Changes in chemical composition of decayed Scots pine and beech wood

AbstractIn this study, changes in chemical composition of aged and unaged Scots pine and beech wood decayed by brown-rot fungi Coniophora puteana and Poria placenta were presented by Fourier transform infrared (FT-IR) spectra. Samples were exposed to six complete cycles of accelerated aging for 12 days and then subjected to brown-rot fungi attack for 8 weeks. Weight loss of samples was found to be 25–46% depending on wood and fungi species and being aged ones. Accelerated aging treatments seemed to have a slight role on chemical composition of Scots pine and beech samples while they increased biodegradation of samples. FT-IR spectra showed degradation of wood carbohydrates revealed by reduction of the peaks responsible for hemicellulose and cellulose at 1730, 1370, 1150, and 897 cm-1 in pine and 1730, 1370, 1027, and 897 cm-1 in beech. Stronger lignin peaks at 1650, 1593, 1506, 1455, 1422, 1261, and 1230 cm-1 in pine and 1650, 1506, 1455, and 1422 cm-1 in beech were obtained after decay test. FT-IR spectra of samples were consistent with the degradation mechanism of brown-rot fungi. In general, changes in the carbohydrate and lignin peaks were greater in samples exposed to accelerated aging treatments for both wood species.

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Stilbene impregnation retards brown-rot decay of Scots pine sapwood

Holzforschung ◽

10.1515/hf-2014-0251 ◽

2016 ◽

Vol 70 (3) ◽

pp. 261-266 ◽

Cited By ~ 13

Author(s):

Jinrong Lu ◽

Martti Venäläinen ◽

Riitta Julkunen-Tiitto ◽

Anni M. Harju

Keyword(s):

Scots Pine ◽

Fungal Growth ◽

Brown Rot ◽

Monomethyl Ether ◽

Wood Preservation ◽

High Concentration ◽

Brown Rot Fungi ◽

Decay Test ◽

Antifungal Efficiency ◽

Brown Rot Decay

Abstract Stilbenes are abundant in the heartwood of Scots pine (Pinus sylvestris L.) and are known to have strong antifungal efficiency. In this study, Scots pine sapwood blocks were impregnated with crude heartwood extract containing the stilbenes pinosylvin (PS) and the pinosylvin monomethyl ether (PSM). Impregnated blocks were submitted to brown-rot fungi, Coniophora puteana, Gloeophyllum trabeum, and Rhodonia (Poria) placenta, and fungal growth test and decay test were performed. Both tests showed that the impregnation with a high concentration of stilbenes (60 mg g-1 dry wood) significantly suppressed the growth of fungi and slowed down the decay process of wood blocks, especially in case of G. trabeum. However, chemical analysis showed that PS and PSM were degraded by all the three types of fungi, obviously via modification to resveratrol and methylresveratrol. Rhodonia placenta displayed the fastest rate of degradation. Thus, impregnation with biodegradable stilbenes could be a viable alternative for wood preservation only in service situations with low or transient risk of decay.

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An FT-IR study of the changes in chemical composition of bamboo degraded by brown-rot fungi

International Biodeterioration & Biodegradation ◽

10.1016/j.ibiod.2013.05.029 ◽

2013 ◽

Vol 85 ◽

pp. 131-138 ◽

Cited By ~ 33

Author(s):

Eylem D. Tomak ◽

Elif Topaloglu ◽

Esat Gumuskaya ◽

Umit C. Yildiz ◽

Nurgul Ay

Keyword(s):

Chemical Composition ◽

Brown Rot ◽

Brown Rot Fungi ◽

Ft Ir ◽

Ir Study

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Decay resistance, extractive content, and water sorption capacity of Siberian larch (Larix sibirica Lebed.) heartwood timber

Holzforschung ◽

10.1515/hf.2006.017 ◽

2006 ◽

Vol 60 (1) ◽

pp. 99-103 ◽

Cited By ~ 13

Author(s):

Martti Venäläinen ◽

Anni M. Harju ◽

Nasko Terziev ◽

Tapio Laakso ◽

Pekka Saranpää

Keyword(s):

Siberian Larch ◽

Brown Rot ◽

Decay Resistance ◽

Extractive Content ◽

Strong Negative Correlation ◽

Average Mass ◽

Brown Rot Fungi ◽

Hygroscopic Properties ◽

Decay Test

Abstract The aim of this study was to find chemical or physical properties of Siberian larch heartwood timber that correlate with the variation in decay resistance. Juvenile heartwood from 24-year-old grafts of 15 clones was exposed to three brown-rot fungi according to the standard in vitro decay test (European standard EN 113). The mass losses caused by the brown rot fungi Coniophora puteana, Poria placenta, and Gloeophyllum trabeum were 20%, 28% and 17% of the dry mass, respectively. The average mass loss over the three fungi had a strong negative correlation with the concentration of taxifolin (r=–0.673, P=0.006), as well as with the concentration of total phenolics determined by the Folin-Ciocalteu assay (r=–0.677, P=0.006). Thus, the concentration of flavonoids is a promising property for indirect measurement of the decay resistance of Siberian larch timber. The most abundant heartwood extractives, arabinogalactans, had a non-significant relationship with the decay resistance, but their concentration correlated positively with the capacity of the wood to adsorb water (r=0.736, P=0.002). The hygroscopic properties of the wood or the wood density were not associated with the decay resistance.

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Efficacy of Caffeine Treatment for Wood Protection—Influence of Wood and Fungi Species

Polymers ◽

10.3390/polym13213758 ◽

2021 ◽

Vol 13 (21) ◽

pp. 3758

Author(s):

Miloš Pánek ◽

Vlastimil Borůvka ◽

Jana Nábělková ◽

Kristýna Šimůnková ◽

Aleš Zeidler ◽

...

Keyword(s):

Mechanical Properties ◽

Beech Wood ◽

Ecological Integrity ◽

Treated Wood ◽

Physical And Mechanical Properties ◽

Brown Rot ◽

European Beech ◽

Brown Rot Fungi ◽

Wood Protection ◽

Caffeine Treatment

In the future, we can expect increased requirements to the health and ecological integrity of biocides used for the protection of wood against bio-attacks, and it is therefore necessary to search for and thoroughly test new active substances. Caffeine has been shown to have biocidal efficacy against wood-destroying fungi, moulds and insects. The aim of the research was to determine whether the effectiveness of caffeine, as a fungicide of natural origin, is affected by a different type of treated wood. Norway spruce mature wood (Picea abies), Scots pine sapwood (Pinus sylvestris), and European beech wood (Fagus sylvatica) were tested in this work. The samples were treated using long-term dipping technology or coating (according to EN 152:2012) and then tested against selected wood-destroying brown rot fungi according to the standard EN 839:2015, wood-staining fungi according to EN 152:2012, and against mould growth according to EN 15457:2015. The penetration of caffeine solution into wood depth was also evaluated using liquid extraction chromatography, as well as the effect of the treatment used on selected physical and mechanical properties of wood. The test results showed that the type of wood used and the specific type of wood-degrading agent had a significant effect on the effectiveness of caffeine protection. The most resistant wood was the treated spruce, whereas the most susceptible to deterioration was the treated white pine and beech wood. The results of the work showed that caffeine treatment is effective against wood-destroying fungi at a concentration of 2%, and at 1% in some of the tested cases. It can be used as an ecologically acceptable short-term protection alternative against wood-staining fungi in lumber warehouses and is also partially effective against moulds. It also does not have negative effects on changes in the physical and mechanical properties of the tested wood species.

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Influence of carbon source on wood decay-associated gene expression in sequential hyphal zones of the brown rot fungus Gloeophyllum trabeum

Bioscience Biotechnology and Biochemistry ◽

10.1093/bbb/zbab080 ◽

2021 ◽

Author(s):

Kiwamu Umezawa ◽

Shuji Itakura

Keyword(s):

Gene Expression ◽

Gene Regulation ◽

Carbon Source ◽

Glycoside Hydrolase ◽

Degradation Mechanism ◽

Enzymatic Saccharification ◽

Brown Rot ◽

Gloeophyllum Trabeum ◽

Brown Rot Fungi ◽

Brown Rot Fungus

Abstract Brown rot fungi show a two-step wood degradation mechanism comprising oxidative radical-based and enzymatic saccharification systems. Recent studies have demonstrated that the brown rot fungus Rhodonia placenta expresses oxidoreductase genes ahead of glycoside hydrolase genes and spatially protects the saccharification enzymes from oxidative damage of the oxidoreductase reactions. This study aimed to assess the generality of the spatial gene regulation of these genes in other brown rot fungi and examine the effects of carbon source on the gene regulation. Gene expression analysis was performed on 14 oxidoreductase and glycoside hydrolase genes in the brown rot fungus Gloeophyllum trabeum, directionally grown on wood, sawdust-agar, and glucose-agar wafers. In G. trabeum, both oxidoreductase and glycoside hydrolase genes were expressed at higher levels in sections behind the wafers. The upregulation of glycoside hydrolase genes was significantly higher in woody substrates than in glucose, whereas the oxidoreductase gene expression was not affected by substrates.

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Influence of growth conditions on hydrophobicity ofLactobacillus acidophilusandBifidobacterium lactiscells and characteristics by FT-IR spectra

Spectroscopy An International Journal ◽

10.1155/2010/659167 ◽

2010 ◽

Vol 24 (3-4) ◽

pp. 251-255 ◽

Cited By ~ 9

Author(s):

Laisana Shakirova ◽

Lilija Auzina ◽

Peteris Zikmanis ◽

Marita Gavare ◽

Mara Grube

Keyword(s):

Chemical Composition ◽

Ir Spectra ◽

Physiological State ◽

Cell Surface Hydrophobicity ◽

Surface Hydrophobicity ◽

Growth Conditions ◽

Probiotic Properties ◽

Elevated Protein ◽

Ft Ir ◽

Quantitative Analyses

In this study we have found, that the values of cell surface hydrophobicity (CSH) ofL. acidophilusLA5 andB. lactisBb12 cells change in response to varied growth conditions – phase of growth, concentration or type of carbon source, presence of oxygen. An evaluation of FT-IR spectra using cluster and quantitative analyses revealed substantial changes of the chemical composition depending on the CSH level ofL. acidophilusLA5 andB. lactisBb12 cells. Decrease of the carbohydrate level was observed in proportion to the increased CSH values alongside with the elevated protein content of more hydrophobic cells of both cultures. The results of present study could help to specify the appropriate physiological state and environment forL. acidophilusLA5 andB. lactisBb12 to ensure their probiotic properties.

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Oil in Water Nanoemulsions Loaded with Tebuconazole for Populus Wood Protection against White- and Brown-Rot Fungi

Forests ◽

10.3390/f12091234 ◽

2021 ◽

Vol 12 (9) ◽

pp. 1234

Author(s):

Alejandro Lucia ◽

Mónica Murace ◽

Gastón Sartor ◽

Gabriel Keil ◽

Ricardo Cámera ◽

...

Keyword(s):

Beech Wood ◽

Brown Rot ◽

Vacuum System ◽

Diameter Distribution ◽

Hydrodynamic Diameter ◽

Promising Alternative ◽

Pycnoporus Sanguineus ◽

Brown Rot Fungi ◽

Wood Protection

Eugenol in water nanoemulsions loaded with tebuconazole appear as a very promising alternative formulations for wood protection against xylophagous fungi that are the main species responsible for different rots in wood structures. The dispersions as prepared and upon dilution (impregnation mixtures) were characterized by the apparent hydrodynamic diameter distribution of the oil droplets loaded with tebuconazole and their long-term stability. The impregnation mixtures were applied on wood of Populus canadensis I-214 clone by using a pressure-vacuum system, and the effectiveness against fungal degradation by Gloeophyllum sepiarium and Pycnoporus sanguineus fungi was determined. The retention of tebuconazole in wood was about 40% of the amount contained in the impregnation mixtures. The results showed that the impregnation process leads to a long-term antifungal protection to the wood, with the mass loss after 16 weeks being reduced more than 10 times in relation to the control (untreated poplar wood) and the reference wood (untreated beech wood).

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Fabrication of Chelate-Setting Cement Using Silicon-Substituted Hydroxyapatite and its Property

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.493-494.370 ◽

2011 ◽

Vol 493-494 ◽

pp. 370-374 ◽

Cited By ~ 1

Author(s):

Y. Nakashima ◽

Michiyo Honda ◽

Toshiisa Konishi ◽

Minori Mizumoto ◽

Mamoru Aizawa

Keyword(s):

Mechanical Property ◽

Compressive Strength ◽

Surface Modification ◽

Chemical Composition ◽

Ir Spectra ◽

High Dose ◽

Precipitation Reaction ◽

Ft Ir ◽

Xrd Patterns ◽

Surface Modified

We have developed novel hydroxyapatite (HAp) cement, “chelate-setting HAp cement” on the basis of chelate bonding of inositol hexaphosphate (IP6). In order to create the cement with enhanced bioactivity, we used a silicon-substituted hydroxyapatite (Si-HAp) as a starting material instead of pure HAp powder. The Si-HAp powders were prepared via an aqueous precipitation reaction and surface-modified with IP6 (IP6-Si-HAp). The Si-HAp were synthesized with desired Si contents (0, 0.4, 0.8, 1.6, and 2.4 mass%). Regardless of the amount of Si, the XRD patterns and FT-IR spectra of the powders were similar to each other. Additionally, chemical composition of Si-HAp powders were the almost same as the nominal one. The substitution of Si resulted in a decrease in the a-axis and increase in the c-axis of unit cell of HAp. While, the compressive strength of IP6-Si-HAp cements was higher than that of Si-HAp cements. These results suggest that surface-modification of any powders with IP6 is effective for enhancement of mechanical property. Comparison of mechanical property between HAp and Si-HAp cement specimens revealed that the substitution of lower levels of Si into0 HAp lattice did not greatly influence compressive strength. However, the substitution of high dose of Si (over 2.4 mass%) reduced the compressive strength. Therefore, to fabricate the chelate-setting cements with enhanced bioactivity, it is necessary to control the amount of Si.

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