Your search resulted in 456 documents. Displaying 25 entries per page.
Fungal colonisation of the keelson and associated structures of a nineteenth century wooden frigate: Concepts of community structure and development
1994 - IRG/WP 94-10072
The early stages of microbial colonization and succession of wooden surfaces exposed to the sea have been extensively studied as have the community structures of archaeological timbers subjected to submergence and then retrieval from the sea. The frigate UNICORN, a largely intact 19th century wooden ship based in Dundee, Scotland, provides the microbial ecologist with a unique opportunity to study...
N A White, J W Palfreyman, G M Smith
Evaluating the resistance of wood-based panel products to fungal attack
1995 - IRG/WP 95-20071
At present there is considerable disagreement among national research institutes within Europe and panel product manufacturers on the most appropriate method of testing and indeed the need for specific biological durability testing. This paper seeks to place before a broader international audience, the issues related to development of a European standard for evaluating the resistance to fungal dec...
R G Lea, R W Berry
Mechanisms of Protection by NHA Against Fungal Decay
2002 - IRG/WP 02-10429
Treating wood with the water-borne sodium salt of N'-N-naphthaloylhydroxylamine (Na-NHA) protects wood against decay and termite damage. Initial testing indicated little or no inhibition of sapstain fungi, molds, or soft-rot fungi by Na-NHA, suggesting that the
mechanism by which this compound protected wood was complex and not that of a broad-spectrum biocide. Previously, we (Green et...
F Green III, W Henry, T Schultz
Screening of the efficacy of tall oils against wood decaying fungi
2004 - IRG/WP 04-30354
Tall oil is a by-product in pulping of resinous wood by the sulphate process. Tall oil contains a complex mixture of wood extractives. Some of these extractives act as natural protection against wood decaying fungi while other serve as nutrition for the fungi.
This report describes a screening of the efficacy of four refined tall oils with different chemical composition on wood decaying fungi. ...
G Alfredsen, P O Flæte, A Temiz, M Eikenes, H Militz
Alternative technologies for wood wastes recycling - Part A: Supercritical extraction of PAH compounds from wood wastes
1998 - IRG/WP 98-50101-18 a
Alternative technologies have been investigated to detoxify treated wood. Two classes of organic compounds are studied. Creosote-treated wood are classified in France as dangerous wood wastes. A conventional incineration could be provided for these wood wastes but the cost of this elimination could be very high (> 2000 FFR/ton). For these reasons, we have tested two kinds of new processes as al...
L Schrive, C Perre, G Labat
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
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
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
Study of the degradation caused by micro-organisms in Pinus sp. waterlogged wood
1989 - IRG/WP 1411
So far, the different Centers are trying the restoration and the conservation of wood structures, coming from subaquatic archeological deposits, with interest from the historic - artistic point of view. The main objective of this paper has been the determination of the decay level of Pinus sp. wood coming from a roman ship (approximately 2000 years old), where we have analyzed their physical prope...
M T De Troya, M C Escorial, J Garcia, A Cabanas
Resistance of acetylated wood to biological degradation. Evaluation of field test
1997 - IRG/WP 97-30139
Acetylated wood samples were tested in ground contact (stake test) at two test fields, one in Simlångsdalen, Sweden, and one in Viikki, Finland, according to European standard EN 252. The test samples were inspected annually and their condition was compared with that of untreated controls and of samples treated with two reference CCA preservatives. The use of untreated controls and preservative t...
P Larsson Brelid, R Simonson, Ö Bergman
Some studies on fungal deterioration of rubber wood (Hevea brasiliensis)
1980 - IRG/WP 2140
For the sreening of anti-stain chemicals trials with selected agricultural fungicides and new chemicals were carried out. Botryodiplodia theobromae, Aspergillus sp. and Penicillium sp. were used at test organisms. For testing the durability of rubber wood (Hevea brasiliensis) suitable local rotting fungi (Basidiomycetes), based on high degrading power, which may later be employed in standard tests...
A Sujan, A G Tan, M Stevens
Cytoplasmic and extracellular localization of manganese II dependent peroxidase(s) in white rot fungi during degradation of woody materials
1989 - IRG/WP 1416
The manner by which lignin is degraded in-situ in natural substrates by white rot fungi still remains a controversial issue particularly the distribution and role(s) played by lignin degrading enzymes (i.e. manganese II peroxidase and lignin peroxidase). In the present study, use was made of anti-manganese II peroxidase and immunolabelling techniques in conjunction with transmission electron micro...
G F Daniel, B Pettersson, T Nilsson, J Volc
Differences in pH, electrical resistance, cation composition and NIR spectra of red spruce wood during early stages of brown rot degradation
2002 - IRG/WP 02-10449
Red spruce sapwood was exposed to degradation by the brown rot fungi Coniophora puteana, Postia placenta, Gloeophyllum trabeum and Serpula lacrymans for 0, 1, 2 or 3 weeks using a modified soil block assay design. Average weight losses over time ranged from 0-8.9% during this time period. Detectable changes in pH, electrical resistance and cation compostion were observed in the wood as early as 1 ...
J Jellison, S Kelley, B Goodell, D Hui, A Ostrofsky
Fungal siderophores and their rôle in wood biodegradation
1990 - IRG/WP 1442
Iron and other metals such as manganese, play an important role in the metabolic functions of fungi that cause wood deterioration. These transition metals are also found in, or associated with, the extracellular fungal enzymes shown to be directly involved in the decay process. Recently our research group was able to show that siderophores (low molecular weight biological chelators) are produced b...
J Jellison, B Goodell, F Fekete, V Chandhoke
Microbial decay in an extremely durable Malaysian hardwood Belian (Eusideroxylon zwageri) - an overview
1997 - IRG/WP 97-10216
The heartwood of Belian (Eusideroxylon zwageri) is highly regarded among the naturally durable Malaysian hardwoods, and is therefore a choice timber for soilcontact use in the humid tropics such as untreated telecommunication poles, fence posts and railway sleepers. The high microbial resistance of the wood is evidenced by the mere superficial degradation observed in some pole samples after 20 yea...
A H H Wong, A P Singh
Sapstain development on Jack pine logs in Eastern Canada
2000 - IRG/WP 00-10358
During 1998-99, a study was initiated to investigate the influence of seasons, log types and storage time on the sapstain development on jack pine logs at two sites in Eastern Canada. Jack pine trees (Pinus banksiana) were harvested into whole-tree and cut-to-length logs in spring and in autumn. Sapstain development was examined in these logs at 2 to 4 week intervals after felling. The mean stain ...
Dian-Qing Yang, R Beauregard
Regulation of hyphal sheath formation iron-chelator production by the brown rot fungi Gloeophyllum trabeum and Postia placenta
1994 - IRG/WP 94-10074
Hyphal sheath formation and iron-chelator production by liquid cultures of the brown rot fungi Gloeophyllum trabeum and Postia placenta were monitored over time. The effects of incubation at various temperatures, pH's and concentrations of iron, manganese and nitrogen were determined. Hyphal sheath production was observed microscopically and quantified with JAVA video analysis. The hyphal...
Y Chen, J Jellison
Assessing the importance of degradation mechanisms on the loss of effectiveness of wood preservatives
2000 - IRG/WP 00-20193
Accelerated ageing systems developed for application to samples in the laboratory prior to biological tests, should reflect those natural deterioration processes that are likely to occur in the hazard classes defined in EN 335-1. Losses through evaporation or the effects of leaching have been recognised, however their importance, relative to other mechanisms has not been quantified. Degradation me...
E D Suttie, R J Orsler, T Dearling
Bacterial degradation of Pinus radiata compression wood
1996 - IRG/WP 96-10153
An inspection of twelve year old, CCA-treated Pinus radiata wood from an industrial cooling tower showed extensive surface decay of wood. Electron microscopic examination of decaying compression wood indicated that compression wood cells were attacked exclusively by bacteria, which were of erosion and tunnelling types. As compared to the normal wood, compression wood appeared to be more resistance...
A P Singh, R N Wakeling
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
The influence of drying and chemical stress on the lignin degradation in aspen by Phanerochaete chrysosporium
1992 - IRG/WP 92-1573
Wood wafers of Populus tremuloides sapwood were incubated on common media with the white rot fungus Phanaerochaete chrysosporium (wild isolate) and subjected to cyclic drying or chemical agents (low levels of borate or trifluoperazine [a calmodulin antagonist]). After a mass loss of approximately 5.5%, wafers were dried and analyzed for acid-insoluble lignin. Those wafers containing chemical agent...
E L Schmidt, Y-L Lin
Breakdown of cellulose derivatives by cellulolytic enzymes. I. Action of fungal ß-glucosidases toward substituted PNP ß-D-glucopyranosides
1998 - IRG/WP 98-10281
The action of fungal ß-glucosidases on the methyl derivatives of p-nitrophenyl (PNP) ß-D-glucopyranoside, which were regioselectively substituted at 0-2, 0-3, 0-4 and 0-6 positions was studied. Several ß-glucosidases from brown-rot, white-rot, and soft-rot fungi and almond were used for the study. These ß-glucosidases did not act on the 2, 3, and 4-0-methyl derivatives, while the 6-0-methyl on...
T Nishimura, I Momohara, M Ishihara
Improved preservative penetration of spruce after pre-treatment with selected fungi. I. Fungal pre-treatment of pole sections
1998 - IRG/WP 98-40117
European spruce logs were pre-treated with either Phanaerochete chrysosporium, Dichomitus squalens, Trichoderma viride and Trichoderma aureoviride for incubation periods of between 1-4 weeks prior to pressure treatment with creosote in a commercial treatment plant and analysed for strength and creosote uptake (see part II Tucker et al.). A method to pre-treat logs was optimised. The pole sections ...
B Rosner, K Messner, E J B Tucker, A Bruce
The suitability of isothiazolone microemulsions as long term wood preservatives
1997 - IRG/WP 97-30150
Microemulsion formulations of 4,5 dichloro-2-n-octyl-4-isothiazolin-3-one were investigated to determine the leaching potential of these formulation types as well as their efficacy against decay fungi. These patented low leaching formulations exhibited good anti fungal efficacy in standard tests combined with minimal leaching of the active ingredient from the wood. The data suggests that the excel...
B M Hegarty, Bing Yu, L E Leightley