Your search resulted in 1091 documents. Displaying 25 entries per page.
Comparative study of lignocellulolytic activities of Pleurotus spp. and white rot and brown-rot fungi
1997 - IRG/WP 97-10210
In this work, the in vitro species of Pleurotus (P.eringii, P. cornucopiae and P. ostreatus), from structures of degraded wood have been studied. This degradative activity was compared to those presented by Trametes versicolor (fungus characteristic of white rot) and Gloeophyllum trabeum (fungus representative of brown rot). The activities studied were the following: cellulase, xylanase, pectinase...
D Muñoz-Mingarro, F Llinares, M T De Troya, F Rubio, M Yuste, C Rodríguez-Borrajo, J E Garcia de los Rios, F Alvarez, P Jiménez, A Rojas, A Navarrete, P Reche
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
Early detection of brown-rot decay in southern yellow pine using immunodiagnostic procedures
1990 - IRG/WP 2356
Immunodiagnostic procedures have been used to detect incipient decay of southern yellow pine by six common brown-rot fungi. Rabbit polyclonal antibodies were raised to liquid culture fractions of the six fungi. The antibodies, after preadsorption to sawdust, were tested in particle agglutination assays, immuno-dot blot, and ELISA for their·ability to detect the decay organisms when they were grow...
C A Clausen, F Green III, T L Highley
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
Preservative ability of wood to be fixed hydroxyl apatite substituted for antimicrobial metals
2001 - IRG/WP 01-30272
We succeeded in forming hydroxy apatite (HAp) in wood. HAp is non-toxicity and safe. Preservative ability of the wood, which substituted one part of Ca of constituent element of this HA p for antibacterial metals was measured. When Ca was substituted for Ag or Zn, mass loss in decay by brown-rot fungus F. palustris was restrained in about 50% (Ag) ~30% (Zn) of value of control specimen. However, w...
Y Haruhiko, I Sumaru
Influence of CCA and TnBTO on wood decay, under different oxygen levels and various initial moisture content
2001 - IRG/WP 01-10415
Fagus sylvatica (beech) and Pinus sylvestris (Scots pine) were impregnated by TnBTO (tributyl-tin oxide) and CCA (chromated copper arsenate). In wood blocks two levels of moisture content (50% and 100% of saturation point) were used. Three levels of oxygen concentrations (10, 21, and 50%) were chosen. Treated and untreated wood were exposed to three fungi (C. versicolor a white rot, C. puteana, a ...
S M Kazemi, R J Murphy, D J Dickinson
Resistance of acetylated wood to basidiomycetes, soft rot and blue stain
1994 - IRG/WP 94-40021
Poplar (Populus spp.), beech (Fagus sylvatica) and pine sapwood (Pinus sylvestris) samples were acetylated in a semi-industrial acetylation plant and tested for durability according to European standards. Resistance to Gloeophyllum trabeum, Coniophora puteana and Coriolus versicolor could be reached at a weight percent gain (WPG) of 12%. Susceptibility of acetylated pine to Poria placenta was high...
E P J Beckers, H Militz, M Stevens
Extracellular hydrogen peroxide producing and hydrogen peroxide reducing compounds of wood decay fungi
1991 - IRG/WP 1516
Extracellular H2O2-producing and H2O2-reducing compounds were isolated from wood-containing cultures of all the white-rot and brown-rot fungi and Ascomycetes which well degraded wood, but were not detected in the culture of the fungi which degraded little wood. The compounds are glycopeptides with a low molecular weight, require H2O2 for one-electron oxidation, catalyze the redox reaction between ...
A Enoki, G Fuse, H Tanaka
Control of sapwood-inhabiting fungi by fractionated extracellular metabolites from Coniophora puteana
1991 - IRG/WP 1494
The objective of this study was to test the fractionated metabolites released by Coniophora puteana for their antagonistic activity against the sapstain fungi Ceratocystis coerulescens and Aureobasidum pullulans, and the molds Asperigillus niger and Penicillium spp. The acetone-soluble fraction obtained from the culture filtrate prepared from Coniophora puteana grown on 6% malt extract agar inhibi...
S C Croan, T L Highley
Dimensional lumber model demonstrates the sensitivity of the particle capture immunoassay in early detection of brown-rot fungi
1995 - IRG/WP 95-20058
A dimensional lumber model was designed to test the sensitivity of the particle capture immunoassay (PCI) compared to traditional methods of culturing and microscopic examination for detection of brown-rot fungi. Southern yellow pine 2 x 4's (5.1x10.2 cm²), and 86.4 cm in length, were inoculated on one end with the brown-rot fungus, Postia placenta, and tested over the full length of the...
C A Clausen, L Ferge
Detection of brown-rot antigens in southern pine
1996 - IRG/WP 96-20090
Brown rot fungal antigens were detected by particle capture immunoassay (PCI) in southern pine 2 x 4's beyond visible or culturable hyphal growth. Further analysis of test samples revealed changes along the 2 x 4's that could be grouped into zones. Zone 1, the point of inoculation through 6 cm, showed low pH, measurable oxalic acid, high moisture, and high protein. Zone 2, throug...
C A Clausen
Hemicellulosic induction of oxalic acid in Postia placenta
1994 - IRG/WP 94-10060
Most studies suggest that enzymes produced by brown-rot fungi are too large to penetrate sound wood structures, even after decay begins. Thus, nonenzymatic agents have been proposed to initiate brown-rot decay. We have reported that the brown-rot fungus Postia placenta MAD-698 initiates a 2-fold decrease in wood pH within 7 days of colonization which is mediated by production of oxalic acid. Strai...
F Green III, M Larsen, T L Highley
Decay resistance of Platanus acerifolia wood against White Rot Fungi (Coriolus versicolor)
2002 - IRG/WP 02-10431
Degradation of the lignocellulose complex in wood varies on the microorganism causing decay and chemical composition of wood. The weight loss of Platanus acerifolia wood after decay by white rot fungus (Coriolus versicolor) for period 16 weeks were evaluated according to European standard EN 113 and beech wood as a control. The samples were collected in October 2000 from Nantes, France. The aim of...
M Irmouli, O Duchelier, N Ayadi, B Charrier
The long road to understanding brown-rot decay. A view from the ditch
1995 - IRG/WP 95-10101
Interest in understanding how brown-rot fungi decay wood has received increasing interest in recent years because of a need to identify novel targets that can be inhibited for the next generation of antifungal wood preservatives. Brown-rot fungi are unique in that they can degrade holocellulose (cellulose and hemicellulose) in wood without first removing the lignin. Furthermore, they degrade holoc...
F Green III, T L Highley
Is laboratory testing of decay resistance questionable as a single criterion for natural durability?
1996 - IRG/WP 96-20096
In a laboratory test set up over 20 hardwood species were evaluated according to the European Standard EN 350-1 including Basidiomycete and soft rot testing. Half of the species used were of a known natural durability. The Basidiomycete testing was carried out using Coriolus versicolor, Gloeophyllum trabeum and Coniophora puteana in a malt agar test similar to EN 113. From this test it was not pos...
J Van Acker, M Stevens, T Van Cauwenberghe, T Seynaeve
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
Targeted inhibition of wood decay (Using everything but the kitchen sink)
1997 - IRG/WP 97-10203
Low molecular weight oxidative decay agents have been implicated in the degradation of wood by brown-rot decay as evidenced by chemical analysis of brown-rotted wood and detection of oxalic acid and hydroxy radicals. Fenton chemistry (H2O2 / Fe++) is often proposed as the mechanism for generating hydroxy radicals. Previous authors have shown iron to enhance the brown-rot hydrolysis of wood, while ...
F Green III, T A Kuster, T L Highley
The biological effectiveness of wood modified with heptadecenylsuccinic anhydride against two brown rot fungi: Coniophora puteana and Gloeophyllum trabeum
1992 - IRG/WP 92-3705
A modified soil block test was carried out using wood samples reacted with heptadecenylsuccinic anhydride (ASA). This modification gave good resistance to decay brought about by the brown rot fungi Coniophora puteana and Gloeophyllum trabeum during the twelve week exposure period. Results indicated that there was a good correlation between increased loading of modifying reagent and an increase in ...
C Codd, W B Banks, J A Cornfield, G R Williams
Utilization of coconut timber from north Sulawesi, Indonesia. Part 1: Durability
1994 - IRG/WP 94-30044
Coconut timber from non-productive plantations is a byproduct of an agricultural crop and, by the same token, constitutes a renewable resource which may serve as a complement to or, at least in part, as a substitute for traditional timbers in local markets. Its more extensive utilization is expected to contribute to the conservation of tropical rain forests. Export of coconut timber and/or wood pr...
R-D Peek
Premature failure of CCA treated vineyard posts from brown rot
1993 - IRG/WP 93-10016
A survey of CCA (AWPA Type C) treated posts used as grape vine trellis supports, to determine the extent and type of decay was carried out at a terraced vineyard in the Hawkes Bay region of the North Island of New Zealand. Of 357 posts examined out of a total of 970 in the vineyard, 47% had moderate to severe decay or had failed, 20% had established decay, 10% had a trace of decay and 23% had no s...
R N Wakeling, A P Singh
Relationship between degradation of wood, cellulose or lignin-related compounds and production of hydroxyl radical or accumulation of oxalic acid in cultures of brown-rot fungi
1994 - IRG/WP 94-10062
The degradation activities of brown rot fungi against wood, cellulose, and lignin-related compounds were measured in cultures containing glucose or wood as a carbon source. Also the activities of one-electron oxidation and hydroxyl radical production and the amount of oxalic acid present in the cultures were measured. The degradation activities of the fungi against wood, crystalline cellulose and ...
S Itakura, T Hirano, H Tanaka, A Enoki
Lab and field test results for wood treated with polymeric alkylphenol polysulfide
2001 - IRG/WP 01-30268
A new wood preservative based on polymeric alkyphenol polysulfide (PXTS-A) is being evaluated in a series of laboratory and field tests and the results continue to show promise. A modified formulation (PXTS-B), which contains additives to reduce the viscosity, is being evaluated along with the original formulation. Soil block decay tests comparing PXTS-B with CCA-C indicate that PXTS-B is equally ...
J Goswami, A Abramson, R Buff, D D Nicholas, T Schultz
Influence of acidification on decay processes of CCB treated wood
2004 - IRG/WP 04-10514
The phenomenon of copper tolerance by brown rot fungal strains has been known for a long period but the complete mechanism of copper tolerance by these fungi is not understood yet. Copper tolerance has previously been linked to oxalic acid excreted by copper tolerant brown rot fungal strains. This acid reacts with copper in the wood to form an insoluble and therefore less toxic copper oxalate. The...
M Humar, S A Amartey, M Šentjurc, F Pohleven
Durability aspects of (hydro)thermal treated wood
2000 - IRG/WP 00-40160
Samples of several wood species were treated in a two steps process, subsequently hydrothermal and dry heat-treated, by the so-called PLATO-process and analysed for their resistance against fungal attack. Both PLATO-treated and dry heat-treated specimen were prepared and analysed, in order to study the influence of moisture during hydrothermal treatment of wood. The resistance against all of the s...
B F Tjeerdsma, M Stevens, H Militz