• Applied Microscopy
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• v.29 no.3
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• pp.275-280
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• 1999

The genus of Hypoxylon, well known wood degrading fungi, is a member of the Xylariales, which has woody to carbonaceous, brown to dark brown stromata. Hypoxylon moriforme, which was isolated from heavily decayed hardwood, is fairly described by electron microscope. The isolation of H. moriforme will be the first record and the first description in Korea. The species collected, having small size of ascospores $7.5\sim9.0\times2.5\sim4.0{\mu}m$ and asci $75\sim130\times3\sim5{\mu}m$, are taxonomically compared with H. truncatum, which is well known as a popular species in Northeast Asia. And H. bovei and H. annulatum, which are the tropic to subtropic species and also compared with other temperate species of H. moriforme.

• Journal of the Korean Wood Science and Technology
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• v.44 no.5
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• pp.776-784
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• 2016

In this study, green Larix kaempferi lumber was heat-treated by using superheated steam (SHS) at a pilot scale and then various physico-mechanical properties of the heat-treated wood were evaluated and compared with the properties of conventional hot air (HA) heat-treated wood. Decay resistance of brown rot fungi and compressive strength parallel to the grain of the SHS heat-treated wood without occurrence of drying check from green lumber were increased. On the other hand, density, equilibrium moisture content, shrinkage, and bending strength of the SHS heat-treated wood were lower than those of the conventional HA heat-treated wood. Because heat transfer and thermal hydrolysis of SHS heat treatment was accelerated by a large amount of water, the effect of SHS heat treatment on the physico-mechanical properties was higher than that of HA heat treatment at the similar conditions of temperature and time. From the results of this study, because green lumber can be heat-treated without occurrence of cracks or checks by using SHS and similar heat treatment effect on the physico-mechanical properties of wood can be produced despite a low temperature or short time of heat treatment, it is expected that heat time and energy consumption could be reduced by using SHS.

• Journal of Life Science
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• v.19 no.10
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• pp.1389-1395
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• 2009

Generally, it takes a long time to purify wood vinegar, and it contains toxic compounds such as tar, methanol, phenol and benzopyrene. To reduce the toxicity of wood vinegar itself, we have developed a new purification method of wood vinegar using an oxidation-cohesion reaction and distillation with an active carbon. We have investigated the physico-chemical change (pH, specific gravity, refractive index and dissolved tar), the change of amount of toxic compounds (carbonyl group, phenol, benzopyrene and residual solvents) and organic acids (formic acid (FA), acetic acid (AA), propionic acid (PA)) of the purified wood vinegar under the long term and accelerated storage conditions. Also, we have evaluated the effect of the purified wood vinegar on hair growth using an alopecia model of C57BL/6 mice. As a result, we could find out that the purified wood vinegar was stable and remained without decay under the storage conditions and benzopyrene, a carcinogenic agent, was not detected in the purified wood vinegar. After topical treatment of the purified wood vinegar solution or minoxidil (MXD) for 2 weeks to dorsal skin, the hair regrowth of the mice accelerated faster than that of the control, with no clinical signs. In conclusion, we could suggest a guideline for quality control of process to reduce the toxic compounds in wood vinegar and it might be a useful hair growth promoter in the treatment of baldness or alopecia.

• Journal of the Korean Wood Science and Technology
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• v.38 no.6
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• pp.507-517
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• 2010

This study estimated the amount of carbon stocks in harvested wood products (HWP) using accounting approaches suggested by 2006 IPCC guidelines and analyzed the impacts of different approaches on national greenhouse gas inventory and the forest sector in Korea. The change in carbon stocks was calculated at the level of semi-finished wood products, which cover sawnwood, wood-based panels, other industrial wood, paper and paperboard. An estimation of the changes in carbon stocks in HWP in use for the period 1970~2008 varied between -9,023 Gg $CO_2$/yr and 4,052 Gg $CO_2$/yr depending on the accounting approach used. The stock-change approach provided the most favorable results because Korea was a net importer of wood products. However, each approach generates different impacts on harvest, trade, the use of wood for energy production and recycling. When deciding its position on accounting approach, thus, the Government should consider future direction of national forest policies as well as the effect on national greenhouse gas inventory for the minimization of negative impacts resulting from its selection.

• Journal of Conservation Science
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• v.23
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• pp.67-72
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• 2008

This study was conducted to examineboth the type of wood decay and the degree of degradation for the waterlogged woods (Alnus spp. and Fraxinus spp., about 5,700~5,900 year old), which were excavated at Higokri, Pyungteak in the west-coastal region of Korea. The transmission electron microscope (TEM) observation indicated the degradations by soft rot and bacteria were common in both woods. Erosion bacteria attacked gradually and irregularly from the secondary layer to compound middle lamella and often produced the cavity which was similar to soft-rot cavity but much smaller ones. Tunneling bacteria decomposed mainly $S_2$ layer. Though of highly degraded walls, the cells almost kept the original form with intact lignin-rich middle lamella, which were saturated by water. No marine borer's trace indicated that the sealine rise in the western coast of Korean peninsula during the climate optimum period in the holocene might not be high enough to submerge the Higokri area which locates about 2 km from the present sealine.

• Journal of the Korean Wood Science and Technology
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• v.15 no.2
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• pp.1-15
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• 1987

This experiment was undertaken for the purpose of investigation of relative durability about thirty sorts of the korean native wood and nine sorts of the wood destroying fungi Polystictus versicolor, Irpex consors. Poria vaporaria, Merulius lacrymans, Schizophyllum commune, Trametes pini, Lenzites betulina, Paxillus panuoides by means of a laboratory methods. The results obtained are; (from the table 2 to 10) 1. By measuring the percentage of loss in weight with regard to Polystictus versicolor, the sap wood contained in Junipeus chinesis was calculated at 18.2%, therefore it is much higher durability than any others and the sap wood contained in Pinus densiflora was measured at 44.10%, therefore it is much lower durability than any others. 2. By measuring the percentage of loss in weight with regard to Irpex consors, the heart wood contained in Butula schmidtii was calculated at 1.23%, therefore durability is very high and the heart wood contained in Quercus dentata was calculated at 26.79%, therefore durability is very low. 3. By measuring the percentage of lass in weight with regard to Lenzites betulina, the heart wood contained in Betula schmidtii was calculated at 5.33%, therefore it is much higher durability than any others and the sap wood with regard to Abies holophylla was measured at 45.48%, therefore durability is very low. 4. By measuring the percentage of loss in weight with regard to Poria vaporaria, the sap wood contained in Fraxinus rhynchophylla was calculated at 5.57%, therefore durability is very high and the sap wood contained in Paulownia coreana was calculated at 35.6%, therefore it is much lower durability than any others. 5. By measuring the percentage of loss in weight with regard to Merulius lacrymans, the heart wood contained in Castanea crenata was measured at 0.09% and in the next place, the heart wood contained in Abies holophylla calculated at 0.15% did not decay almost and the sap wood contained in Cornus controversa was measured at 32.88%, therefore it is lower durability than any others. 6. By measuring the percentage of loss in weight with regard to Schizophyllum commune, the sap wood cantained in Junipensis chinensis was calculated at 1.09%, therefore durability is very high and the sap wood contained in Populus deltoides was calculated at 36.87%, it is much lower durability than any others. 7. By measuring the percentage of loss ill weight with regard to Trametes pini, the sap wood contained in Robinia pseudo-acacia was calculated at 1.33%, therefore durability is very high and the sap wood contained in Comus controversa was calculated at 33.19%, it is much lower durability than any others. 8. By measuring the percentage of loss ill weight with regard to Paxillus panuoides. the heart wood contained in Zelkova serrata was calculated at 1.73%, therefore durability is very high and the sap wood contained in Populus deltoides was calculated at 42.30%, therefore durability in very low. 9. By measuring the percentage of loss in weight with regard to Dardalea quercina, the heart wood contained in Castanea crenata was calculated at 0.92%, therefore durability is very high and the sap wood contained in Cornus controversa was calculated at 32.00% therefore durability is very low. The above results are summarized as follows 1. Durability between the heart wood and the soft wood find that it is nonsignificant, while durability is higher heart wood than sap wood. 2. Special sorts including in the element like Castanea cenata, Robinia pseudo-acacia, Juniperus chinensis and heart wood like Betula schmiditii and Styrax obasia are highly durable and soft wood like Cornus controversa, Populus davidiana, Salix koreensis, Celtis jessensis are lowly durable in general. 3. Among the wood destroying fungi Paxillus panuoides is highly durable and as follows. Poria vaporaria, Lenzites betulina and the Daedalea quercina is less in general and Irpex consors, Mersulius lacrymans are a middle degree.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.798-803
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• 2015

This study was conducted to predict the effect of door opening in wooden cultural heritages (WCHs) on their conservation environment. For this prediction, measured relative humidity (RH) and surface wood moisture content (MC) of inner part of wood columns in open wooden building and neighboring closed wooden building were compared with minimum RH, including the duration of minimum RH, and MC required for spore germination and resultant growth of wood-degrading fungi reported in some literatures. Moisture conditions, namely RH of inside wooden building and MC of wood was unsuitable for decay and sap-stain fungi all the year round; however, moisture conditions during summer season was suitable for spore germination and resultant growth of surface mold fungi, regardless of door opening. When compared, the duration of minimum (75%) or higher RH and the number of wood columns with MC level greater than the minimum MC (15%) during summer season, the surface mold related to the conservation environment of inside wooden building was somewhat better in open building than in closed building. Rather, doors should be opened in closed building for reducing indoor RH as a necessary measure during summer season when outdoor RH is high.

• Journal of the Korean Wood Science and Technology
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• v.28 no.3
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• pp.52-61
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• 2000

Black locust(Robinia pseudoacacia) and poplar(Populus alba ${\times}$ glandulosa) trees were collected, extracted with acetone-$H_2O$(7:3, v/v) after drying, fractionated with hexane, chloroform and ethylacetate, and freeze dried to get some brown powder. Each fraction of the powder was chromatographed on a Sephadex LH-20 column using a series of aqueous methanol and ethanol-hexane mixture as eluting solvents. The wood extractives of black locust contained (+)-leucorobinetinidin as flavan, robtin as flavanone and dihydrorobinetin as flavanonol, and robinetin as flavonol. The poplar bark extractives contained various kinds of phenolic compounds : (+)-catechin as flavan, naringeoin, eriodictyol, sakuranetin, aromadendrin and taxifolin as flavanonol, salireposide as salicin derivative, and minor compounds such as aesculin and p-coumaric acid. However, aesculin has not been reported as a constituent of the poplar bark in Korea yet. NMR and FAB-MS analyses were done to elucidate the structures of isolated phenolic constituents.

• Korean Journal of Environmental Agriculture
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• v.25 no.3
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• pp.276-283
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• 2006

To evaluate the effectiveness of the foliar spray of calcium on "Baekdo" peach fruit, we carried out experiments in the orchards. The sprays were applied with $CaCl_2\;(Ca:\;400mg.kg^{-1})\;and\;CaCl_2$ with adjuvants (amino acid, $2g.kg^{-1}$; phytic acid, $2ml.kg^{-1}$ and wood vinegar, $2ml.kg^{-1}$) for four times from June 12 through July 4 at weekly intervals. The fruits and leaves were evaluated for Ca content, firmness and incidence of Brown rot caused by Monilinia fructicola at harvest To evaluate fruit quality included Ca content, firmness natural decay during the storage, the fruits were stored at room temperature for 14 days. The Ca content in leaf and fruit flesh at harvest was significantly increased (P=0.05) in $CaCl_2$ + amino acid treatment among $CaCl_2$ treatments. However, there was not significant Ca content in fruit peel. The firmness of flesh increased significantly (P=0.05) in $CaCl_2$ + amino acid treatment. The natural decay (Rhizopus stolonifers) during storage at the room temperature for 14 days, the fruit treated with $CaCl_2$ + wood vinegar exhibited lowest (P=0.05) incidence. Also, the firmness of the fruit during storage was firmer with treated $CaCl_2$ than untreated fruit. In the treatments of $CaCl_2$ + phytic acid and $CaCl_2$ + amino acid, it was possible to reduce incidence of Brown rot caused by M. fructicola most effectively in the field. In addition, inoculation with M. fructicola in fruits was also the most effective treatment for inhibiting disease development in vitro. These results suggested that the foliar spray of $CaCl_2$ with adjuvants increased the content of Ca and firmness of the fruits positively. It also inhibited the natural decay and the Brown rot effectively.

• Journal of Korean Society of Forest Science
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• v.98 no.1
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• pp.16-25
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• 2009

Cauliflower mushroom (Sparassis crispa) is recently recognized as a new edible and/or medicinal mushroom cultivated with conifers. By the way, the mushroom is notorious as a brown-rot fungus that causes a buttrot of larch. So, there should be a careful consideration to apply the mushroom cultivation in coniferous stand. This study was conducted to clarify the seriousness of heartwood decay on conifers such as larch by cauliflower mushroom with surveying the mushroom producing environment and to examine whether the cultivation of cauliflower mushroom produce any problem in conifer stands or not. The mushroom occurred in various coniferous stands such as Larix kaempferi, Pinus koraiensis, P. densiflora and Abies holophylla on fertile soils with adequate moisture. Soil texture of the mushroom producing site was comparatively fine compared to general forest soils; sandy loam, loam and silty loam. Soil pH ranged from 4.6 to 5.2, and organic matter contents were 4~11%, which showed relatively wide range. We could find S. crispa by a DNA technique from the wood that seemed to have no heartwood decay by naked eyes. The damaged wood showed 30% higher moisture contents than that of sound wood, while the compressive strength was 30% lowered down compared to that of sound wood. The fungus may invade conifers through the scars occurred on roots or stems, in this case spore dispersion of the mushroom takes a great role. Thus, we concluded that forest tending activities need to be applied with considering the invasion of S. crispa, and cultivation of cauliflower mushroom in forest should be attempted very carefully. By the way, we also infer that conifer stands can be nurtured without heartwood decay by S. crispa if the stand be managed in good aeration conditions by proper silvicultural practices such as sanitary thinning.