• Journal of the Korean Wood Science and Technology
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• v.28 no.4
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• pp.10-16
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• 2000

Two wood decay ascomycetes fungi identified as Hypoxylon mammatum and H. truncatum were isolated from backyard of Korea Research Institute of Chemical Technology (KRICT) in Korea. Hypoxylon truncatum is newly recorded as a wood degrader in Korea. Unusual germination mechanisms of ascospores in H. mammatum and H. truncatum are described and illustrated. The differences between two species were noticed on the process of germ tube formation. In the process of germ tube formation, the fast movement to pigmented ascospores activated from their perispores was termed as spore eclosion that was only found in H. mammatum. This sophisticated recognition mechanism indicated the existence of specific eclosion and germ tube formation due to the composition of cell wall layers and their preferable host derive, based on examined two species under a genus. The observation on present study postulates different composition of wall layers of ascospore and different nutrient composition for germination.

• 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.24 no.1
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• pp.48-53
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• 1996

Brown rot fungus, Tyromyces palustris, has been reported to cause the loss of strength accelerated by oxalate, a non-enzymatic low molecular weight acid, with minute weight loss of decaying wood in early stage. The production of oxalate in relation to wood decaying and the presence of oxaloacetase. an oxalate producing enzyme, were identified during the process. Tyromyces palustris produced the largest amount of oxalate among brown rot fungi. In order to find out the cleavage of pulp fiber, we submerged pulp fiber in oxalate solution and the results showed that the number of short pulp fiber was highly increased, compared with control solution. The pH of decaying wood was decreased to 1.77 which was close to that of saturated oxalate solution, pH 1.2, Thus, the oxalate was thought to be accumulated in the decaying wood, The oxaloacetase which accelerates production of oxalate was derived from fungus, and the production of oxalate by the enzyme was determined by using on UV/Vis spectrophotometer. Therefore, the oxalate was found to be produced by oxaloacetase during decay. The oxalate may cause the acid-hydrolysis of cellulose and hemicellulose. The oxalate was thought to reduce the degree of polymerization and increase the enzyme activity, which resulted in rapid loss of strength in early stage-an identical feature of brown rot fungus.

• 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 the Korean Wood Science and Technology
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• v.30 no.2
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• pp.128-133
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• 2002

This study was conducted to investigate the influence of storage time on the sapstain development of Japanese red pine and Korean pine logs during storage in log yard, and their stain characteristics. Japanese red pine and Korean pine trees were harvested and cut into logs in mid January of 2001. These logs were transported to the two local sawmills where they were closely stacked in remote parts of log yard. The logs were then sampled destructively by cutting seven to nine 3-cm long discs along the length of each log at intervals of 3, 4, 5, 6, and 8 month after felling. The stain coverage and maximal radial penetration of stain were measured from the discs of the sampled logs after the isolation of causal staining fungi. The sapstain was primarily infested by the attack of bark beetles and the species of bark beetle was identified as Tomicus piniperda. The main fungal species isolated from stained wood was Ophiostoma species. Based on the present study, the logs could be stored in log yard until May without stain; but stain development was rapid after May and the severity of stain increased proportionally with storage time. Korean pine was more susceptible to fungal stain than Japanese red pine. During summer storage, decay started to develop in logs and the main species were identified as Tyromyces sp. and Schizophyllum commune. Information provided in this paper would be very useful to develop more effective control strategies for sapstain prevention in Japanese red pine and Korean pine logs.

• Applied Microscopy
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• v.37 no.4
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• pp.289-295
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• 2007

The genus Daldinia is a member of the Xylariaceae that has brown to dark brown and phaseoliform single cell ascospores with a conspicuous full germ slit. The isolate of D. childiae collected from Mt. Deuk-yu in Korea were compared with similar taxa, D. eschscholzii and D. concentrica.. Ascospores were $11{\sim}13{\mu}m{\times}5.5{\sim}6{\mu}m$ in size, light brown to brown, unicellular, ellipsoid-inequilateral, with dull round ends. Ascospore showed very faint ornamentation at ${\times}7.0k$ magnification. It is one of the main morphological characteristic Korean collection of D. childiae under SEM level and a main reason of reinterpretation of D. concentrica in Korea. Using KOH-extractable pigment color of stroma, D. concentrica that also has supported the SEM level investigation. Daldinia concentrica, having those characteristic recorded in Korea, should be renamed as D. childiae. However, the isolate will be the first record as D. childiae, having precise morphological description in Korea.

• The Korean Journal of Mycology
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• v.46 no.1
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• pp.43-50
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• 2018

Dadohaehaesang National Park is a well-known habitat for a variety of indigenous animals and plants; however, there are no studies on the diversity of macrofungi. To undertake a basic survey of the macrofungi diversity in an unexploited area, we focused on surveying the macrofungi in Dadohaehaesang National Park, Korea, during 2017 and discovered two unrecorded species belonging to the order Polyporales. The two species were identified as Cinereomyces lindbladii and Steccherinum bourdotii based on a combination of morphological characteristics and sequence analysis of the internal transcribed spacer region. We provide macro- and micro-morphological descriptions for these two unrecorded species in Korea.

• Journal of Korea Foresty Energy
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• v.22 no.2
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• pp.36-43
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• 2003

This study was carried out to evaluate the fungicidal, anti-sapstain and termiticidal efficacy of commercial Dan-Chung which are currently being used for painting to decorate and to provide durability with structures of temples. Two binders (Polysol and Gelatine), and eleven pigments (Iron Oxide Red, Lead Red, Toluidine Red, Chrome Yellow, Titanium Dioxide, Ultramarine Blue, Chrome Oxide Green, Permanent Black, Cyanine Green and Ho-bun(Chalk)) were applied for the evaluation. The fungicidal and anti-sapstain activity of each pigment were depended on the types of binders. When the Polysol was used as a binder, the fungicidal efficacy of Toluidine Red treated specimen was close to the standard value (above 80) with grater than 70 against to two wood decay fungi (T. palustris and T. versicolor). The anti-sapstain efficacy of Lead Red treated specimens was excellent against to three sapstain fungi (P. funiculosum, T. viride and R. nigricans), and that of Ultramarine Blue treated specimens was also excellent to T. viride. The other pigments had little efficacy to these micro-organisms. Although there were some different trends of the effectiveness depending on the types of binders, the anti-termite effectiveness of Chrome Oxide Green and Chrome Yellow was outstanding to termite tests.

• Journal of Korean Society of Forest Science
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• v.97 no.1
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• pp.35-44
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• 2008

Mycelial growth of Lentinula edodes on solid or liquid culture media supplemented with differentconcentrations of oak wood vinegar varied depending on the types of wood vinegar or mushroom varieties used.Oak wood vinegar obtained from traditionally carbonizing kiln (TWV) inhibited mycelial growth of L. edodes atthe dilution level of less than $5{\times}10^{-2}$, but stimulated at $10^{-3}$ to $2{\times}10^{-3}$. Wood vinegar from mechanicallycarbonizing kiln (MWV) inhibited at $10^{-3}$, but stimulated at $2{\times}10^{-3}$. In liquid culture media, both wood vinegarinhibited at $5{\times}10^{-2}$, but stimulated at $2{\times}10^{-3}$. Sanjo-302-ho grown in liquid culture media at $2{\times}10^{-3}$, and Sanrim 2and 3-ho grown at $4{\times}10^{-3}$ showed relatively high degree of wood decay (DWD) and growing ability within wood(GAWW) when these isolates were inoculated onto oak wood logs. TWV completely inhibited mycelial growth ofgreen mold fungi, Trichoderma species, tested at $5{\times}10^{-1}$ dilution level, while MWV inhibited at $5{\times}10^{-1}$ to $5{\times}10^{-2}$dilution level. For Diatrype stigma, TWV inhibited mycelial growth at the dilution level of less than $5{\times}10^{-2}$, whileMWV did 80% of mycelial growth at $10^{-2}$, and 100% at $5{\times}10^{-1}$ dilution level. Fresh and dry weight of fruitingbodies harvested after soaking of wood logs into wood vinegar solutions with different concentrations werecompared, and were the highest at $2.5{\times}10^{-2}$ dilution level. Storage test of fruiting bodies at $10^{\circ}C$ for 10 daysshowed that fruiting bodies harvested after soaking in the solution with $2.5{\times}10^{-2}$ dilution level showed the bestfreshness by general test and color changes. In addition, shear force value of L. edodes fruiting bodies measuredby using texture analyzer showed that $2.5{\times}10^{-2}$ dilution level was the best concentration for keeping flesh texture.

• Journal of Korea Foresty Energy
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• v.19 no.2
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• pp.93-101
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• 2000

Wood of Robinia pseudoacacia and bark of Populus alba$\times$P. glandulosa, Fraxinus rhynchophylla and Ulmus davidiana var. japonica were collected and extracted with acetone-water(7:3, v/v) in glass jar to examine whether its bioactive compounds exist. The concentrated extracts were fractionated with hexane, chloroform, ethylacetate and water, and then freeze-dried for column chromatography and bioactive tests. The isolated compounds were sakuranetin-5-O-$\beta$-D-glucopyranoside from Populus alba $\times$Pl glandulosa, 4--ethyoxy-(+)-leucorobinetinidin frm R. pseudoacacia and fraxetion from F. rhynchophylla and were characterized by $^1H$ and$^{13}C $ NMR and positive FAB-MS. Decay-resistant activity was expressed by weight loss ratio and hyphae growth inhibition in the wood dust agar medium inoculated wood rot fungi. R. pseudoacacia showed best anti-decaying property in both test and its methanol untreated samples, indicating higher activity than methanol treated samples in hyphae grwoth test. In antioxidative test, $\alpha$-tocopherol, one of natural antioxidants, and BHT, one of synthetic antioxidants, were used as references to cmpare with the antioxidant activities of the extacted fractions. Ethylacetate fraction of F. rhynchophylla bark indicated the hightest activity in this test and all fractions of R. pseudiacacia extractives also indicated higher activities compared with the other fractions. In the isolated compounds, aesculetin isolated from F. rhynchophylla bark showed best activity and followed by robonetinidin from R. pseudoacaica.