Influence of type and amount of lignin on decay by Coriolusversicolor

1982 ◽  
Vol 12 (2) ◽  
pp. 435-438 ◽  
Author(s):  
Terry L. Highley

Samples of a hardwood containing primarily coniferous (guaiacyl) lignin and hardwoods and softwoods with normal amounts of guaiacyl and syringyl lignin were degraded by the white-rot fungus Coriolusversicolor (L. ex Fr.) to assess the influence of type and amount of lignin on rate of decay. Lignin and carbohydrate losses were compared for the woods at various degrees of weight loss. The hardwood with coniferous lignin was degraded in a manner similar to the softwoods, indicating that the type of lignin is more a factor in the slower rate of C. versicolor decay of softwoods than is the amount of lignin, or the anatomical structure itself.

BioResources ◽  
2010 ◽  
Vol 6 (1) ◽  
pp. 59-69
Author(s):  
Seyyed Khalil Hosseini Hashemi ◽  
Ahmad Jahan Latibari

Walnut (Juglans regia L.) heartwood extractives were identified and their potential for protection of poplar wood was evaluated. Test specimens were prepared from poplar wood (Populus nigra L.) to meet BS 838:1961 requirements. Samples were impregnated with heartwood extractive solution (1.5, 2.5, and 3.5% w/w in ethanol-toluene), followed by 5 hours vacuum desiccator technique to reach complete saturation. Impregnated specimens were exposed to white-rot fungus (Trametes versicolor) for 14 weeks according to BS 838:1961 applying the kolle-flask method. The weight loss of samples was determined after exposure to white-rot fungus. The highest weight loss (36.96%) was observed for untreated control samples and the lowest weight loss (30.40%) was measured in samples treated with 1.5% extractives solution. The analyses of the extracts using GC/MS indicated that major constituents are benzoic acid,3,4,5-tri(hydroxyl) and gallic acid (44.57 %). The two toxic components in the heartwood are juglone (5.15 %) and 2,7-dimethylphenantheren (5.81 %).


2021 ◽  
Vol 71 (1) ◽  
pp. 46-57
Author(s):  
Ying Gao ◽  
Shiyi Mei ◽  
Xingxia Ma ◽  
Xinmiao Meng

Abstract For this study, spruce–pine–fir (Picea–Pinus–Abies [SPF]) specification material, oriented strand board (OSB), and domestic twisted nails that were driven vertically and perpendicular-to-grain were selected. Referring to GB/T 13942.1-2009, nailed joints specimens were exposed both to white rot fungus and brown rot fungus for 1 month to 6 months. The monotonous loading test was applied to the specimens based on ASTM D1761-88. The holding power of the nails and weight loss of both OSB and SPF were investigated. Theoretical maximum load of the nailed joints was calculated according to Eurocode5. Results illustrated that the load, stiffness, and energy consumption of the nailed joints showed significant linear decline with the decay time. A linear decline of the ductility coefficient was not obvious, and there was no obvious difference between white rot fungus and brown rot fungus. Effect of decay on the OSB was much greater than the impact on the SPF. The decay grade of the nailed joints was established according to the linear relationship between weight loss and maximum load. Based on Eurocode5, the study calculated the maximum load of the nailed joints and introduced the correction coefficient γ to better predict the maximum load.


Holzforschung ◽  
2011 ◽  
Vol 65 (6) ◽  
pp. 883-888 ◽  
Author(s):  
Olaf Schmidt ◽  
Dong Sheng Wei ◽  
Walter Liese ◽  
Elisabeth Wollenberg

Abstract The degradation of several Asian bamboo species by white-, brown-, and soft-rot fungi was investigated under laboratory conditions by means of different test methods. Severe deterioration was caused by all three fungi types. The bamboo species differed in durability. Samples from 6 months young culms decayed more than older ones. There were no significant differences between 1- and 3-year-old culms. Samples taken from the culm top were more vulnerable to decay than those from the bottom. Wet bamboo samples with soil contact were especially degraded by the white-rot fungus Schizophyllum commune, whereas the brown-rot fungus Coniophora puteana produced the greatest mass loss in drier samples. The sealing of bamboo crosscut ends reduced the rate of decay.


1970 ◽  
Vol 46 (2) ◽  
pp. 225-230 ◽  
Author(s):  
M Ashaduzzaman ◽  
AK Das ◽  
I Kayes ◽  
MI Shams

Natural decay resistance of two fast growing timber species, Acacia auriculiformis Cunn. ex. Benth. and Dalbergia sissoo Roxb. grown in Bangladesh was evaluated by adopting an accelerated decay test method. The wood specimens were exposed to a white rot fungus, Schizophyllum communie for 12 weeks. The natural decay resistance was determined by the weight loss percentage of the tested wood specimens. The weight losses were found 2.0% and 4.37% in heartwood, and 22.19% and 13.61% in sapwood of A. auriculiformis and D. sissoo, respectively. In both the species, the weight loss was significantly higher in sapwood than heartwood. This means that heartwood was more resistant than sapwood. The weight loss significantly increased from bottom to top. Significant variation has been observed in weight loss between A. auriculiformis and D. sissoo both in heartwood and sapwood. The wood of A. auriculiformis and D. sissoo were classified as naturally durable following the standard classification of natural durability. Key words: Decay resistance; Acacia auriculiformis; Dalbergia sissoo; Schizophyllum communie; Accelerated decay test DOI: http://dx.doi.org/10.3329/bjsir.v46i2.8189 Bangladesh J. Sci. Ind. Res. 46(2), 225-230, 2011


Holzforschung ◽  
2006 ◽  
Vol 60 (1) ◽  
pp. 104-109 ◽  
Author(s):  
Takeshi Furuno ◽  
Fuyuki Wada ◽  
Sulaeman Yusuf

Abstract Insoluble metaborates were formed by impregnating wood with borax and metallic salts, and the biological resistance of samples treated with metaborates was evaluated. The double-diffusion process was carried out to form metaborate precipitates in sapwood specimens of Japanese cedar (Cryptomeria japonica). Water-saturated wood specimens were first impregnated by a saturated borax solution and then diffusion-penetrated with solutions of zinc sulfate or copper sulfate of different concentrations. In laboratory-scale termite tests of wood specimens treated with zinc and copper metaborates at five concentrations from 3% to 20% using a virulent subterranean termite (Coptotermes formosanus), metaborate-treated wood showed negligible weight loss, with high termite mortality at the lowest concentration of 3%. An additional termite test for treatments at lower concentrations of 1% and 2% revealed good termite resistance even with small weight gains of 2.3–6.7%. In field termite tests using a tropical dominant termite (Macrotermes gilvus) in Serpong, Indonesia, wood specimens of 2 cm (r)×2 cm (t)×10 cm (l) treated with metaborates at 5% and 20% showed little weight loss against termite attack for 2 months or more. In addition, in a decay test using a white-rot fungus (Trametes versicolor) and a brown-rot fungus (Fomitopsis palustris), metaborate-treated woods showed enhanced decay resistance. This superb enhancement of biological resistance against termite and decay attacks is considered to be attributable to the presence of metaborates containing effective components such as boron, zinc or copper in the cell walls, which were detected by EPMA observations.


2014 ◽  
Vol 703 ◽  
pp. 98-101
Author(s):  
Ju Wei Wang

Xylan preservative is a new type of wood preservatives ,which is not only harmless to humans and animals, but also no contaminates the environment. Through the extraction of corn cob xylan, anti-corrosion performance testing and compared with the CCA, the results shows that: white rot fungus specimen weight loss rates were: 2.53%, and CCA weight loss rates were 4.08%. In this paper, we carried out through cottonwoods of different states to measure, research and analyse the main chemical composition on their moisture content, benzene - alcohol extract content, lignin content and whole fiber content, which is for future improvement preservatives formulated to provide experimental data, through the comparison of chemical composition among different states of cottonwoods to find out how the effects of preservatives on cottonwood anticorrosive were. The experiments indicated that benzene-alcohol extractive contents of anticorrosion cottonwood and fresh cottonwood were close to 4.50% and 4.51%, while decayed cottonwood of benzene-alcohol content of drawn increased to 5.70%. Lignin contents of anticorrosion and fresh cottonwood were close: respectively, 22.10% and 22.55%, from 24.19% rotten cottonwood. The whole fiber content of Anticorrosion cottonwood, fresh cottonwood and decayed cottonwood were, respectively,66.62%, 84.55% and 64.19% .


2014 ◽  
Vol 703 ◽  
pp. 102-105
Author(s):  
Ju Wei Wang

Xylan preservative is harmless to humans and animals, contaminate the environment of new wood preservatives.This paper from bagasse, rice husk, corncob, xylan extracted from birch, testing the corrosion resistance of these four preservatives and CCA compared with the results show that: white rot fungus specimen weight loss rates were: Bagasse xylan: 2.41%, rice husk xylan: 2.65%, corn cob xylan: 2.53%, birch xylan: 2.33%, CCA rate of 4.08% weight loss.


2020 ◽  
pp. 096739112091534
Author(s):  
Behzad Kord ◽  
Nadir Ayrilmis ◽  
Mohammad Dahmardeh Ghalehno

Effects of fungal decay period on the technological properties of polypropylene/rice straw composites reinforced with different amount of carbon nanotubes (CNTs) were evaluated in this research work. The composite specimens were prepared using an internal mixer followed by compression molding. The specimens were then subjected to the fungal decay using white-rot fungus ( Coriolus versicolor) for 1, 2, 3, and 4 months. The degree of fungal attack was recorded by determining the weight loss of the specimens. The physical and mechanical properties including water uptake, flexural strength, and impact strength (IS) were investigated. The results indicated that the weight loss of the specimens was significantly reduced by increasing the CNT loading levels. The weight loss ratio of the specimens with the CNT was lower than that of the specimens without the CNT. The modulus of rupture, modulus of elasticity, and IS of the specimens exposed to the fungal degradation increased in the presence of CNT. Furthermore, the decayed specimens without CNT had higher water uptake than those of the specimens with CNT. This was attributed to the decrease in the number of cavities on the surface of the composites containing CNT. Based on the findings obtained from the present study, it was concluded that the amount of the CNT should be considered according to the severity and duration of the fungal exposure.


2012 ◽  
Vol 3 (1) ◽  
pp. 20-21
Author(s):  
A.Sangeetha A.Sangeetha ◽  
◽  
K.Thanigai K.Thanigai ◽  
Narasimhamurthy Narasimhamurthy ◽  
S.K.Nath S.K.Nath

2020 ◽  
Vol 93 (9) ◽  
pp. 289-292
Author(s):  
Yumi SHIMIZU ◽  
Shuma SATHO ◽  
Taro NAKAJIMA ◽  
Hiroaki KOUZAI ◽  
Kiminori SHIMIZU

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