellulose which accounted for about 4% by weight of the wood. Loss of partly ordered cellulose on crystal surfaces exceeded the loss of crystal...
Yoon Soo Kim, R Newman
New ways of chemical wood preservation
1997 - IRG/WP 97-40087
Synergistic effects pertaining to wood preservation have been investigated by combining different polymerizing agents with modifying chemicals, modifying chemicals with known preservatives and new types of preservative chemicals with each other. One of the investigated methods is the use of impregnating solutions based on furfuryl alcohol (produced from biomass), in which the chemicals polymerizes...
M Westin, T Nilsson, B Ohlsson, R Simonson