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Search Results: 1 - 10 of 5050 matches for " Wood Decay Fungi (WDF) "
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BIODEGRADATION OF CELLULOSE BY WOOD DECAYING FUNGI
JAGRATI PARIHAR,C.K.TIWARI,AKHILESH AYACHI,R.K. VERMA
Journal of Applied Sciences in Environmental Sanitation , 2012,
Abstract: In the present study 212 specimens of wood decaying fungi were collected from Chhattisgarh, India, during survey in rainy season, 2009- 2010. These were identified, brought in pure culture by tissue culture method on Potato dextrose agar medium. Out of these, 33 species were screened and tested for cellulose degradation capability using filter paper cellulose. The ability of host fungus to utilize insoluble form of cellulose was measured. It was found that, all the 33 wood decaying fungi were able to decompose cellulose at varying degree. Biodegradation of cellulose and CAI were observed maximum with Navisporus floccosus whereas, Pyrofomes tricolor showing minimum biodegradation of cellulose and Flavodon flavus show minimum CAI. It is concluded that cellulose decomposition pattern was vary not only among the genera but also between the species of same genus.
Potentials of Liquefied CCB Treated Waste Wood for Wood Preservation
Miha Humar,Franc Budija,David Hrastnik,Bo?tjan Lesar
Drvna Industrija , 2011,
Abstract: Recovered wood is frequently contaminated with biocides and therefore its use is limited. Even more, wood, impregnated with classical chromated copper arsenate (CCA) preservatives is classified as a hazardous waste, therefore solutions for reuse or recovery of this material are sought. One of the options, discussed in this paper is liquefaction and further applications of liquefied wood containing biocide remainings. In order to elucidate this possibilty, spruce and beech wood was impregnated with liquefi ed CCB treated and untreaded spruce wood of various concentrations and exposed to wood decay fungi according to the EN 113 procedure. In paralel, the leaching experiments (ENV 1250-2) were performed as well. The results do not clearly show that liquefied wood is bio-inactive. In most cases the mass loss by fungal attack is decreased compared to the untreated controls. On the other hand, copper leaching from spruce wood, impregnated with the liquefi ed CCB treated wood was significantly reduced. Thus, there are indications that the liquefied wood could be utilized as a binding agent for inorganic biocides.
Biological Durability of Injection Moulded Wood Plastic Composite Boards
P.S. H`ng,A.N. Lee,C.M. Hang,S.H. Lee
Journal of Applied Sciences , 2011,
Abstract: The steadily growth of Wood Plastic Composite (WPC) in exterior applications resulted a need to understand their durability. In Malaysia, the durability of WPC is not only affected by mold and decay fungi as biodegradation agents but also due the termites attack. Therefore, this study was carried out to investigate the durability of WPC produced from different wood fine loadings (60, 65 and 70%) and MAPP (1, 2, 3 and 4%) concentration. The aim of this study is to determine the optimum WPC formulation associate with higher durability against biodegradation agents. Commercial polypropylene, wood fines and coupling agent premixed in dumper mixer for 30 min prior to extrusion process at temperature of 190°C using 110 mm counter-rotating twin-screw extruder. The premixed raw materials were then subjected to injection moulded using 40 ton press moulding machine and pressed into size of 30 mmx30 mm and 3 mm thick board. Biological durability tests were carried out according to ASTM D4445 for mold, ASTM method D 2017 for decay fungi and ASTM D 3345 for termites. From the result, 70% wood fine loading showed significantly lower durability due to the insufficient encapsulation of wood fine with polymer matrix. Higher percentage of coupling agent (MAPP) used in the WPC boards will provide higher durability of WPC. Conclusively, the optimum formulation for WPC i.e., 4% MAPP and 60% wood fine loading gave the highest protection against mold, decay fungi and termites.
Isolamento e sele??o de fungos causadores da podrid?o-branca da madeira em florestas de Eucalyptus spp. com potencial de degrada??o de cepas e raízes
Alonso, Sandra Kunieda de;Silva, Aderlan Gomes da;Kasuya, Maria Catarina Megumi;Barros, Nairam Félix de;Cavallazzi, José Renato Pereira;Bettucci, Lina;Lupo, Sandra;Alfenas, Acelino Couto;
Revista árvore , 2007, DOI: 10.1590/S0100-67622007000100016
Abstract: the aim of this work was to isolate native wood white-rot fungi from fungal fruit-bodies and eucalyptus wood fragments from different regions of brazil and to test their potential for degrading dead stumps and roots in eucalyptus plantings after harvest. fungi isolates were obtained in a culture medium composed by eucalyptus sawdust and agar. among 292 isolates submitted to the banvedamm test, 144 were classified as phenoloxidases producing isolates. among nine c/n ratios tested, it was observed a tendency of occurring larger chip decay in the c/n ratios equal to 60 : 1, 200 : 1 and 300 : 1. two decay assays were performed in wood chips of eucalyptus saligna using the c/n ratio 60 : 1 in order to verify which isolates were able to cause larger reduction of dry matter. in the first assay, which was evaluated at 90 days of incubation, seven isolates that stood out in relation to trametes versicolor were selected. the second assay evaluated the capacity of 46 isolates in promoting decay. the isolates selected in the first assay were among the 11 most efficient in the second assay. based on dna analysis, six isolates were identified as pycnoporus sanguineus (3 isolates), peniophora sp., pestalotiopsis sp. e ganoderma sp.
INFLUENCE OF LIQUEFIED AND CCB CONTAINING LIQUEFIED WOOD ON GROWTH OF WOOD DECAY FUNGI
Hrastnik,D; Budija,F; Humar,M; Petri?,M;
Maderas. Ciencia y tecnología , 2013,
Abstract: there are high amounts of post-consumed protected waste wood removed from service every year. the residual biocides, including copper, chromium and boron from ccb (cu, cr, b) in post-consumed wood that was protected with biocides may cause environmental problems during waste management, for example during land filling. therefore, the aim of this study was to find out if cu and cr in the processed waste wood, previously treated with ccb, can be re-used as a wood preservative or in coatings made of liquefied wood. liquefaction of ccb containing waste wood could be as well the first step in the elimination process of metals. so, the optimal conditions for liquefaction of ccb (cu, cr and b) containing black poplar (populus nigra l.) wood were established and compared with liquefaction of uncontaminated black poplar wood. the reactants for liquefaction of black poplar wood sawdust were ethylene glycol (eg) and sulphuric acid. it was observed that in the last stages of the liquefaction process, the presence of cu, cr and b did not have any influence on liquefaction yield (ly), while their influence was observed in first stages of the solvolytic reaction. investigations of fungicidal properties of uncontaminated and ccb containing liquefied wood showed higher antifungal efficacy of liquefied wood without cu, cr and b than of liquefied wood that contained ccb. in the tested concentration range, the presence of cu even promoted the growth of selected wood decay fungi. one of the reasons for higher toxicity of liquefied black poplar sawdust without cu, cr and b, was its very low ph value.
INFLUENCE OF LIQUEFIED AND CCB CONTAINING LIQUEFIED WOOD ON GROWTH OF WOOD DECAY FUNGI
D Hrastnik,F Budija,M Humar,M Petri?
MADERAS : Ciencia y Tecnología , 2013,
Abstract: There are high amounts of post-consumed protected waste wood removed from service every year. The residual biocides, including copper, chromium and boron from CCB (Cu, Cr, B) in post-consumed wood that was protected with biocides may cause environmental problems during waste management, for example during land filling. Therefore, the aim of this study was to find out if Cu and Cr in the processed waste wood, previously treated with CCB, can be re-used as a wood preservative or in coatings made of liquefied wood. Liquefaction of CCB containing waste wood could be as well the first step in the elimination process of metals. So, the optimal conditions for liquefaction of CCB (Cu, Cr and B) containing black poplar (Populus nigra L.) wood were established and compared with liquefaction of uncontaminated black poplar wood. The reactants for liquefaction of black poplar wood sawdust were ethylene glycol (EG) and sulphuric acid. It was observed that in the last stages of the liquefaction process, the presence of Cu, Cr and B did not have any influence on liquefaction yield (LY), while their influence was observed in first stages of the solvolytic reaction. Investigations of fungicidal properties of uncontaminated and CCB containing liquefied wood showed higher antifungal efficacy of liquefied wood without Cu, Cr and B than of liquefied wood that contained CCB. In the tested concentration range, the presence of Cu even promoted the growth of selected wood decay fungi. One of the reasons for higher toxicity of liquefied black poplar sawdust without Cu, Cr and B, was its very low pH value.
腐朽虫蛀木构件的耐久性预测模型研究进展
Review of the Prediction Model for Durability of Structural Wood under Decay and Termite Attack
 [PDF]

王小丽, 刘昊天, 王雪亮
Hans Journal of Civil Engineering (HJCE) , 2015, DOI: 10.12677/HJCE.2015.45026
Abstract: 对木结构进行剩余寿命预测需要从材料层面考虑木材的腐朽、虫蛀、干缩裂缝和持续荷载对木材长期抗力的影响。木构件腐朽深度的增大和木材强度的降低是腐朽引起木材长期抗力降低的主要原因,构件中的虫洞数量和虫洞深度减小了构件的有效横截面积是虫蛀对木材长期抗力降低的主要影响。因此,本文从木材腐朽和虫蛀的角度,分析总结了木构件耐久性预测模型研究进展,包括地面木构件腐蚀随时间变化的模型,与土壤接触的地面木构件的腐朽模型,地下木桩的腐蚀模型和虫蛀的可靠度模型等。并在此基础上,指出腐朽机理的研究,考虑各种环境因素建立更加合理的腐朽规律和虫蛀规律是有待解决的关键问题。
The mechanical properties of the structural wood are affected by its surrounding such as shrinkage cracks, decay fungi, termite attack and duration of load effect. It is necessary to study how these factors affect the resistance of the wood member during service life in order to predict the residual life of timber structure. Decay fungi induce the depth of decay increasing as time and the termite attack makes the wood have more pinholes. Both of them will greatly reduce the effective area of the wood member and meanwhile decay fungi decrease the strength properties in wood. In this paper the research development and achievement of the prediction model for durability of structural wood under decay and termite attack are reviewed in detail including decay model of in-ground timber, exposed timber in ground contact, above-ground exposed timber, protected timber and a reliability model under termite attack, and then it is concluded that it is the key problem and main future research to study on the mechanics of timber decay and to develop the quantitative prediction model under decay and termite attack considering various environmental factors.
Activité antifongique des huiles essentielles de Thymus bleicherianus Pomel et Thymus capitatus (L.) Hoffm. & Link contre les champignons de pourriture du bois d'oeuvre
El Ajjouri M.,Satrani B.,Ghanmi M.,Aafi A.
Biotechnologie, Agronomie, Société et Environnement , 2008,
Abstract: Antifungal activity of the Thymus bleicherianus Pomel and Thymus capitatus (L.) Hoffm. & Link essential oils againstwood-decay fungi. Essential oils and their constituents have a long history of applications as antimicrobial agents, but theiruse as wood preservatives has rarely been reported. This study deals with the antifungal activity of two medicinal and aromaticplants essential oils of the Moroccan flora against four wood-decay fungi, in order to find new bioactive natural products. Thechemical composition of essential oils extracted by hydrodistillation from the aerial parts of Thymus bleicherianus Pomel andThymus capitatus (L.) Hoffm. & Link was analyzed by GC and GC-MS. The major components of T. bleicherianus oil wereα-terpinene (42.2%) and thymol (23.9%). Carvacrol (70.92%) was the predominant constituent in the essence of T. capitatus.Minimal inhibitory concentrations of the essential oils added to malt agar medium in defined concentrations were determinedby a screening test with the agar dilution method. The oils, object of the survey, showed a strong antifungal activity againstall tested fungi.
Molecular techniques based on ITS analysis: useful tools for the identification of wood-decay Basidiomycetes in urban trees?
Robles,Carolina A.; Carmarán,Cecilia C.; Lopez,Silvia E.;
Kurtziana , 2012,
Abstract: the presence and identity of wood-decay basidiomycetes affecting platanus acerifolia were evaluated in buenos aires city during 2007. from 247 samples of basidiomes and wood with signs of decay, 19 strains were isolated, from which 10 rdna sequences were obtained. the aim of this work was to analyze the scope of information obtained from its sequences as taxonomic tools to study local populations of wood-rotting fungi in urban trees. phylogenetic analyses were performed under static and dynamic homologies. the techniques employed enable to: identificate coprinellus micaceus and corroborate the identification of bjerkandera adusta, while these same results were not achieved for inonotus rickii, ganoderma resinaceum, peniophora laxitexta and phlebiopsis gigantea due to the complexity of the genera and the lack of sequences. lack of sequences at a regional level would be a major obstacle for the detection of wood decay agents in urban trees using its sequences.
肉桂醛及其衍生物对木材腐朽菌和霉菌的抑制作用
杨冬梅,王慧,李淑君,袁海舰
- , 2017, DOI: 10.13360/j.issn.2096-1359.2017.01.009
Abstract: 天然存在的肉桂醛具有广谱的抗菌生物活性。为了开发环保、高效的木材防腐防霉剂,通过滤纸片法和处理材室内防腐防霉试验考察了肉桂醛及其3种衍生物对木材的防腐和防霉作用。滤纸片法实验结果表明,肉桂醛对4种供试菌种(即:密粘褶菌、彩绒革盖菌、黑曲霉和桔青霉)均表现出最强的抑菌性能。然而,在密粘褶菌对木材的腐朽试验中,对氯肉桂醛表现出最好的保护性能,在浓度为40 g/L时即达到Ⅰ级耐腐; 肉桂酸表现出优于肉桂醛的保护能力,在浓度为10 g/L时即达到Ⅱ级耐腐,而肉桂醛在20 g/L时方可达到Ⅱ级耐腐。在彩绒革盖菌对木材的腐朽试验中,肉桂醛和肉桂酸在浓度为50 g/L时达到Ⅰ级耐腐。在防霉方面,肉桂醛与对氯肉桂醛对黑曲霉和桔青霉有最好的防霉效果,特别是对于桔青霉,在浓度为68.67 g/L时完全防止了桔青霉的霉变。对于黑曲霉,在同样浓度下,两种化合物处理的木材试样都只是发生了很少的霉变。肉桂醛及其衍生物表现出对木材很好的保护作用,且环境友好,可广泛应用。
Cinnamaldehyde, which naturally exists in the world, has a broad-spectrum antifungal activity. In order to develop an environmentally friendly and effective preservative against wood decay and mould fungi, decay and mold resistant abilities of cinnamaldehyde and its three derivatives were examined by a filter paper disk method and wood block laboratory tests. The result of the filter paper disk method showed that among the four compounds, cinnamaldehyde presented the best antifungal activities against all the four selected fungi, i.e., Gloeophyllum trabeum, Trametes versicolor, Aspergillus niger and Penicillium citrinum. In the decay resistance experiment against Gloeophyllum trabeum, 4-chlorocinnamaldehyde showed the best performance and the treated wood could be ranked as Grade Ⅰ of wood decay resistance at the concentration of 40 g/L. Cinnamic acid presented better decay resistance than cinnamaldehyde, and the treated wood could be ranked as Grade Ⅱ of wood decay resistance at the concentration of 10 g/L. The treated wood could not be ranked as Grade Ⅱ until the cinnamaldehyde concentration was up to 20 g/L. In decay resistance experiments against Trametes versicolor, the wood treated with 50 g/L cinnamaldehyde or cinnamic acid could be ranked as Grade Ⅰ. As for mould resistance, cinnamaldehyde and 4-chlorocinnamaldehyde presented the best performance against Aspergillus niger and Penicillium citrinum, especially the latter mould fungous. Both cinnamaldehyde and 4-chlorocinnamaldehyde prevented the treated wood from the growth of Penicillium citrinum totally at a concentration of 68.67 g/L. As to Aspergillus niger,at the same concentration, both cinnamaldehyde and 4-chlorocinnamaldehyde presented good resistant abilities with little infected area. Cinnamaldehyde and the derivatives showed high decay and mold resistant abilities, and are environmentally friendly. Therefore, they have great application potential in wood preservation
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