One of the most important biological factors that damage wood materials are wood-decay fungi (WDF). Chemical preservatives have traditionally been the most effective method for controlling WDF. ...However, due to environmental pressures, scientists are working on alternative protection methods. The aim of this study was to investigate the potential of some antagonistic fungi against wood-decay fungi as a biological control agent (BCA). For this purpose, the antagonistic effects of
Trichoderma harzianum, Trichoderma viride, Aspergillus niger
, and
Penicillium brevicompactum
fungi were investigated against the
Trametes versicolor, Trametes hirsuta, Stereum hirsutum, Coniophora puteana, Neolentinus lepideus
, and
Postia placenta
species of wood-decay Basidiomycetes fungi. In the study, firstly, inhibition rates were determined by comparing dual culture tests on agar medium, and then the performance of BCAs was compared by performing decay tests on wood blocks. As a result of the study, it was determined that the species belonging to the genus
Trichoderma
showed a very effective performance on WDF, increased the inhibition rate to 76–99%, and reduced the weight loss to 1.9–5.8%. Considering the inhibition rates, it was determined that the most effective rate of the BCAs was on
P. placenta
and the least on
S. hirsutum
species. According to the results obtained, it has been determined that some BCAs were very effective biological control agents of rot fungi on agar and wood blocks in vitro. However, in order to more clearly determine the effectiveness of BCAs in practice, this study, which was carried out in the laboratory environment, should be supported by tests performed in contact with the external field and soil.
•Photocatalytic nanotreatments were used to protect wood from Aspergillus niger.•Nanocoatings were aesthetically compatible with wooden artefacts.•Antifungal efficiency was established combining ...different quantitative parameters.•TiO2-based treatments partially restrained A. niger colonisation on wood surfaces.•The presence of metal nanoparticles did not greatly improve antifungal efficiency.
Fungi play a primary role in wood decay, including building and historical surfaces. Over the last years, nanotechnology has been used to preserve different type of surfaces from biodeterioration caused by the development of biological contaminants. In this study, photocatalytic titanium dioxide (TiO2) based nanocompounds (also containing silver and copper) were brushed on wood surfaces to evaluate biocidal ability against the development of soft-rot fungus Aspergillus niger. Five different nanotreatments were applied on two types of wood (softwood and hardwood). Compatibility with wooden substrates has been assessed using colorimetry. Antifungal capability of metallic nanotreatments was quantitatively evaluated considering different parameters: microscopic observation, chromatic variation, reflectance change and mould extent. Even though photocatalytic nanotreatments inhibited A. niger development only partially, they seem to be a promising tool to reduce harmful mould development and to better preserve wooden artefacts.
As a cutting-edge wood preservation technology, injection treatment to living trees has gained traction to prevent fungal infestation. Wood preservatives are injected into the lower part of the trunk ...and subsequently transported with xylem sap through transpiration. In this experiment, the waterborne wood preservative was synthesized by Ammoniacal Copper Quaternary (ACQ) and carbon dots (CDs), and its characteristics were determined. The distribution, loading capacity, and decay resistance of ACQ/CDs at different heights of the living poplar trees after the treatment were examined. Meanwhile, the effects of three methods, i.e. injection treatment, immersion treatment, and pressure treatment on the decay resistance and mechanical properties of the treated wood were explored. The results showed that the wood preservative penetrated well into the xylem after the injection treatment. The wood at different heights after the injection treatment had good decay resistance. The decay resistance diminished with the rise in tree height, attributable to variations in the timing of the preservative reaching different levels within the tree. When compared with the immersion and pressure treatments, the injection treatment can effectively reduce the influence of long-term preservative soaking and pressure application on the mechanical properties of the treated wood, while upholding commendable decay resistance.
RESUMO Os extratos vegetais podem ser uma alternativa sustentável no controle de agentes biodeterioradores da madeira diante de suas ricas fontes de químicos bioativos. O objetivo do estudo foi ...avaliar o desempenho de extratos naturais das folhas de Corymbia citriodora obtidos em diferentes metodologias de preparo, como alternativa para a preservação de madeiras de Eucalyptus sp. Seis tratamentos foram utilizados: T0 – testemunha, sem tratamento; T1 – CCB (Borato de Cobre Cromatado); T2 – Folhas maceradas manualmente e aquecidas a 100 °C; T3 – Folhas maceradas manualmente e imersas em água; T4 – Folhas trituradas mecanicamente e aquecidas a 100 °C; T5 – Folhas trituradas mecanicamente e imersas em água. A impregnação dos tratamentos na madeira de Eucalyptus sp foi realizada em bomba de vácuo e posteriormente os corpos de prova foram parcialmente soterrados em simuladores de campo com solo argiloso de pH 5 (Simulador 1); de textura média com pH 4,5 (Simulador 2); e arenoso com pH 5,1 (Simulador 3), onde permaneceram por 180 dias. Em seguida, foram realizadas as avaliações da perda de massa, desgaste visual, massa específica, ganho de massa, inchamento volumétrico e retenção da solução preservativa. As características do solo no simulador de campo não exerceram influência na perda de massa da madeira, independente do tratamento preservativo. Os valores de massa específica, ganho de massa, inchamento volumétrico e retenção da solução preservativa não apresentaram diferença estatística pelo teste de Tukey a 5% de significância. O Tratamento 1 apresentou resultados de perda de massa de apenas 2,27%. Já os materiais com extratos apresentaram variações: T2 – 7,86%, T3 – 9,93%, T4 – 8,47%, T5 – 18,84. Ao se comparar com os resultados do T0 – 18,83% observa-se que T2, T3 e T4 proporcionaram melhores propriedades contra o fungo da podridão mole. Sendo que a metodologia aplicada ao Tratamento 2 caracterizou-se como a mais promissora para as condições de preservação da madeira no campo.
ABSTRACT Plant extracts can be a sustainable alternative in the control of wood biodeteriorating agents due to their rich sources of bioactive chemicals. The objective of the study was to evaluate the performance of natural extracts from Corymbia citriodora obtained in different preparation methodologies, as an alternative for the preservation of Eucalyptus sp. Six treatments were used: T0 – control, without treatment; T1 – CCB (Chrome Copper Borate); T2 – Leaves macerated manually and heated to 100 °C; T3 – Leaves macerated manually and immersed in water; T4 – Leaves mechanically crushed and heated to 100 °C; T5 – Mechanically shredded leaves and immersed in water. The impregnation of the treatments in the wood of Eucalyptus sp was carried out in a vacuum pump and later the specimens were partially buried in field simulators with clayey soil of pH 5 (Simulator 1); medium texture with pH 4.5 (Simulator 2); and sandy with pH 5.1 (Simulator 3), where they remained for 180 days. Then, mass loss, visual wear, specific mass, mass gain, volumetric swelling and retention of the preservative solution were evaluated. Soil characteristics in the field simulator did not influence wood mass loss, regardless of preservative treatment. The values of specific mass, mass gain, volumetric swelling and retention of the preservative solution showed no statistical difference by Tukey’s test at 5% of significance. Treatment 1 presented results of mass loss of only 2.27%. The materials with extracts showed variations: T2 – 7.86%, T3 – 9.93%, T4 – 8.47%, T5 – 18.84. When comparing with the results of T0 – 18.83%, it is observed that T2, T3 and T4 provided better properties against the soft rot fungus. The methodology applied to Treatment 2 was characterized as the most promising for the conditions of wood preservation in the field.
•Perylene was found as a major compound in Mesozoic and Cenozoic fossil wood samples.•The high concentration and negative correlation with conifer biomarkers indicated extensive wood degradation by ...fungi.•A so-called conifer wood degradation index (CWDI) was defined.•Perylene carbon isotope values support its proposed origin from wood via wood-degrading fungi.
The occurrence of perylene in Middle Jurassic fossil wood and Miocene xylites from Poland is described, along with its correlation with unsubstituted polycyclic aromatic hydrocarbons (PAHs) as well as cellulose content. Both Middle Jurassic and Miocene wood remnants were of relatively low maturity ca. 0.2–0.3% vitrinite reflectance (Rr), had excellent preservation of biomarkers and biomolecules and, in the case of the Middle Jurassic fossil wood samples, generally good preservation of anatomical structures due to early diagenetic mineralisation. The results from 42 Middle Jurassic and 8 Miocene (most taxonomically defined) fossil wood fragments demonstrated a negative correlation between the concentration of perylene and those of generally typical conifer biomarkers (e.g. cadalene, dehydroabietane, simonellite and retene). In addition, good correlation (R2 0.81) was observed between the ratio of perylene to the above conifer biomarkers and the ratio of PAHs (phenanthrene and fluoranthene and pyrene) to the conifer biomarkers. This implies that the high concentration of perylene in fossil wood indicate its extensive degradation during decay, transport and early diagenesis. We defined a conifer wood degradation index as:
CWDI=perylene/(perylene+cadalene+retene+simonellite+dehydroabietane),
and observed a wide range of values (0.001 for less degraded wood to 0.95 for highly degraded samples). Anatomical wood preservation was associated with CWDI values. In most of the samples characterised by poorly preserved anatomy, high CWDI values were observed, while anatomically well-preserved samples generally had lower CWDI values. We determined similar δ13C values for perylene from the fossil wood samples (−26.4% to −27.8%), whereas the values for the conifer biomarkers were slightly higher and varied from −25.6% to −26.6%. In contrast, pyrene was depleted in 13C (−27.5% to −28.2%). The carbon isotope values of perylene are consistent with an origin from wood-degrading fungi.
Moisture content of wood has a pronounced effect on its physical and mechanical properties and also on susceptibility to fungal colonisation. For this reason, the information on distribution and ...concentration of water in wood is of a great importance. Large variability in wood structure and therefore distribution of moisture is expected among different tree species. The feasibility of magnetic resonance imaging for a non-destructive characterization of the moisture content and moisture distribution in tree tissues was tested and used in different applications, as for example in an in-vivo study of tree response to a mechanical wounding and in a study of efficacy of non-biocidal solutions for wood preservation (wax and oil based solutions).
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•Feasibility of MRI for a non-destructive moisture distribution in wood.•Method to determine the moisture content from MRI signal intensity.•Efficiency of MRI to study in vivo tree response to different stress conditions.•Efficiency of MRI in analyses of non-biocidal solutions for wood preservations.
Wood is the main material used for musical instrument soundboard fabrication, for practical and cultural reasons. As a natural material, however, wood is easily degraded due to moisture or fungal ...corrosion. Most traditional wood protection methods were devised for structural materials, and may thus not be suitable for application in musical instrument soundboard materials. In the current study, a novel nanomaterial-based modification method was applied to wood. The surface of wood was coated with polyurethane and MgAl-layered double hydroxide nanosheets after a convenient impregnation process. The modified wood exhibited improved hydrophobicity and mould-resistance, while maintaining its acoustic properties. This modified wood may facilitate the construction of soundboards with longer lifespans.
Wood deterioration due to basidiomycetous decay fungi shortens the useful life span of wood and wood-based materials. Prescriptive preservative treatment is the most effective way to reduce the ...detrimental effects of these microorganisms, particularly in soil contact and areas of critical use (difficult to replace or vital to structure). Current American Wood Protection Association (AWPA) guidelines in the standardized use category system specify 3 zones of severity regarding wood decay fungal hazards but contain very little information on the diversity and abundance of these fungi colonizing soil and wood. In this study, amplicon based sequencing was utilized to compare fungal communities in wood and adjacent soil to provide baseline data on the fungi involved in the process. A thorough understanding of decay hazards is critical for the proper selection and use of wood in soil contact. The goal of this work is to provide baseline data on basidiomycete fungal diversity and species composition in different zones of the existing 3-zone AWPA hazard map as compared to the previous 5-zone hazard map and Scheffer decay indices and discuss the ecological implications for wood decay.
Fouling of surfaces caused by pollution, contamination, humidity and microorganisms is one of the major sources of the degradation of mineral and composite materials. The inhibition of foulant growth ...is essential for the prevention of different kinds of damage, ranging from aesthetic, mechanical and chemical, to risks concerning human and environmental health. This study proposes a new approach for the development of a transparent preservative material with water-repellent and biocide attributes through the use of a sol-gel method. It was found that Si–O–Si dense networks can effectively grow into the micro-pores of mineral and cellulose-based materials, promoting self-cleaning properties as well as sufficient protection against bio-fouling.
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