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Application of biotechnology in wood protection

https://library.fpinnovations.ca/en/permalink/fpipub5180
Author
Yang, D.-Q.
Date
March 2001
Edition
42038
Material Type
Research report
Field
Sustainable Construction
Author
Yang, D.-Q.
Date
March 2001
Edition
42038
Material Type
Research report
Physical Description
19 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Advanced Wood Materials
Subject
Wood
Series Number
E-3543
Location
Sainte-Foy, Québec
Language
English
Abstract
Canada is one of the largest exporters of forest products in the world. To develop and transfer low environmental technology to eliminate wood infection is one of Forintek's program goals, and biotechnology is one of such technology. The application of biotechnology in forestry and wood protection has been explored to a limited extent worldwide. In order to allow the Canadian wood industry to take advantage of this enabling technology, this report summarizes various activities conducted by Forintek to stimulate the development and application of biotechnology for wood protection in Canada. The report also intends to review previously published researches on the use of biotechnology in wood protection. It will discuss the potential benefits and challenges to the applications of biotechnology in this area. It will cover the needs and opportunities of linking biotechnology and wood pest control. The future trends of the research and development will be discussed. In the last section, recommendations will be made to Forintek for devising a vision of the application of biotechnology in wood protection. Wood is a renewable resource and plays an important role in the world economy; however, it is subject to attack from wood-degrading fungi and insects. In Canada, it is estimated that about 10 million m3 of softwood lumber is treated with anti-sapstain chemicals annually, and around 4% of the wood products are preservative treated against decay and termites. Biotechnology may help in developing more effective and low environmental impact technologies for wood pest control. In wood protection, biotechnology currently has applications in wood durability improvement, in genetic engineering for wood pest resistance, in biological protection of wood against insect, stain and decay damage, and in detection and diagnosis of wood sapstain and decay infection. The future application of biotechnology to wood protection is likely to focus on the development of diagnostic kits for wood degrading fungi, commercialization of bio-pesticides against fungal degradation, wood surface modification by enzymes, and genetic engineering of trees for durability. The key challenge faced by the Canadian biotechnology industry in the development and the use of biotechnology-derived products and processes of wood protection is the bio-product registration. Public attitude against the environmental release of genetically engineered organisms may also have a strong effect on the development of these bio-products. It is recommended that Forintek take the following roles in the future development of biotechnology in wood protection: a) to provide the knowledge base and the technology to contribute to enhanced tree breeding processed for wood durability; b) to develop safe and effective deployment strategies for sapstain and decay control biotechnology-derived products; c) to provide the knowledge base and the technology for more energy efficient and environmentally friendly wood protection processes; and d) to foster the acceptance of forest biotechnology by the Canadian wood products manufacturing industry.
Biological Control
Wood protection - Biotechnology
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Application of biotechnology to wood protection

https://library.fpinnovations.ca/en/permalink/fpipub5090
Author
Yang, D.-Q.
Date
March 2000
Edition
41940
Material Type
Research report
Field
Sustainable Construction
Author
Yang, D.-Q.
Date
March 2000
Edition
41940
Material Type
Research report
Physical Description
3 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Advanced Wood Materials
Subject
Wood
Series Number
General Revenue Progress Report
E-3408
Location
Sainte-Foy, Québec
Language
English
Abstract
Biological Control
Wood protection - Biotechnology
Bioprotectants
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Best practices guide to minimize mold growth on wood products from manufacture to end use

https://library.fpinnovations.ca/en/permalink/fpipub42463
Author
Uzunovic, Adnan
Byrne, Anthony (Tony)
Gignac, Manon
Yang, D.-Q.
Date
March 2011
Material Type
Guide
Research report
Field
Sustainable Construction
Author
Uzunovic, Adnan
Byrne, Anthony (Tony)
Gignac, Manon
Yang, D.-Q.
Contributor
Canadian Forest Service.
Date
March 2011
Material Type
Guide
Research report
Physical Description
32 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Advanced Wood Materials
Subject
Prevention
Growth
Series Number
Canadian Forest Service No. 38
W-2826
Location
Vancouver, British Columbia
Language
English
Abstract
This guide is intended to discuss mold-related issues and to assist the industry in the delivery of clean, mold-free products to the marketplace. Mold continues to be undesirable on wood products and can cause rejection of shipments by the customers and economic losses to the industry. This report provides an historic perspective on mold, defines mold and discusses why it became a major issue in the marketplace and how this relates to wood products. The main factors required for mold growth and expansion are discussed, as are methods of limiting mold growth. The best method of mold control is moisture control, which includes initial drying and keeping wood products dry. Specifically we give best practice guidelines for controlling mold on logs, lumber, plywood/veneers, other composite panel products, wood chips/residues, and for wood products in service (buildings). Lumber is one of the key products of the wood industry and several specific guidelines in regard to mold control for lumber are available and covered in depth. This includes air-drying, kiln-drying, phytosanitary heat treatment, and chemical prophylactic treatment of green lumber. Some circumstances where control of moisture is not feasible will require either chemical treatments or water barriers to prevent mold growth. There is also a special section on lumber packaging and wrapping, and water repellents. Finally, the report reviews existing guidelines for mold cleaning and remediation.
Mould growth
Moulds - Prevention
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Biological method to pre-dry lumber with wetwood

https://library.fpinnovations.ca/en/permalink/fpipub39015
Author
Yang, D.-Q.
Date
March 2007
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Yang, D.-Q.
Date
March 2007
Material Type
Research report
Physical Description
62 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Yeasts
Wetwoods
Seasoning
Bacteria
Series Number
General Revenue Project No. 4030
4030
Location
Québec, Québec
Language
English
Abstract
Wetwood, or water pocket, has higher moisture content (MC) and lower permeability than normal wood, which cause problems for lumber drying. The high moisture content of wetwood usually requires relatively long periods for adequate drying; consequently, it causes a high risk for developing checks, splits, crook, bow and twist of lumber in kiln drying. These problems have not been solved by any physical, chemical or mechanical methods yet. Using biological method to pre-dry lumber containing wetwood is a new concept introduced in this project. Wetwood is formed by bacteria growth inside normal wood. Some fungi are able to kill bacteria and to utilize foetid liquid produced by these micro-organisms. Consequently, the permeability of wetwood can be increased and the lumber drying rate can be improved. The present project intends a research on biological method to pre-dry lumber containing wetwood, and to evaluate efficacy and economic benefit of such a biological treatment. Wetwood of balsam fir, sub-alpine fir and aspen was cultured on nutrient media, and several species of bacteria and yeasts were isolated. The bacteria and yeasts were re-inoculated on normal wood of balsam fir. All inoculated micro organisms caused wetwood formation in 2 weeks. The MC of the inoculated wood blocks increased from 41% to 220-240%, whereas the control samples without inoculation reached only 110%. When control samples were dried to a MC of 13%, the inoculated wood samples still had MCs between 80% and 105%. The selection of biological control agents was conducted on both agar plates and on balsam fir wetwood blocks, and 2 fungal candidates demonstrated promising results. The field test showed that pre-treating balsam fir wetwood lumber with the selected best biocontrol candidates, wood stain was reduced by 94%, warping reduced up to 13%, and checking reduced up to 30% compared with untreated controls. Drying time was reduced by 33% (24 hours) compared with drying fresh lumber. CT scanner was able to detect wetwood locations inside a piece of lumber, and the wetwood was identified in heartwood, sapwood or both wood tissues. After the bio-treatment, the wetwood contents of boards were significantly reduced. Economical analysis showed that the biological treatment would cost $4-7/Mfbm depending on treating method used. Reduction of 33% of drying time by the treatment in this study could save energy cost by $6-13/Mfbm depending on kiln drying energy used. The treatment could reduce lumber degrading loss by $8.5-37.4/Mfbm base on this study. The benefit of the treatment is significant, but will be affected by pre-drying operation, kiln type, energy use and drying schedule. The biological treated lumber is resistant to fungal infection during pre-drying period, and the lumber products are clean and free of moulds and stain infection. Acknowledgements We specifically would like to thank Pierre Lemieux, Scierie Leduc, for providing testing wetwood materials. We also appreciate the support and guidance provided by the project’s industry liaison officers: François Saillant, Natural Resources Canada; Léandre Bélanger, Domtar. Their participation was the key to the success of this project.
Wetwood
Seasoning - Predrying
Yeasts
Bacteria
Biological Control
Fungi
Documents
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Biological method to pre-dry lumber with wetwood

https://library.fpinnovations.ca/en/permalink/fpipub42290
Author
Yang, D.-Q.
Date
March 2005
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Yang, D.-Q.
Date
March 2005
Material Type
Research report
Physical Description
44 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Yeasts
Wetwoods
Seasoning
Bacteria
Series Number
General Revenue 4030
Location
Sainte-Foy, Québec
Language
English
Abstract
Wetwood, or water pocket, has higher moisture content and lower permeability than normal wood, which cause serious problems for lumber drying. The high moisture content of wetwood usually requires relatively long periods for adequate drying; consequently, it causes a high risk for developing checks, splits, crook, bow and twist of lumber in kiln drying. These problems have not been solved by any physical, chemical or mechanical methods yet. Using biological method to pre-dry lumber containing wetwood is a new concept introduced in this project. Wetwood is formed by bacteria growth inside normal wood. Some fungi are able to kill bacteria and to utilize foetid liquid produced by these micro-organisms. Consequently, the permeability of wetwood can be increased and the lumber drying rate can be improved. The present project intends a research on biological method to pre-dry lumber containing wetwood, and to evaluate efficacy and economic benefit of such a biological treatment. Trees of balsam fir, sub-alpine fir and aspen were felled and cut into lumber. Isolation of causal agents was conducted from wet pockets of these wood species by using peptone agar and malt extract agar media. A total of 319 cultures were obtained from the wetwood of these three wood species. Three bacteria and two yeasts were isolated from balsam fir wetwood, 2 bacteria and 1 yeast were more frequently isolated from aspen wetwood, and 2 bacteria and 5 yeasts were obtained from sub-alpine fir. Two bacteria were isolated from the wetwood of all 3 wood species: Shigella sonnei and Pseudomonas fluorescens. Other bacteria and yeasts isolated were identified as Aerococcus viridans, Chryseomonas luteol, Candida boidinli, C. zeylanoides, Cryptococcus albidus, C. laurentii, C. terreus, and Rhodotorula mucileginosa. In addition to these identified bacteria and yeasts, two other yeasts isolated from balsam fir and sub-alpine fir wetwood were unabile to be identified. Six bacteria and yeast isolates were re-inoculated on normal wood of balsam fir; they were A-a (a bacterium isolated from aspen and identified as Shigella sonnei), A-c (a yeast isolated from aspen and identified as Cryptococcus laurentii), B-a (a bacterium isolated from balsam fir and identified as Shigella sonnei), B-c (a mixture of 2 bacteria isolated from balsam fir and identified as Shigella sonnei and Aerococcus viridans), Y-2 (an unidentified yeast isolated from balsam fir), and SaB-2 (a bacterium isolated from sub-alpine fir and identified as Shigella sonnei). The result showed that all of these micro-organisms caused wetwood formation on inoculated normal wood samples in 2 weeks. This result indicates that wetwood formation in trees is not caused by only 1 micro-organism but is more likely caused by several species (either bacteria or yeasts) that can colonise well in the wood of trees. The moisture contents (MC) of the inoculated wood blocks increased from 41.2% to 220-240 %, whereas the MCs of the control samples submerged in a liquid culture medium without inoculation reached only 110%. When control samples were dried to a MC of 13%, the inoculated wood samples still had MCs between 80% and 105%. This result indicates that drying lumber containing wetwood will take double the time required to dry normal lumber without wetwood. An antagonist test using fungal candidates was conducted on agar plates. In this test, 6 potential fungal antagonists and 6 wetwood causal agents (WCA) were used. The six fungal antagonists were Gliocladium roseum (Forintek bioprotectant), a white isolate of Ophiostoma piliferum (Cartapip), a white isolate of Ceratocystis resinifera (an anti-sapstain biological agent produced by Chantal Morin at Laval University), Oidium sp.A (a white fungus in Deuteromycetes isolated from Jack pine logs, DP3/5B-3a, 1998), Oidium sp. B (a white fungus in Deuteromycetes isolated from balsam fir logs, DF3/1B-1b, 1998), and Phaeotheca dimorphospora (a biological control agent of tree disease from Laval University). The six wetwood causal agents were A-a (a bacterium isolated from wetwood of aspen), A-c (a yeast isolated from wetwood of aspen), B-a (a bacterium isolated from wetwood of balsam fir), Y-2 (a yeast isolated from wetwood of balsam fir), SaB-2 (a bacterium isolated from wetwood of sub-alpine fir), and SaY-4 (a mixture of a yeast and a bacterium isolated from wetwood of sub-alpine fir). The results showed that Oidium sp.A and Oidium sp.B were the most effective against all 6 WCA inoculated; they reduced growth of the WCA in 7 days and completely absorbed colonies of WCA in 11 days. G. roseum, O. piliferum, and C. resinifera were moderately effective against 5 WCAs, but not effective on bacterium A-a that was isolated from aspen wetwood. P. dimorphospora was the least effective against any of these WCA. The three promising fungal antagonists, Oidium sp., G. roseum and the white isolate of O. piliferum, selected from agar plate test were used for a following antagonist test on balsam fir wetwood blocks in the laboratory conditions. This test was conducted on small wetwood samples (2 x 4 x 1 inch) in incubators at 25°C and two relative humidity ranges (100% and 75% RH). The results showed that all these three fungi were able to establish on wood surfaces and able to reduce wetwood contents. At 25°C and 75% RH, Oidium sp. was the most effective to reduce wetwood content in samples, followed by G. roseum, and then by O. piliferum. G. roseum and Oidium sp. not only reduce wetwood content, but also inhibit mold growth and wood stain, compared with untreated control samples. At 25°C and 100% RH, the moisture contents of treated and untreated samples were not changed in any week of the testing period. This result indicates that biological pre-dry wetwood samples should not be conducted at this high relative humidity condition. A test was conducted to investigate the ability of Oidium sp., the wetwood control candidate, against sapstaining fungi on wood. The results showed that if balsam fir wood wafers were inoculated with Oidium sp. 3 days before the staining fungi, no staining fungi grew on these samples. If wood wafers were inoculated with Oidium sp. and staining fungi at the same time, samples were covered by both Oidium sp. and the staining fungus Ophiostoma piceae in a ratio of 50 to 50%. If wood wafers were inoculated with the staining fungi 3 days before Oidium sp., samples were absolutely covered by the staining fungus and fully stained.
Wetwood
Seasoning - Predrying
Yeasts
Bacteria
Biological Control
Fungi
Documents
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Biological method to pre-dry lumber with wetwood

https://library.fpinnovations.ca/en/permalink/fpipub38957
Author
Yang, D.-Q.
Date
March 2006
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Yang, D.-Q.
Date
March 2006
Material Type
Research report
Physical Description
67 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Yeasts
Wetwoods
Seasoning
Bacteria
Series Number
General Revenue Project No. 4030
4030
Location
Québec, Québec
Language
English
Abstract
Wetwood, or water pocket, has higher moisture content and lower permeability than normal wood, which cause problems for lumber drying. The high moisture content of wetwood usually requires relatively long periods for adequate drying; consequently, it causes a high risk for developing checks, splits, crook, bow and twist of lumber in kiln drying. These problems have not been solved by any physical, chemical or mechanical methods yet. Using biological method to pre-dry lumber containing wetwood is a new concept introduced in this project. Wetwood is formed by bacteria growth inside normal wood. Some fungi are able to kill bacteria and to utilize foetid liquid produced by these micro-organisms. Consequently, the permeability of wetwood can be increased and the lumber drying rate can be improved. The present project intends a research on biological method to pre-dry lumber containing wetwood, and to evaluate efficacy and economic benefit of such a biological treatment. Trees of balsam fir, sub-alpine fir and aspen were felled and cut into lumber. Isolation of causal agents was conducted from wet pockets of these wood species by using peptone agar and malt extract agar media. A total of 319 cultures were obtained from the wetwood of these three wood species. Three bacteria and two yeasts were isolated from balsam fir wetwood, 2 bacteria and 1 yeast were more frequently isolated from aspen wetwood, and 2 bacteria and 5 yeasts were obtained from sub-alpine fir. Two bacteria were isolated from the wetwood of all 3 wood species: Shigella sonnei and Pseudomonas fluorescens. Other bacteria and yeasts isolated were identified as Aerococcus viridans, Chryseomonas luteol, Candida boidinli, C. zeylanoides, Cryptococcus albidus, C. laurentii, C. terreus, and Rhodotorula mucileginosa. In addition to these identified bacteria and yeasts, two other yeasts isolated from balsam fir and sub-alpine fir wetwood were unabile to be identified. Six bacteria and yeast isolates were re-inoculated on normal wood of balsam fir; they were A-a (a bacterium isolated from aspen and identified as Shigella sonnei), A-c (a yeast isolated from aspen and identified as Cryptococcus laurentii), B-a (a bacterium isolated from balsam fir and identified as Shigella sonnei), B-c (a mixture of 2 bacteria isolated from balsam fir and identified as Shigella sonnei and Aerococcus viridans), Y-2 (an unidentified yeast isolated from balsam fir), and SaB-2 (a bacterium isolated from sub-alpine fir and identified as Shigella sonnei). The result showed that all of these micro-organisms caused wetwood formation on inoculated normal wood samples in 2 weeks. This result indicates that wetwood formation in trees is not caused by only 1 micro-organism but is more likely caused by several species (either bacteria or yeasts) that can colonise well in the wood of trees. The moisture contents (MC) of the inoculated wood blocks increased from 41.2% to 220-240 %, whereas the MCs of the control samples submerged in a liquid culture medium without inoculation reached only 110%. When control samples were dried to a MC of 13%, the inoculated wood samples still had MCs between 80% and 105%. This result indicates that drying lumber containing wetwood will take double the time required to dry normal lumber without wetwood. An antagonist test using fungal candidates was conducted on agar plates. In this test, 6 potential fungal antagonists and 6 wetwood causal agents (WCA) were used. The six fungal antagonists were Gliocladium roseum (a bioprotectant developed by Forintek), a white isolate of Ophiostoma piliferum (a fungus used in a commercial bioprotectant, Cartapip), a white isolate of Ceratocystis resinifera (an anti-sapstain biological agent used by Chantal Morin at Laval University), Geotrichum sp.A (a white fungus in Deuteromycetes isolated from Jack pine logs, DP3/5B-3a, 1998), Geotrichum sp. B (a white fungus in Deuteromycetes isolated from balsam fir logs, DF3/1B-1b, 1998), and Phaeotheca dimorphospora (a biological control agent of tree disease from Laval University). The six wetwood causal agents were A-a (a bacterium isolated from wetwood of aspen), A-c (a yeast isolated from wetwood of aspen), B-a (a bacterium isolated from wetwood of balsam fir), Y-2 (a yeast isolated from wetwood of balsam fir), SaB-2 (a bacterium isolated from wetwood of sub-alpine fir), and SaY-4 (a mixture of a yeast and a bacterium isolated from wetwood of sub-alpine fir). The results showed that Geotrichum sp.A and Geotrichum sp.B were the most effective against all 6 WCA inoculated; they reduced growth of the WCA in 7 days and completely absorbed colonies of WCA in 11 days. G. roseum, O. piliferum, and C. resinifera were moderately effective against 5 WCAs, but not effective on bacterium A-a that was isolated from aspen wetwood. P. dimorphospora was the least effective against any of these WCA. The three promising fungal antagonists, Geotrichum sp., G. roseum and the white isolate of O. piliferum, selected from agar plate test were used for an antagonist test on balsam fir wetwood blocks in the laboratory conditions. This test was conducted on small wetwood samples (2 x 4 x 1 inch) in incubators at 25°C and two relative humidity ranges (100% and 75% RH). The results showed that all these three fungi were able to establish on wood surfaces and able to reduce wetwood contents. At 25°C and 75% RH, Geotrichum sp. was the most effective to reduce wetwood content in samples, followed by G. roseum, and then by O. piliferum. G. roseum and Geotrichum sp. not only reduce wetwood content, but also inhibit mold growth and wood stain, compared with untreated control samples. At 25°C and 100% RH, the moisture contents of treated and untreated samples were not changed in any week of the testing period. This result indicates that biological pre-dry wetwood samples should not be conducted at this high relative humidity condition. A test was conducted to investigate the inhibitory ability of Geotrichum sp., the wetwood control candidate, against sapstaining fungi on wood. The results showed that if balsam fir wood wafers were inoculated with Geotrichum sp. 3 days before the staining fungi, no staining fungi grew on these samples. If wood wafers were inoculated with Geotrichum sp. and staining fungi at the same time, samples were covered by both Geotrichum sp. and the staining fungus Ophiostoma piceae in a ratio of 1:1. If wood wafers were inoculated with the staining fungi 3 days before Geotrichum sp., samples were absolutely covered by the staining fungus and fully stained. A study on environmental effects on the growth of Geotrichum sp., the wetwood control agent, showed that this fungus started growth at 5°C, had optimal growth between 20-25°C, stopped growth at 30°C, and died at 40°C. Geotrichum sp. had a wide range of pH requirement and grew well in agar medium at pHs between 3 and 10. Geotrichum sp. started to grow at 29% MC, and the speed of the growth increased along with the increase of MC in wood. The best fungal growth of Geotrichum sp. was observed on wood blocks containing 56% MC. Geotrichum sp. was able to grow on wood of jack pine, black spruce, balsam fir, sub-alpine fir and aspen, but it grew better on wood of jack pine, balsam fir and black spruce than on sub-alpine fir and aspen. Geotrichum sp. was able to grow together with an anti-sapstain fungus, Gliocladium roseum, without any antibiotic or incompatible growth reaction. In the laboratory conditions, the biological treated boards reduced wood MC by 22-37% more than untreated boards. Untreated boards were fully covered by molds and stain after 8 weeks in storage, and 0% of boards was acceptable for use. The biological treated boards were less affected, with 35-75% of pieces acceptable. The time required for drying biological treated boards was estimated reducing by 10.5 hours compared with untreated controls. After drying, the biological treated boards reduced the rate of crook, bow and twist by 5-20%, but increased the rate of split and check by 5-12%, compared with untreated controls. The total deformation rate was reduced up to 5% by the best biological treatment. In the field conditions, untreated boards were 100% affected by molds and stain after 8 weeks in storage, whereas the best biological treated boards were only affected by 6%. Drying biological treated and untreated boards took similar times, but it was estimated reducing drying time by 48 hours compared with fresh boards. Compared with untreated controls, the biological treated boards reduced the rate of crook, bow and twist by 2-13%, and reduced the rate of split and check by 3-30%. The total deformation rate was reduced by 5-22%, depending on the treatments. CT scanner was able to detect wetwood locations inside a piece of lumber, and the wetwood present in either heartwood, sapwood or both wood tissues. After the bio-treatment, the wetwood contents of boards were significantly reduced.
Wetwood
Seasoning - Predrying
Yeasts
Bacteria
Biological Control
Fungi
Documents
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Biological modification of biomass & lignosulfonate for bio-composite application

https://library.fpinnovations.ca/en/permalink/fpipub3100
Author
Yang, D.-Q.
Date
November 2013
Edition
39757
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Yang, D.-Q.
Contributor
Canadian Forest Service.
Date
November 2013
Edition
39757
Material Type
Research report
Physical Description
7 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Lignosulfonates
Biomass
Wood composites
Series Number
301006260
E-4857
Location
Québec, Québec
Language
English
Abstract
Hardwood flour was biologically converted with 3 fungal species, and ammonium lignosulfonate was biologically modified with 3 enzyme cocktails. Ten types of panels were made of bio-modified or unmodified wood flour and ammonium lignosulfonate. All panels were manufactured at target density (850 kg/m3), temperature (220°C), pressure (300 psi) and pressing time (220 sec) without any resin and additives. Among all formulations, the biomaterials, consisted of bio-modified hardwood flour by the fungal specie 332A, or bio-modified ammonium lignosulfonate by enzymes extracted from 76A and 329A, were most effective and showed significantly higher internal bonding (IB) strengths. Further investigation of the bio-modification of the kraft lignin for bio-composites is conducted in 2013-2014 financial year (ongoing) and will be reported in 2013-2014.
Documents
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Biotechnology to improve mould, stain and decay resistance of OSB

https://library.fpinnovations.ca/en/permalink/fpipub42231
Author
Yang, D.-Q.
Wang, Xiang-Ming
Wan, Hui
Date
March 2004
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Yang, D.-Q.
Wang, Xiang-Ming
Wan, Hui
Contributor
Canada. Canadian Forest Service
Date
March 2004
Material Type
Research report
Physical Description
46 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Materials
Series Number
Canadian Forest Service No. 31
Location
Sainte-Foy, Québec
Language
English
Abstract
Oriented strand board (OSB) is widely used in house construction in North America. In Canada, OSB panels are commonly made of aspen strands and are susceptible to mould and decay when they get wet. Building envelope failures due to mould, decay or poor construction practices can negatively impact the image of wood. This can lead to product substitution that in turn can affect the wood industry’s overall competitiveness. To ensure durability of OSB panels, the most important consideration is the use of mould- and decay-resistant panels to prevent fungal attack. Using low environmental impact technology to improve the durability of OSB products could have market-related advantages over using chemical protection products. This project aimed to develop technologies for protecting OSB raw materials from biodegradation and to explore biological pre- or post-treatments to increase the durability of panels so they would better resist mould, stain and decay. The project was divided into three parts. Part one involved developing a biological technology to protect OSB raw materials from biodegradation. In this part, aspen, red maple and yellow birch trees, which are commonly used to make OSB in Canada, were felled in May and cut into 4-foot logs. These logs were then equally divided into two groups (16 logs each) with one group keeping its bark and the other having it removed. These debarked and “bark-on” logs were further divided into two groups, each containing 8 logs. One group of logs was treated with a bioprotectant and another group served as a control. The treated and untreated logs were stored separately in Forintek’s yard. Two inspections were conducted, one at the end of the growth season (in October after a 5-month storage period) and the other after one year. During each inspection, four logs from each test group were examined for fungal degradation (mould, stain and decay), and then cut into strands to be used for manufacturing panels. The panels’ physical and mechanical properties and mould resistance were evaluated. The second part involved developing a biological pre- or post-treatment technology by using naturally resistant wood species to increase the durability of panels so they would better resist mould, stain and decay. In this part, a series of tests were conducted using various wood species. These tests included a) determining the antifungal properties of bark from various wood species; b) using white cedar to improve panel durability; c) optimizing manufacturing conditions for producing durable panels with white cedar; d) using other wood species to produce mould-resistant panels; and e) post-treating panels with extracts of durable wood species. The third part consists of developing a biological pre- or post-treatment technology by using fungal antagonists to increase the durability of panels against mould, stain and decay. This part will be conducted in the 2004-2005 fiscal year, and results will be included in next year’s report. The results of the first part on the protection of raw materials showed that all untreated logs, with or without bark, were seriously degraded by moulds, stain and decay fungi after a summer storage period of five months. The logs with bark were more degraded than the debarked logs, and the log ends were more degraded than the middle sections. After summer storage, 55% to 83% of the wood was degraded in untreated logs. The biological treatment was effective, only 4% to 16% of the wood in treated logs was affected by various fungi after a five-month storage period. Furthermore, the biological treatment was more effective on logs without bark than logs with bark, and more effective on yellow birch and aspen than on red maple. After one year in storage, the total infection rates of untreated logs ranged from 68% to 91%, whereas the rate for biologically treated logs ranged from 27% to 49%. Among these treated logs, the logs ends were degraded from 31% to 62%, whereas the middle sections were degraded from 7% to 26%. Strands cut from untreated logs contained 50% to 75% of grey or blue stained strands, whereas those cut from biologically treated logs contained 10% to 25% of such strands. Panels made using biologically treated logs had the lowest TS and WA values compared with panels made using fresh-cut logs and untreated stored logs. The other physical and mechanical properties of the various panels made for this test were comparable. The antifungal properties of bark from six wood species (aspen, red maple, yellow birch, balsam fir, white spruce and white cedar) were investigated in the second part of this research project. Based on the colony growth rate of moulds, stain and decay fungi on bark-extract-agar media, white spruce bark was the best at inhibiting growth of these fungi, followed by red maple bark. White cedar and balsam fir bark somewhat inhibited certain fungi tested. Aspen and yellow birch bark did little or nothing at all to inhibit fungal growth. The research also showed that the white cedar heartwood-extract-agar medium not only inhibited decay fungi growth, but also inhibited the growth of moulds and staining fungi. The bark-extract-agar medium of this wood species was less effective in inhibiting fungal growth than the heartwood was. Three-layer panels made using white cedar heartwood strands in the face layers and aspen strands in the core layer at a ratio of 25:0:25 were mould and decay resistant, but the panels “blew” easily during manufacturing and their mechanical properties were not satisfying. The overall mould infection rate on white cedar heartwood-faced panels was 0.8, which indicated that the panel was mould resistant. White spruce heartwood-faced panels were highly mould resistant and moderately decay resistant. The overall mould infection rate on white spruce heartwood-faced panels was only 0.2 after 8 weeks of exposure to high humidity environmental conditions. In addition to being mould resistant, white spruce heartwood-faced aspen panels also had better IB, MOR and MOE properties, compared with aspen panels. The panels with black spruce in surface layer had mechanical and mould-resistance properties that were similar to those with white spruce in surface. The panels with surface layer of Eastern larch heartwood were non-resistant to moulds and slightly resistant to decay, but they had better IB, TS and WA properties compared with the other types of panels. The overall mould infection rate on the panel with surface layer of Eastern larch heartwood was 3.7, which was similar to the rate for aspen control panels. Aspen panels (serving as control panels) were seriously affected by moulds with overall mould infection rates ranging from 3.8 to 4.9. Aspen panels with surface layer from whole-wood strands (using both sapwood and heartwood) from white cedar, in a ratio of 25:50:25 and pressed at 220°C for 150 seconds, were well bonded and had IB, TS, WA and MOE values that were similar to those of aspen control panel, but with a higher MOR. All the panels’ properties met the requirements of the standard. This type of panel also was the least infected by moulds, especially in the face layers which rated a 0.2. The panel sides were moderately infected, rating a 2.6, this occurring mostly in the middle layer of aspen strands. The overall rate of this type of panel was 1.0, which indicated that the panels were resistant to mould infection. This type of panel was also highly resistant to brown rot and moderately resistant to white rot. Panels made of steam-treated white cedar whole-wood strands and aspen strands at a ratio of 3:7 based on oven-dry weight also had low infection rates: the average face infection rate was 1.2; the side infection was 2.4 and the overall rate was 1.6. Compared with aspen panels, this type of panel also had high MOR and MOE values and low TS and WA values. In the case of white cedar whole-wood strands faced aspen panels, when the pressing time was increased from 160 seconds to 180 seconds at 200°C, the panels’ IB strength and MOE increased whereas the panels’ TS, WA and MOR decreased. By increasing the pressing temperature from 200°C to 240°C and pressing for 160 seconds, the panels’ IB strength, MOR and MOE increased and the panels’ TS and WA decreased sharply. At a pressing temperature of 240°C and a pressing time of 180 seconds, the panels’ IB strength, MOR and MOE increased significantly and the panels’ TS and WA decreased significantly. These data showed that aspen panels with surface layer from white cedar whole strands at a ratio of 25:50:25 and pressed at 240°C for 180 seconds had the best mechanical and physical properties. All panel samples were slightly infected by moulds on the faces. A fair amount of mould occurred on the sides of panels pressed at 200°C for 160 seconds and 180 seconds and those pressed at 240°C for 180 seconds. The panels pressed at 240°C for 160 seconds were the least infected by mould (with an infection rate of 0.3). Panels pressed at 200°C had a white-yellowish colour, whereas those pressed at 240°C were yellow-brownish and darker than those pressed at 200°C. Panels pressed at 200°C for 160 or 180 seconds and those pressed at 240°C for 160 seconds were highly decay resistant, especially to brown rot. The decay resistance of panels pressed at 240°C for 180 seconds was lower compared with the other panels. Compared with aspen panels, panels with surface layer from steam-treated white cedar strands and aspen strands at a ratio of 7:3 based on oven-dry weight had higher TS, WA, MOR and MOE values and a similar IB value. Panels with surface layer from steam-treated white cedar strands and aspen strands at a ratio of 4:6 based on oven-dry weight had the highest IB value. A reduction in mould and decay resistance corresponded to a reduction in the proportion of white cedar strands in the face layers. The overall mould growth rate was 1.27 on panels with surface layer from steam-treated white cedar strands and aspen strands at a ratio of 4:6, 0.6 on panels with surface layer from steam-treated white cedar strands and aspen strands at a ratio of 7:3, and 0.4 on panels faced with 100% white cedar whole strands, respectively. Panels made from 100% white cedar whole-wood strands or a mixture of whole-wood strands of white cedar and aspen (50:50) in the core layer were “blown” after pressing. Panels made from a mixture of white cedar and aspen strands at a ratio of 25:75 in the core layer and aspen strands in the face layers had superior IB, MOR and MOE values than other panels. However, their TS and WA values were also higher than those of white cedar-faced panels. Panels made from a mixture of white cedar and aspen strands at a ratio of 25:75 in the core layer and white cedar strands in the face layers had the worst physical and mechanical properties among all the panels made for this test. The tests results for mould showed that panels made with a mixture of white cedar and aspen strands at a ratio of 25:75 in the core layer and aspen strands in the face layers ware seriously attacked by moulds and had an overall mould growth rate of 4.2. No mould infection was found on panels made from 100% white cedar strands. Panels made from a strand mixture of white cedar (50%) and aspen (50%) in the core layer and white cedar strands in the face layers had little mould infection. The overall mould growth rate on this type of panel was 0.2. Compared with the control aspen panels, aspen panels with surface layer from white cedar whole-wood strands at a ratio of 15:70:15 had similar IB and TS values, a lower WA value and higher MOR and MOE values. When the white cedar strand proportion in the face layer was increased from 15% to 25%, the panels’ IB strength and WA decreased, but their MOR and MOE values increased. Panels with surface layer from white cedar strands at a ratio of 15:70:15 had little infection from moulds on the face and bottom layers, but had an increased infection rate on all four sides. The average overall infection rate of this type of panel was 0.5. When the white cedar in the panels’ face layer was increased from 15% to 25%, the average infection rate on the panels’ faces was still 0.1, but the infection rate of the panels’ sides dropped from 1.2 to 1.0. The overall rate was 0.4. In terms of decay resistance, panels with surface layer from 25% white cedar strands performed better than those with surface layer from 15% white cedar.
Composite materials - Durability
Biotechnology
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Biotechnology to improve mould, stain and decay resistance of OSB

https://library.fpinnovations.ca/en/permalink/fpipub42285
Author
Yang, D.-Q.
Wang, Xiang-Ming
Wan, Hui
Date
March 2005
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Yang, D.-Q.
Wang, Xiang-Ming
Wan, Hui
Contributor
Canada. Canadian Forest Service
Date
March 2005
Material Type
Research report
Physical Description
75 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Materials
Series Number
Canadian Forest Service No. 31
Location
Sainte-Foy, Québec
Language
English
Abstract
This project aimed to develop technologies for protecting OSB raw materials from biodegradation and to explore biological pre- or post-treatments to increase the durability of panels so they would better resist mould, stain and decay. The project was conducted in five parts. Part one involved developing a biological technology to protect OSB raw materials from biodegradation. The results of this part of the work showed that all untreated logs, with or without bark, were seriously degraded by moulds, stain and decay fungi after a summer storage period of five months. The logs with bark were more degraded than the debarked logs, and the log ends were more degraded than the middle sections. After summer storage, 55% to 83% of the wood was degraded in untreated logs. The biological treatment was effective, only 4% to 16% of the wood in treated logs was infected by various fungi after a five-month storage period. Furthermore, the biological treatment was more effective on logs without bark than logs with bark, and more effective on yellow birch and aspen than on red maple. After one year in storage, the total infection rates of untreated logs ranged from 68% to 91%, whereas the rate for biologically treated logs ranged from 27% to 49%. Strands cut from untreated logs contained 50% to 75% of grey or blue stained strands, whereas those cut from biologically treated logs contained 10% to 25% of such strands. Panels made using biologically treated logs had the lowest thickness swelling (TS) and water absorption (WA) values compared with panels made using fresh-cut logs and untreated stored logs. The other physical and mechanical properties of the various panels made for this test were comparable. For the mould resistance, all panels made from fungal treated logs had better mould resistance than those made from freshly cut and untreated logs. Panels made of strands cut from fungal treated debarked logs had better mould resistance than the panels made from fungal treated bark-on logs. The second part of the research consisted of investigating antifungal properties of barks from various wood species. In this part, antifungal properties of barks from 6 wood species: aspen, red maple, yellow birch, balsam fir, white spruce and white cedar were screened in a laboratory test against moulds, staining fungi, white-rot and brown-rot fungi. Based on the colony growth rate of moulds, stain and decay fungi on bark-extract-agar media, white spruce bark was the best at inhibiting growth of these fungi, followed by red maple bark. White cedar and balsam fir bark somewhat inhibited certain fungi tested. Aspen and yellow birch bark did little or nothing at all to inhibit fungal growth. The third part involved developing a biological treatment technology by using naturally resistant wood species to increase the durability of panels so they would better resist mould, stain and decay. In this part, a series of tests were conducted using various wood species. These tests included a) using white cedar to improve panel durability; b) optimizing manufacturing conditions for producing durable panels with white cedar; and c) using other wood species to produce mould-resistant panels. The results showed that three-layer panels made using white cedar strands in the face layers and aspen strands in the core layer at different ratios were mould and decay resistant. White spruce heartwood-faced panels were highly mould resistant and moderately decay resistant. In addition to being mould resistant, white spruce heartwood-faced aspen panels also had better internal bond (IB), modulus of rupture (MOR) and modulus of elasticity (MOE) properties, compared with aspen panels. The panels with black spruce in surface layer had mechanical and mould-resistance properties that were similar to those with white spruce in surface. The panels with surface layer of Eastern larch heartwood were non-resistant to moulds and slightly resistant to decay, but they had better IB, TS and WA properties compared with the other types of panels. The fourth part of the research consisted of developing a biological treatment technology by using fungal antagonists to increase the durability of panels against mould, stain and decay. In this part, two major tests were conducted using various fungal species. They were: a) treating wood strands with three antagonistic fungi, Gliocladium roseum, Phaeotheca dimorphospora and Ceratocystis resinifera, to increase OSB panel durability; and b) treating wood strands with a lignin-degrading fungus, Coriolus hirsutus, to reduce OSB resin usage. The results of this part of the work showed that all of the 4 fungal species used grew well on aspen strands in four weeks, and strands in all treatments had normal wood color after incubation. For IB property, panels made of fungal treated strands were better or similar to the control panels. Panels made of fungal treated strands had higher TS and WA values than untreated control panels. For mechanical properties, panels made of fungal treated strands had a slight lower dry MOR and higher wet MOR than control panels. For mould resistance, panels made of fungal treated strands were infected by moulds one week later than the untreated control panels, and reduction of mould infection rates was detected on fungal treated panels within 6 weeks. After 6 weeks, all panels, treated or untreated, were seriously infected by moulds. Reducing resin usage in fungal treated panels did not affect panel density. Compared with untreated control panels, the IB property of panels made of fungal treated strands was slightly increased by using normal dosage of resin or a reduced dosage by 15%, but slightly decreased with a resin reduction by 30%. There was a negative linear correlation of the panel TS and WA properties with resin reduction by using fungal treated strands. For the mechanical properties, panels made of fungal treated strands had lower dry MOR and MOE values, but higher wet MOR values (except for a resin reduction of 30%) than panels made of untreated strands. The fifth part involved protecting OSB against mould and decay by post-treatment of panels with natural extracts from durable wood species and from fungal antagonists. In this part, three tests were conducted using extracts of white cedar heartwood and extracts of a fungal antagonist. These tests were: a) screening antifungal properties of natural extracts against mould and decay fungi; b) post-treating OSB panels with white cedar heartwood extracts and finishing coats; and c) post-treating OSB panels with fungal metabolites. The results of this part of the work showed that the mycelial growth of all fungi tested (moulds, staining fungi, white-rot and brown-rot fungi) was inhibited by the extracts of white cedar heartwood and extracts of the fungal antagonist, P. dimorphospora, on agar plates. Panel samples dipped with the cedar extracts got slight mould growth on the 2 faces and moderate mould growth on the 4 sides, whereas the panel samples dip-treated with the fungal extracts got the minimal mould infection among the panels tested. The results of the mould test on the post-treated panels with extracts of white cedar heartwood and three coating products showed that slight or no mould growth was detected on any sample dip-treated with the extracts and then brushed with finishing coats. The decay test showed that most post-treated samples had less weight losses than untreated control samples.
Composite materials - Durability
Biotechnology
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Biotechnology to improve mould, stain and decay resistance of OSB

https://library.fpinnovations.ca/en/permalink/fpipub42205
Author
Yang, D.-Q.
Date
August 2003
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Yang, D.-Q.
Contributor
Canada. Canadian Forest Service
Date
August 2003
Material Type
Research report
Physical Description
4 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Materials
Series Number
CFS Simple Progress Report No. 31
Location
Sainte-Foy, Québec
Language
English
Abstract
Composite materials - Durability
Biotechnology
Documents
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