Your search resulted in 1091 documents. Displaying 25 entries per page.
The production of extracellular hydrogen peroxide by some brown-rot fungi
1990 - IRG/WP 1446
The role of hydrogen peroxide (H2O2) has been discussed in the degradation of wood by wood-rotting fungi. The production of extracellular hydrogen peroxide was studied by detecting the oxidation of the chromogen 2,2'-azinobis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) by H2O2 and horse radish peroxidase (HPR). ABTS and HPR were added to a solid wood based culture media. In this study ...
A-C Ritschkoff, L Paajanen, L Viikari
Immunolocalization of extracellular metabolites from Poria placenta
1988 - IRG/WP 1361
Polyclonal antisera produced to Poria placenta extracellular metabolites was used in immuno-fluoresence microscopy and immuno-gold TEM studies. In the fluorescence work, labelling of Poria placenta hyphae in wet fixed wood material was observed but not in infected wood which was oven dried prior to sectioning and immunolabelling. TEM studies provided better resolution, with gold labelling detected...
B Goodell, G F Daniel, J Jellison, T Nilsson
Fungitoxic effect of the quaternary ammonium compounds wood preservatives against the Ascomycetes and Deuteromycetes
1997 - IRG/WP 97-30138
Results of investigation on fungitoxic value of the three formulations of wood preservatives based on the quaternary ammonium compounds (lauryldimethylbenzylammonium chloride, lauryldimethylbenzylammonium bromide, alkylbenzyldimethylammonium chloride) in relation to the surface wood colouring (moulds) and soft-rot fungi have been presented. The agar-plate (screening) and agar-wood plate for mouldi...
J Wazny, P Rudniewski
Cation analysis of wood degraded by white and brown rot fungi
1992 - IRG/WP 92-1552
Changes in the concentrations and composition of cations within wood colonized by the brown-rot fungi Postia placenta and Gloeophyllum trabeum and the white-rot fungi Trametes versicolor and Phanaerochaete chrysosporium were analyzed using plasma emission and atomic absorption spectrophotometry. In degraded poplar wood significant decreases in pH and electrical resistance readings were observed as...
J Jellison, K C Smith, W T Shortle
Resistance of acrylic paints on wood against growth of the rot fungus Dacrymyces stillatus
1990 - IRG/WP 2345
In the last few years the presence of the rot fungus Dacrymyces stillatus has been repeatedly confirmed in external wood panels, particularly from wood painted with water based paints. A laboratory method for testing of the fungal resistance of paint films on wood has been developed.This method has been used to test the efficacy of the fungicides Parmetol DF 18 and Parmetol HF 25 against attack by...
J Bjurman
Method of embedding and staining of wood after biological testing to support the identification of decay type
1998 - IRG/WP 98-20131
A method for preparing wood for microscopic analysis after decay testing is described, with special regard to a novel fast simultaneous staining, which helps to identify different types of decay. The novel staining process is explained as well as the embedding of heavily decayed samples in polyethylene glycol (PEG) and picking up of sections by transparent adhesive tape. Special feature of the int...
A O Rapp
Occurrence and importance of various types of fungal and bacterial decay in CCA-treated horticultural pine posts in New Zealand
1984 - IRG/WP 1234
A detailed microscopical examination has been carried out on samples taken from CCA-treated pine posts exposed in horticultural soils. The following decay types were observed: white rot, brown rot, soft rot, tunnelling bacteria, cavitation bacteria, and bacterial erosion. The occurrence and importance of the various decay types between different regions, and plots within a specific region, varied ...
T Nilsson
Extracellular osmiophilic particles in connection with brown rot and white rot
1982 - IRG/WP 1157
The way of attack on Pine woodblocks of two brown-rot fungi (Fomitopsis pinicola, Coniophora puteana) differing in their cellulase activities, and one white-rot fungus (Trametes hirsuta) has been investigated by transmission electron microscopy. Even at early stages of decay, osmiophilic particles were found with all the fungi investigated. In the brown-rotted wood, the osmiophilic particles occur...
K Messner, H Stachelberger
Production, function and neutralization of oxalic acid produced by the dry rot fungus and other brown rot fungi
1987 - IRG/WP 1330
The formation of oxalic acid by the wood-destroying fungi causing brown rot, is found to be the key which by hydrolysing the hemicellulose brings the cellulose in the tracheid wall in contact with the cellulase enzymes and yeld watersoluble sugars leaving only a lignin skeleton. To control the pH in the substrate the excess oxalic acid is precipitated to water insoluble calcium oxalate by the dry ...
J Bech-Andersen
The role of oxygen and oxygen radicals in one-electron oxidation reactions mediated by low-molecular weight chelators isolated from Gloeophyllum trabeum.markup
1994 - IRG/WP 94-10086
The KTBA assay for determination of one-electron oxidation activity was used to assay reactions of low-molecular weight chelators isolated from the brown rot fungus Gloeophyllum trabeum. The assay, performed either under air or nitrogen showed that molecular oxygen was an important factor in chelator-mediated oxidation reactions. A reduction in oxidative activity was observed when superoxide dismu...
Jun Lu, B Goodell, Jiang Liu, A Enoki, J Jellison, H Tanaka, F Fekete
Hydrolysis of bordered pits during colonization of conifers by brown-rot fungi
1995 - IRG/WP 95-10103
Brown-rot decay results in rapid reduction in degree of polymerization (DP) of holocellulose with concomitant strength loss (MOR) without removing lignin. Development of new methods of wood protection will require focusing on early events in the sequence of depolymerization. Bordered pit membranes (sapwood) represent a readily available source of non-lignified carbohydrate, ie. pectin and cellulos...
F Green III, J L Tschernitz, T A Kuster, T L Highley
Antagonistic properties of Gliocladium virens against wood attacking fungi
1996 - IRG/WP 96-10162
Gliocladium virens has shown good antagonism against decay fungi in agar medium and in wood blocks. Gliotoxin produced by Gliocladium virens is associated with biocontrol of some plant diseases, but its importance to biocontrol of wood-attacking fungi is unknown. We investigated the ability of gliotoxin-producing (GLT+) isolates of Gliocladium virens and gliotoxin-deficient (GLT-) mutants of Glioc...
T L Highley, H S Ananthapadmanabha, C R Howell
Micromorphology of oak wood degraded by brown rot fungus Coniophora puteana
2000 - IRG/WP 00-10356
To characterize the degradation of hardwood by brown rot fungus, Coniophora puteana was incubated on the wood blocks of Quercus accutissima. For comparison, the same fungus was also incubated on the pine wood blocks of Pinus densiflora. In softwood, the shape of the wood cells and thickness of the cell appeared unchanged even the loss of birefringence in the affected areas. In contrast, oak wood d...
Yoon Soo Kim, Seung-Gon Wi, Kwang-Ho Lee
The importance of blue stain attack for the colonization by wood-rotting fungi of wood not in contact with the ground
1988 - IRG/WP 1349
When used in constructions not in contact with the ground, wood has been shown often to proceed from blue stain to moulds. The appearance of wood rotting fungi is normally delayed. Solid wood artificially inoculated with the blue stain fungus Pullularia pullulans was shown to permit germination of Pycnoporus cinnabarinus basidiospores. This was demonstrated by the use of an indirect and a direct b...
J Bjurman
Oxalic acid metabolism of Postia placenta
1992 - IRG/WP 92-1566
The oxalic acid metabolism of Postia placenta was studied in liquid culture in order to identify the metabolic pathways of biosynthesis and to determine whether oxalic acid physiology could be correlated with efficiency in wood decay. Oxalic acid production was determined for test strain MAD698 grown in a basal defined medium with a variety of different carbohydrate and nitrogen sources. The highe...
J A Micales
Immuno-scanning electron microscopic localization of extracellular polysaccharidases within the fibrillar sheath of the brown rot fungus Postia placenta
1991 - IRG/WP 1497
Extracellular polysaccharidases of the brown-rot fungus Postia placenta were localized using colloidal gold labeled monoclonal antibodies to the B-1,4-xylanase (32-36kDa) fraction of Postia placenta. Postia placenta was grown from agar onto glass coverslips, immunolabeled with or without prior fixation, and examined by SEM. Enzymes were localized on the hyphal surface and on the clumped fibrillar ...
F Green III, C A Clausen, M J Larsen, T L Highley
The effect of Tween 80 on the growth, morphology, and enzyme secretion of Postia placenta
1990 - IRG/WP 1456
The nonionic surfactant Tween 80 (polyethylene oxide sorbitan mono-oleate) has been reported to increase enzyme production and/or secretion in bacteria and fungi. Such a procedure could greatly facilitate research into the physiology of wood-decay fungi since quantities of available enzyme are often limiting. The brown-rot fungus Postia placenta was grown in a synthetic medium supplemented with 0,...
J A Micales
Changes in some important mechanical and physical properties of untreated and treated mining timber after exposure to the conditions of a colliery
1996 - IRG/WP 96-20082
Each of salt treated and untreated mining timber (wedge) pairs with 5x15 cm² cross-section and 155 cm length prepared from Scots pine, Bornmüller's fir and oriental beech was cut in the small standard test specimens to determine changes in some important mechanical and physical properties, 13 month after exposure to the conditions of Kozlu Hard Coal Mines in the depth of 52 m. Thus, the...
A Bobat
Preliminary investigation on the natural durability of Guayule (Parthenium argentatum)-based wood products
2000 - IRG/WP 00-40154
Conventional preservatives used to protect wood from insect and microbial damages are presently of major concern to human health and the environment. Finding alternative and economical preservatives has not been successful. Previous studies have shown that the resinous material extracted from the guayule plant (Parthenium argentatum, Gray) has both insect- and microbial-resistant properties. Unfor...
F S Nakayama, P Chow, D S Bajwa, J A Youngquist, J H Muehl, A M Krzysik
Effect of remediation on the release of copper, chromium, and arsenic from particleboard made from CCA treated wood
2001 - IRG/WP 01-50170
This study sought to determine the effect of remediation with oxalic acid (OA) extraction and Bacillus licheniformis fermentation on the release of copper, chromium, and arsenic from particleboard made from remediated wood particles and also investigates durability of the particleboard against white and brown- rot fungi. Particleboard samples were manufactured using untreated, CCA-treated, OA-extr...
S N Kartal, C A Clausen
Defining fungal decay types - A proposal for discussion
1985 - IRG/WP 1264
The present definitions of the fungal decay types, white rot, brown rot, and soft rot are somewhat vague. The definitions are based on a mixture of criteria involving morphological and chemical aspects of decay as well as taxonomic affiliation of the responsible fungal species. The present vague definitions have led some fungi being erroneously places in a wrong decay type. Furthermore, some fungi...
T Nilsson
Neem leaves, a potential source for protection of hardwood against wood decaying fungus
2005 - IRG/WP 05-30370
Neem leaves are widely recognized for their insecticidal, pesticidal, fungistatic and fungitoxic ability. The present study is to investigate the efficacy of neem leaves extractives against wood destroying microbes, a brown and a white rot. Neem leaves extractives prepared in various solvents such as petroleum ether, acetone, ethanol, methanol and hot water were tested at a concentration levels of...
S Dhyani, S Tripathi, V K Jain
The action of siderophores isolated from Gloeophyllum trabeum on the structure and crystallinity of cellulose compounds
1991 - IRG/WP 1479
Low molecular weight, high affinity iron-binding compounds (siderophores) were isolated from the brown-rot fungus Gloeophyllum trabeum. The compounds were shown to be inducible by iron starvation and could be purified by ultra-filtration, ethyl acetate extraction, column chromatography and preparative HPLC. The isolated compounds were shown by analytical and immunological techniques to be produced...
J Jellison, V Chandhoke, B Goodell, F Fekete, N Hayashi, M Ishihara, K Yamamoto
A model for attack at a distance from the hyphae based on studies with the brown rot Coniophora puteana
1995 - IRG/WP 95-10104
In timber infested by brown rot fungi, a rapid loss in strength is attributed to production of hydroxyl radicals (HO·) at a distance from the hyphae. The immediate precursor is Fenton's reagent (Fe(II)/H2O2), but the pathways leading to Fe(II) and H2O2 have remained unclear. Cellobiose dehydrogenase, purified from cultures of Coniophora puteana, will couple oxidation of cellodextrins to ...
S M Hyde, P M Wood
Influence of the content of organic matter of soil on the degradation of wood by soft rot fungi
1970 - IRG/WP 27
The degradation of wood specimen burried in the soil by soft rot fungi is influenced by a number of factors. These are in particular the water holding capacity, water content, content of organic matter, pH, content of mineral nutritive substances etc. The results of the interlaboratory tests, carried out within the IRG/WP let presume that the intensity of wood degradation occurs proportionally inv...
O Wälchli