• 보존과학연구
• /
• s.33
• /
• pp.99-108
• /
• 2012

The white-rot fungus (Trametes versicolor) and brown-rot fungus (Tyromyces palustris), which cause damage to a variety of wooden cultural properties and buildings, such as drying of the wood tissue, decay and cracks, sponge, and discoloration, give rise to serious structural and aesthetic problems. Moreover, pest termites (Reticulitermes speratus kyushuensis Morimoto) can cause damages like hollowing the outdoor beams or pillars of wooden buildings and finally causing such buildings to collapse due to the termites' destruction of the inside of the beams or pillars, leaving only a thin layer on their surfaces. This study was conducted to determine the impact of the wood-decay fungus, a representative damage-causing microorganism, and of insects and termites on the termite ecology. The damage ratio was calculated as the weight of the timber, and the overall total mass was reduced from two kinds of rot fungi. The white-rot fungi reduced the total wood mass, but the brown-rot fungi were observed to have had an increasing tendency to do so. The wood mass was measured after drying to determine the destruction capacity of termites. As a result, the wood mass consumed by the brown-rot fungi was shown to be greater.

• Journal of the Korean Wood Science and Technology
• /
• v.31 no.1
• /
• pp.1-9
• /
• 2003

Antimicrobial activities of plant extractives were investigated to develop a natural fungicide. Two stilbenoids and five flavonoids were isolated from wood extractives of Hovenia dulcis (Rhamnaceae) which had been selected due to its high antifungal activity among the tested species. The chemical structures of isolated compounds were determinded as : 5-hydroxy-7-methoxyflavone, 5,7-dihydroxyflavone (chrysin), 5,7-dihydroxyflavanone (pinocembrin), 3,5,7-trihydroxyflavanone (pinobanksin), 3,4',5,7-tetrahydroxyflavanone (aromadendrin), 3-hydroxy-5-methoxystilbene and 3,5-dihydroxystilbene (pinosylvin) on the basis of Mass and NMR spectroscopic data. According to the results of antifungal test, 3-hydroxy-5-methoxystilbene was evaluated as the strongest antifungal compound among the tested compounds and next were pinocembrin and pinosylvin, but those also had high hyphal growth inhibition activities against C. parasitica, T. versicolor, T. palustris and T. viride. However, pinobanksin, 5-hydroxy-7-methoxyflavone, chrysin and aromadendrin showed very low antifungal activity. In this regard, it could inferred that high antifungal activity of wood extractives of H. dulcis were derived from 3-hydroxy-5-methoxystilbene, pinocembrin and pinosylvin, respectively.

• 보존과학연구
• /
• s.31
• /
• pp.89-102
• /
• 2010

This study evaluated the activity of biocidal compounds isolated from natural products and confirmed applicable possibility as conservative agents for orgainic cultural heritages damaged by biological degradation. we used methanol extracts of 11 Korean trees and 17 medicinal plants as natural resources. Among these extracts, Phellodendron amurense was investigated on antifungal activity against Coniophora puteana, Lentinus lepideus, Tyromyces palustris and Aspergillus niger. Asarum sieboldii was investigated on insecticidal activity against adult of Lasioderma serricorne. First, the extract of Phellodendron amurense was partitioned into hexane, dichloromethan and ethylacetate fraction. Among them, the ethylacetate fraction had the most significant antifungal activity. In addition, Asarum sieboldii essential oil showed an effective antifungal and insecticidal activity. As a result, the extract of Phellodendron amurense and Asarum sieboldii essential oil could be useful for conservation of organic cultural heritage against biological deterioration by wood rot fungi and Lasioderma serricorne.

• Journal of the Korean Wood Science and Technology
• /
• v.23 no.2
• /
• pp.77-82
• /
• 1995

With the aim to utilize pine wood(Pinus densiflora Sieb. et Zucc.) as an interior building materials, such as flooring material, monoethylene glycol(MEG) resin solution was impregnated into greenwood. Specimens of three different qualities, that is, normal wood, resinous wood and compression wood, were prepared. Distribution of resin element(phosphorus) in MEG resin solution-impregnated woods and preservative effectiveness against brown rot fungi(Tyromyces palustris and Serpula lacrymans) of these woods were investigated. The results were as follows: 1. The concentration of phosphorus into cell walls of resinous wood and compression wood was lower compared to that of normal wood. This shows that the quality of wood has an influence on the penetration of MEG resin solution into the wood. It was shown from a leaching test that MEG resin could be leached out easily from the cell walls. 2. The resinous wood and compression wood, even without MEG resin solution impregnation had high decay resistance. For normal wood, significant improvement of preservative effectiveness was observed after impregnation of MEG resin solution. It was shown that MEG resin was leached out from the woods after leaching test, resulting in the reduction of preservative effectiveness. From this result, suitability of MEG resin solution-impregnated woods as an interior materials was recognized.

• Korean Journal of Agricultural Science
• /
• v.22 no.1
• /
• pp.42-48
• /
• 1995

With the aim to investigation of decay resistance and optimum concentration in chrome-copper-arsenic(CCA) preservative treatment on the imported softwoods from Siberia and North america, preservative absorption after CCA impregnation, weight losses and degradation patterns by decay fungi were examined. The density and latewood rate of Siberia softwoods(Spruce and Larch) were higher than those of North america softwoods(Douglas-fir and Western hemlock), resulting in the decrease of the CCA preservative absorption in the Siberia softwoods. In the case of untreated softwoods, decay resistance against Coriolus versicolor was lower than against Tyromyces palustris. For CCA treated softwoods, preservative effectiveness increased with increase in concentration of CCA solution. When treated with 0.7% CCA solution, efficiency value was more than 80 and 90 for C. versicolor and T. palustris, respectively. From this results, in the CCA preservative treatment for imported softwoods, it can be concluded that optimum concentration of CCA solution is approximately 0.7%. The absorption of CCA preservative distributed in the range of 3.8 and $5.5kg/m^3$. After exposure to testing fungi, in the untreated softwoods, bore holes formed in the cell walls and bordered pits, moreover, bordered pit canals enlarged by the fungi. However, 0.5% CCA treated softwoods was almost no deterioration in the cell walls and bordered pits due to decay.

• Journal of the Korean Wood Science and Technology
• /
• v.32 no.2
• /
• pp.50-57
• /
• 2004

This study attempted to evaluate the water repellency and drying effectiveness of linseed oil treated-solid wood at high temperature by immersion. The moisture content of green wood (Pinus densiflora) sample (above 90%) was reduced about 10% after 6 hours treatment at 150℃. When the treated samples were cut into cross section along the length, it was observed that the linseed oil penetrated into up to 20% of the sample cross section area in all locations. However, a strength loss of the specimen was not detected. The pre-drilling before linseed oil treatment was effective in reducing the defects such as checks and splits, and improved the linseed oil penetration into all samples from the surfaces. The result of water absorption test of treated-wood showed that the water repellent efficacy of treated-wood was greater than that of the control. The anti-fungal activity of treated samples using five sap stains and thee decay fungi was not detected in broad-spectrum toxic mechanism. However, decay test using white rot fungi (Tyromyces palustris) and brown rot fungi (Trametes versicolor) showed that the treated sample has a decay resistance to these two fungi.

• Journal of the Korean Wood Science and Technology
• /
• v.30 no.1
• /
• pp.48-55
• /
• 2002

The essential oils were extracted from the needles of several softwood tree species, Pinus densiflora, Pinus koraiensis, Chamaecyparis obtusa and Chamaecyparis pisifera to investigate their biological activities. The antifungal activity by hyphal growth inhibition method was determined by three wood rot fungi, one mouldous fungi, and three tree pathogenic fungi and the antibacterial activity by paper disc method and turbidiometric method by three gram positive bacteria and one gram negative bacteria, Escherichia coli, were also tested. Antifungal activity was the best in the essential oil from C. obtusa, and the following was resulted in order of P. densiflora and P. koraiensis. The essential oil from P. densiflora showed higher antifungal activity against wood rot fungi than that from P. koraiensis while the result was contrary against tree pathogenic fungi. However, the antibacterial activity was the best in the essential oil from P. densiflora, and the following was in order of C. obtusa and P. koraiensis. From these results, the variation of biological activity seemed to be due to the chemical composition of essential oils.

• Economic and Environmental Geology
• /
• v.56 no.6
• /
• pp.899-909
• /
• 2023

In this study, the material scientific characteristics of Hobun pigments used as white inorganic pigment for traditional cultural heritage were identified according to the type of shell and calcination and evaluated the stability of the preservation environment. For the purpose of this, we collected 2 different types of Hobun pigments made by oyster and clam shell and its calcined products(at 1,150℃). Hobun pigments before calcined identified calcium carbonate such as calcite, aragonite but calcination derived changing main composition to portlandite and calcite. Results of FE-SEM showed characteristics microstructure for each shell but pigments after calcined observed porous structure. Porous granule highly caused oil adsorption according to increase specific surface area of pigments. In addition, the whiteness improved after calcined pigments compared to non-calcined pigments, and the color improvement rate of Hobun pigment (CS) which made of clam shell was higher. As a result of the accelerated weathering test, the Hobun pigment-colored specimen had a color difference value of less than 2 after the test, which was difficult to recognize with the naked eye. In particular, the color stability has improved as the color difference value of the Hobun pigment is smaller after calcined compared to before non-calcined pigment. However, it was confirmed that the stability of the painting layer was lower in the specimen after calcined pigment. For antifungal activity test, Aspergillus niger, Tyromyces palustris and Trametes versicolor were used as test fungi, and all pigments were found to have preventive and protective effects against fungi. Especially, the antifungal effect of the calcined pigment was excellent, which is due to the stronger basicity of the pigment.