Your search resulted in 47 documents. Displaying 25 entries per page.
Antifungal activity of different molecular weights of a biopolymer chitosan against wood decay fungi
2008 - IRG/WP 08-30456
In recent years chitosan has been investigated as a natural polymer for wood preservation against fungal decay. From an environmental point of view, chitosan seems to possess a potential approaches as wood protecting agent. In this study, three different molecular weights of chitosan compounds (with approximately the same degree of deacetylation 83 ± 2 %) were evaluated as in vitro and in vivo as...
A S O Mohareb, M E I Badawy
Molecular Methods: a Reliable Tool for the Identification of Wood Decay Fungi in Construction Timber
2008 - IRG/WP 08-20386
In the present study, we tested the practical value of several DNA-based methods to identify at the species level the most common wood-decaying fungi infecting buildings. We successfully extracted and amplified fungal DNA from pure cultures of twelve species of wood-inhabiting fungi, from oak and pine wood infected in laboratory with known strains, and from unknown field samples of wood collected ...
M Maître, M Kutnik, I Le Bayon, L Harvengt
Wood Decay Research Using Molecular Procedures, What Can It Tell Us?
2008 - IRG/WP 08-10678
There are many unanswered questions in wood decay and protection research, and no single research technique will ever answer all of these questions. The process of wood decay is a very complex series of biochemical and chemical reactions that are heavily influenced by the hundreds of bacterial and fungal species found on environmental samples of wood. There are a variety of molecular techniques b...
S V Diehl, M. L Prewitt, Young-Min Kang, L Mangum, J D Tang
Degradation of wood veneers by Fenton’s reagents: effects of low molecular weight phenolic compounds on hydrogen peroxide decay and tensile strength loss
2009 - IRG/WP 09-20400
Pine wood (Pinus sylvestris) veneers strips were incubated in acetate buffer containing hydrogen peroxide and iron to mimic mechanisms of brown rot decay and assess the degradation of cellulose through analysis of the tensile properties of the decayed wood. The tensile properties of thin wood strips treated with Fenton system reagents or precursors were determined and correlated to weight loss as ...
Yanjun Xie, R Well, Zefang Xiao, B Goodell, J Jellison, H Militz, C Mai
Fungal Attack on Lignin and Cellulose: Elucidation of Brown- and White-Rot Mechanisms Comparing Biomimetic and In-Vivo Degradation Patterns
2010 - IRG/WP 10-10714
This paper examines research and hypotheses that have been developed over several years on wood degradation mechanisms. This information is combined with new data and analyses to explain why wood decay patterns caused by brown-rot fungi and specific types of white-rot fungi are different. New data, including work with both biomimetic studies on low molecular weight compounds, degradative enzymes, ...
V Arantes, B Goodell, A M F Milagres, Yuhui Qian, T Filley, J Jellison, S Kelley
Termite taxonomy and distribution with particular reference to climate change in Africa
2010 - IRG/WP 10-10738
Termites constitute an integral component of various ecosystems in Africa. Termites are also amongst the most difficult of the insects to study because of their cryptic behaviour. There are around 2600 species of termites (Isoptera) in 280 genera which have been described worldwide and about 39% of the total termite species are found in Africa. Some termite species are well known pests of agricul...
P O Y Nkunika, B M Ahmed Shiday, G W Sileshi, J R J French, P Nyeko, S Jain
Profiling fungal community in wood decay ecosystem by Denaturing High-Performance Liquid Chromatography
2010 - IRG/WP 10-20443
A DNA-based fingerprinting technique, Denaturing High Performance Liquid Chromatography (DHPLC) was developed to profile fungal communities colonizing indoor timber. Molecular fungal diversity was assessed using amplification based on the Internal Transcribed Spacer (ITS1) rDNA of 74 wood samples collected from infected buildings in France. Due to its high sensitivity, the PCR-DHPLC technique was ...
S Maurice, G Le Floch, M Le Bras-Quéré, J P Rioult, G Barbier
Photostabilization of Wood with Higher Molecular Weight UV Absorbers
2010 - IRG/WP 10-30524
Higher molecular weight UV absorbers were created by reacting the epoxy-functionalized UV absorber 2-hydroxy-4(2,3-epoxypropoxy)-benzophenone (HEPBP) with maleic, phthalic or succinic anhydride. The ability of the UV absorbers to photostabilize wood was then examined. FTIR-spectroscopy confirmed that HEPBP reacted with phthalic anhydride to create a polyester that preserved the UV-absorbing benzop...
P D Evans, M J Chowdhury
Molecular investigation of Postia placenta growing in modified wood
2011 - IRG/WP 11-10756
Brown rot is the most common and destructive type of fungal decay for wood in service. These fungi depolymerize preferentially the structural carbohydrates, cellulose and hemicellulose in the cell wall leaving oxidized lignin behind. Modified wood can provide protection against a variety of wood deteriorating organisms, including decay fungi. However, there is still little known about the mode of ...
B Schmöllerl, G Alfredsen, C G Fossdal, M Westin, A Steitz
Design, synthesis, characterisation and effectiveness of ‘Locked-in-Boron’ chemicals for H3.2 level of wood protection
2011 - IRG/WP 11-30577
Boratrane molecules with five-membered and six-membered molecular ring systems, and with various ring substituents were synthesised, characterised and formulated for wood treatment for accelerated laboratory bioassays using wood decay fungi as test organisms. Six-membered ring boratranes showed lower efficacy in laboratory assays than five-membered ring boratranes. One alkyl-substituted boratran...
R Franich, H Kroese, S Gallagher, S Hill, B Kelly, G Billett, R Meder, W Rae
Smart hydrogels from low molecular weight amphiphilic compounds: toward a solution to decrease leachability and increase efficacy of boron preservatives?
2012 - IRG/WP 12-30589
A new catanionic system associating amphiphilic carnosine (AlaHisC8) and lauric acid forms supramolecular hydrogel at very low concentration. This gel was investigated and we have checked the validity of the concept of hydrogels utilization to reduce boron leachability and to develop new wood protection treatments. Impregnation with 5% aqueous borax solution (w/w) and 0.3% gelator agent (...
F Obounou Akong, P Gérardin, C Gérardin-Charbonnier
Hydrogels: a solution to reduce boron leachability without reduction of its biodisponibility to wood decaying fungi?
2012 - IRG/WP 12-30602
Products used today for wood protection must fulfill to more and more environmental constraints, such as being of low toxicity in answer to the Biocidal Product Directory, but also to involve waterborne treatments to limit rejection of volatile organic compounds in the atmosphere. Boron preservatives have been described as valuable alternatives for wood protection for non-ground contact applicatio...
F Obounou Akong, P Gérardin, M-F Thévenon, S Parant, C Gérardin-Charbonnier
What molecular biology can tell us about the biodegradation of lignocellulose: the utilization of molecular techniques for the detection, identification and enhanced understanding of wood degrading organisms
2013 - IRG/WP 13-20528
Molecular techniques are now routinely used in the identification, detection and analysis of wood degrading organisms. An overview of some of the early work on nucleic acid isolation and characterization will be followed by a discussion of the power of sequencing and other procedures for better understanding: the mechanisms involved in the biological degradation of wood, the metabolic basis of pre...
J Jellison, B Goodell, G Alfredsen, D Eastwood, G Daniel, S M Cragg, J K Grace
State of progress of utilisation of supramolecular gels for formulations of water-soluble wood preservation salts
2013 - IRG/WP 13-30630
This article is a compilation of the work done so far concerning the utilization of supramolecular hydrogels, built on low-molecular-weight amphiphilic molecules and containing boron salts conferring fungicidal properties. Mixing boron with thermoreversible hydrogels allows the formation of a supra molecular network incorporating boron and important amount of water upon gelification of the solutio...
F Obounou Akong, P Gérardin, M-F Thévenon, C Gérardin-Charbonnier
Molecular characterization and biodiversity of wood-decaying fungi in French Guiana
2014 - IRG/WP 14-10825
Fungi from tropical regions are currently under-represented in the classification system. Indeed, difficult access to tropical forests and irregular occurrence carpophores make it complicated to study fungus species in such environments, unlike in European zones where fungal diversity and taxonomy are better known. The purpose of this work was to enhance classification by integrating new data that...
A Zaremski, L Gastonguay, C Zaremski, J Beauchene
Wood biodeterioration monitoring using molecular fluorescence
2016 - IRG/WP 16-20589
Wood is an extremely complex and heterogeneous biological material, susceptible to biodeterioration by wood-destroying organisms. This process can be evaluated by natural resistance tests or non-destructive techniques, such as molecular fluorescence. The fluorescence of wood can be attributed to the presence of fluorophores groups or extractives, as a characteristic of some species. This study aim...
E Meneses Oliveira, A Florian da Costa, J W Batista Brag
NGS analysis of fungal OTUs in Aquilaria sp. from French Guyana, Cambodia, Laos and Thailand
2017 - IRG/WP 17-50328
Aquilaria is a tree species belonging to the Thymeleaceae family. When Aquilaria sp. is injured, it produce agarwood. Agarwood is characterized by a darker wood colour than the healthy one and by a strong perfume that is much esteemed by perfumers and some oriental religious communities. The production of agarwood is presumed to depend of environmental factors, among them fungi. The aim of this wo...
C Zaremski, C Malandain, O Sibourg, C Andary, G Michaloud, M Ducousso, N Amusant, A Zaremski
Molecular identification of marine borers causing wood deterioration on marine facilities in Korea
2019 - IRG/WP 19-10955
The deterioration factors of wood which was used in the marine environment, Tongyeong (South Coast) and Incheon (West Coast) in Korea, were investigated in order to develop technologies for safe and long-term use of timber in ocean facilities.
The marine microorganisms isolated by damaged wood were identified as morphological Chelura sp. and Teredo sp. As a result of DNA sequencing, it was confir...
Sae-Min Yoon, Min-Ji Kim, Won-Joung Hwang, Yong-Seok Choi, Dong-Won Son
Limiting Polysaccharide Motion Protects Wood From Decay
2020 - IRG/WP 20-40890
It is well known that chemical modifications to improve decay resistance also reduce the equilibrium moisture content (EMC) of wood. The mechanism of this action, however, has been the subject of much debate. Several groups have suggested that decay resistance is a result of lower diffusion rates of fungal degradation agents through the wood cell wall. A recent paper explained the fundamental prin...
C G Hunt, S L Zelinka, J E Jakes
Application of suberin fatty acids extracted from birch bark for wood coating
2021 - IRG/WP 21-40914
It is well known that chemical modifications to improve decay resistance also reduce the equilibrium moisture content (EMC) of wood. The mechanism of this action, however, has been the subject of much debate. Several groups have suggested that decay resistance is a result of lower diffusion rates of fungal degradation agents through the wood cell wall. A recent paper explained the fundamental prin...
A Kumar, Risto Korpinen, Veikko Möttönen
Molecular dynamics investigation of wood modification with furfuryl alcohol
2022 - IRG/WP 22-40931
Molecular dynamics (MD) was applied to investigate and understand the structural characteristics and the interaction of cellulose and lignin with furfuryl alcohol for explaining the wood modification process. A single chain of cellulose polymer model and a softwood lignin model was considered to represent cellulose and lignin polymers. The obtained radial distribution function results revealed tha...
V Ponnuchamy, J Sandak, A Sandak
Resistance of phenol formaldehyde impregnated beech (Fagus sylvativa L.) LVL against biodegradation in soil contact
2023 - IRG/WP 23-40965
Alternatives to preservative impregnation are emphasized in Germany and other European countries. Even though these treatments significantly improve wood's resistance to decay, they often do not have a beneficial impact on the dimensional stability. One alternative product, which may be used in ground contact for items like poles and railway sleepers, could be beech (Fagus sylvatica L.) laminated ...
M Slabohm, C Brischke, S Bicke, H Militz