Your search resulted in 760 documents. Displaying 25 entries per page.
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
Accelerated laboratory testing of preservatives on 13 North American wood species
1999 - IRG/WP 99-30201
The ability of selected water and solvent based biocides to protect wood against fungal attack was evaluated on 13 North American wood species using 7 decay fungi in a modified soil block test. Most preservatives were capable of providing protection at their recommended above ground and soil contact use levels. Many decay fungi caused substantial weight losses on blocks treated with chlorothalonil...
J J Morrell, C M Freitag
Fenton's reagent as a modification tool in brown-rot decay
1996 - IRG/WP 96-10155
A biomimetic approach was used to clarify the role and importance of the Fenton-type reaction in the carbohydrate degradation by brown-rot fungi. Spruce sawdust and microcrystalline cellulose were modified in the H2O2/Fe(II) treatment. The degree of hydrolysis of the pretreated spruce sawdust was clearly increased with the complete cellulase (Econase), purified endoglucanase from Trichoderma reese...
M Rättö, A-C Ritschkoff, J Buchert, L Viikari
Immunolocalization of xylanase produced by Clostridium xylanolyticum Rogers and Baecker during anaerobic decay of Pinus patula
1991 - IRG/WP 1505
The xylanolytic fraction from a 72h culture of Clostridium xylanolyticum ROGERS and BAECKER was separated using non-denaturing PAGE and then used to raise polyvalent antisera in rabbits. Antibodies were purified using an affinity gel column and coniugated with colloidal gold. Pinus patula was exposed to axenic cultures of Clostridium xylanolyticum for 3 weeks, fixed, embedded and converted to ultr...
A A W Baecker, G M Rogers
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...
H Viitanen
Biochemical relationships between biodegradation of cellulose and formation of oxalic acid in brown-rot wood decay
1991 - IRG/WP 1472
Non-enzymic hydrolysis of cellulose with low concentrations of oxalic acid was examined. The incubation of pine wood pulp with 1% oxalic acid (pH 1.3) at 35°C for 4 weeks reduced the original viscosity to 60%. Reducing sugars were liberated from various cellulosic samples by the oxalic acid treatment. However, crystallinities of cellulose in those samples did not change before and after the treat...
M Shimada, Y Akamatsu, A Ohta, M Takahashi
Accelerated decay tests on DNBP-treated Pinus patula and Eucalyptus grandis
1987 - IRG/WP 3441
Blocks (10 x 10 x 5 mm³) of Pinus patula and Eucalyptus grandis were impregnated to 0, 1.5, 3.0 and 4.5 kg/m³ 2-sec-butyl, 4, 6 dinitrophenol (DNBP). They were monitored microscopically and for weight losses over 16 weeks against monocultures of Coriolus versicolor and Coniophora puteana. Treated ministakes (10 x 10 x 100 mm³) and blocks in soil contact were similarly monitored to determine wei...
L D Abraham, A A W Baecker
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
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
Isolation of soil borne bacteria and fungi from treated timber
2001 - IRG/WP 01-50174
Most research in the last few decades has focused on the development of new strategies to control biological attack and the means to quantify this. Comparatively little work has been done to examine the effect that treated timber might have on its surrounding environment. This presentation will describe a methodology that attempts to detect any changes which might occur in the soil microflora foll...
I Stephan, A Stegemann, G Heidrich
Evidence for the participation of the osmiophilic particles in the enzymatic demethylation of lignin
1984 - IRG/WP 1239
Transmission electron microscopic observations of the white-rot fungi Trametes hirsuta and Phanerochaete chrysosporium grown on a series of wood pulp with a graded lignin content and mycelium from the clarified centre of an agar-medium containing lignin (E1-effluent from the bleaching process) showed that osmiophilic particles are only induced by native lignin. Taking into account that the osmioph...
K Messner, H Stachelberger
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
Degradation of lignin model compounds with coordinated copper in the presence of peroxide
1998 - IRG/WP 98-10282
A novel diffusible system capable of decomposing lignin model compounds with copper, coordinators and peroxides has been proposed. When pyridine was used as a copper coordinator, two synthetic dyes, Poly-R and RBBR were intensively decolorized with Cu(II) and H2O2 in aqueous solutions at room temperature. Although reactions with Cu(II) and H2O2 produce a strong oxidant, hydroxyl radical, via a Fen...
K Koller, K Messner, T Watanabe
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
Studies on the resistance of DMDHEU treated wood against white-rot and brown-rot fungi
2005 - IRG/WP 05-10566
Beech wood (Fagus sylvatica) modified with the textile finishing agent 1,3 dimethylol-4,5-dihydroxyethylen urea (DMDHEU) has shown to improve durability against the white-rot fungus Trametes versicolor. In a mini-block test, the weight loss over eight weeks of incubation decreased with increasing weight percent gain (WPG) of DMDHEU. At 25% WPG, no significant weight loss was observed, while untrea...
P Verma, C Mai, A Krause, H Militz
Bacterial brown stain on sawn timber cut from water-stored logs
1992 - IRG/WP 92-1532
Brown stains which appear on the surface of sawn radiata pine cut from water-stored logs were identified as tannin-like compounds. They are derived from bacterial breakdown of flavanoid-glucosides. When timber is sawn from infected logs, the free flavanoids migrate to the wood surface as the timber dries. There, they condense and oxidise to form permanent brown discolourations. Stains occurred on ...
M E Hedley, R Meder
Distribution of copper/chrome/boron preservative in light red meranti (Shorea leprosula) before and after exposure test for 72 months
1995 - IRG/WP 95-20073
Copper/chrome/boron (CCB) preservative at 6% w/w was impregnated into light red meranti (Shorea leprosula) by full cell process. The quantitative analysis for copper, chrome and boron contents in treated wood samples was carried out by Inductive Couple Plasma (ICP). Electron Probe Microanalyser (EPMA) was used to monitor the distribution of copper, chrome and boron in the various treated wood tiss...
S Salamah, S Ani
Evaluation of bacteria for biological control of wood decay
1990 - IRG/WP 1426
Laboratory soil-block and agar-block tests were carried out to evaluate the efficacy of bacteria as biological control agents against 5 brown-rot and 3 white-rot fungi. Pretreatment of Southern pine and sweetgum with a bacterial solution prevented decay in agar-block tests. However, the bacteria were generally ineffective in preventing decay in Southern pine, Douglas-fir, sweetgum and yellow popla...
R Benko, T L Highley
Degradation features of waterlogged archaeological compression wood
1998 - IRG/WP 98-10258
The degradation characteristics of waterlogged archaeological compression wood excavated in South Korea were examined by transmission electron microscopy (TEM) and confocal laser scanning microscopy (CLSM). Degradation of Pinus compression wood occurred mainly in the inner part of S2 layer. In contrast, the outer part of S2 layer remained relatively intact. CLSM and TEM showed the erosion type of ...
Yoon Soo Kim, A P Singh
Molecular studies on house rot fungi by RAPD-PCR
1997 - IRG/WP 97-10195
For genetic information and in view as a possible diagnosis method various isolates of the dry rot fungus, Serpula lacrymans, the wild merulius, S. himantioides, and the cellar fungus, Coniophora puteana, from Asia, Europe and USA were investigated by the polymerase chain reaction (PCR) based technique of randomly amplified polymorphic DNA (RAPD). The banding patterns obtained revealed for S. lacr...
O Schmidt, U Moreth
Effect of volatiles from bacteria and yeast on the growth and pigmentation of sap-stain fungi
2000 - IRG/WP 00-10331
Sapstain fungi cause deterioration of wood due to colonisation by pigmented hyphae but without producing significant strength losses. This is due to the production of melanin in the fungal cell walls of the staining fungi. Any biological control strategy targeted against this type of deterioration would therefore be considered successful if it inhibited either fungal growth or pigment production. ...
A Bruce, R E Wheatley, S Verrall
Ponding of radiata pine (Pinus radiata) - 1. The effect of bacteria on wood
1998 - IRG/WP 98-10265
Radiata pine (Pinus radiata) wood panels which had been ponded for periods ranging from 2 to 12 weeks were examined by light microscopy, confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) for bacterial colonisation of wood and degradation of pit membranes. After 2 weeks of ponding bacteria colonised the outer few cells of wood, ...
A P Singh, Y S Kim, U Schmitt, B S Dawson