• Journal of the Korean Wood Science and Technology
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• v.24 no.3
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• pp.28-36
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• 1996

This experiment was carried out to elucidate the sugar composition of polysaccharides and the structural features of water-soluble polysaccharides(WSP) isolated from Korean oak mistletoe, Loranthus yadoriki Sieb. The 48-hours ball-milled meals of extractive-free dried mistletoe sawdusts were extracted with distilled water for $24hrs{\times}2$ at room temperature. The extracts poured into 95% ethyl alcohol to precipitate. The separated precipitate of WSP, in form of yellowish white powder by lyophilization, was fractionated into four subfractions of WSP-1, WSP-2, WSP-3 and WSP-4 by anion exchange chromatography on DEAE-cellulose column. The sugar composition of WSPs was analyzed by GLC in form of their glycitol acetates, and the structure of polysaccharides in Fractions WSP-1 and WSP-2 was determined by FT-IR and GC-MS after methylation through and acetylation. The sugars of WSPs from Korean oak mistletoe, Loranthus yadoriki, are majorly arabinose and galactose in stem, galactose in leaves very high in content and showed difference in composition and monomeric units between stems and leaves. D-galactose, D-glucose and L-arabinose are the simple sugars consisting of polysaccharides in WSP-1. ($1{\rightarrow}3$)-Linked galactan is the bakcbone with side chain of ($1{\rightarrow}5$)- -L-arabinofuranosyl residues and ($1{\rightarrow}6$)- -D-galactopyranosyl residues, and ($1{\rightarrow}4$)-linked glucan also presents. ($1{\rightarrow}4$)-Linked rhamnogalacturonan and ($1{\rightarrow}4$)- and ($1{\rightarrow}3$)-linked galactan present in WSP-2.

• Korean journal of applied entomology
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• v.49 no.2
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• pp.145-149
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• 2010

Differences in the number of Platypus koryoensis (Murayama) (Coleoptera: Platypodidae) trapped in different trap types, colors and positions on the trunk were evaluated to develop a monitoring trap for Platypus koryoensis, a known vector of Korean oak wilt disease. The experiments were conducted in an oak forest located in Gwangtan-myeon, Paju-si, Gyeonggi-do, Korea using two types of trap: sticky trap and multi-funnel trap. Trapping efficiency of the two trap types was not significantly different. Trapping efficiency of the sticky trap was not affected by four trap colors: yellow, black, white and transparent. The number of beetle caught was higher in the traps facing the upper slope than the lower slope regardress of trap type. Our results showed that both traps type are useful for monitoring Platypus koryoensis.

• Journal of the Korean Wood Science and Technology
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• v.16 no.3
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• pp.65-71
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• 1988

캐나다가 미국산 활엽수재의 가장 큰 수입국이며 수입된 일부 제재목과 수입원목으로 제조된 단판중 일부는 유럽으로 재 수출되고 있다. 수입 물량적인면에서 캐나다는 다른 국가와의 격차는 좁혀지더라도 미국산 활엽수재의 제1위 수입국의 위치를 당분간 유지할 것이다. 유럽에서의 제재목 수요가 1973년부터 1983년간의 10년간에는 급진적으로 증가 되었지만 1984년에 는 갑자기 감소되었다. 이와같은 현상은 과거 유럽 전통가구에 소재(素材)를 많이 사용했지만 현재는 소재(素材)를 적게 사용하고 단판이나 인쇄한 종이를 붙인 파아티클 보오드(PB)를 더욱 많이 사용하고 있기 때문이다. 현재 유럽지역에서는 가구의 크기를 줄이거나 가구에 사용되는 원자재의 비용을 줄임으로 제품의 가격을 싸게하여 소비자에게 보다 경쟁력있는 가격으로 제품을 공급할려고 하고 있으며 활엽수재의 가격이 너무 비싸 가구제조업체들은 소재(素材)를 다른 것으로 대체하고 보다 값싼 수종을 모든 지역에서 찾고 있는 중이다. 태평양 연안국가에서의 미국산 활엽수재의 수입 물량은 계속 증가되어 미국산 활엽수 총 수출 물량의 약 23% 정도 된다. 자유중국과 일본에서 미국산 활엽수재를 가장 많이 수입하고 있다. 자유중국은 주로 수출용 가구부품및 가구에 사용되는 red oak와 white oak 가 주 수종이고 가구는 미국으로 재 수출하고 있다. 일본은 주로 black cherry, yellow poplar와 cotton wood를 수입하는데 수입량의 약 67%는 대패질한 건조 가공품이다. 자유중국에서와는 달리 일본에서의 미국산 활엽수의 용도는 일본산 활엽수의 대체수종으로 허용되고 있다. 앞으로 일본에서의 미국산 활엽수재의 수요는 일본 국내시장의 요인에 의해 좌우될 것인데 한정된 물량의 일본산 활엽수재와 온대 활엽수재의 요구에 영향을 받을 것이다.

• The Korean Journal of Mycology
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• v.41 no.2
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• pp.85-90
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• 2013

This study investigated the internal and external morphological characteristics of decomposition and browning of oak sawdust medium for ground bed cultivation of Lentinula edodes. Within fifty days after L. edodes inoculation, surface hyphae on the bed browned. In 110 days, the fungal hyphae occupied and decomposed wood fibers, vessels and parenchymatous cells from the inside as white profuse hyphal mass was amorphously dissolving the saw dust particles from the outer surface. Most of the white hyphal bed surface became cleanly brown, however, some colony surface became blackened and slimy with contaminating bacteria, hyphae and spores. The brown layer was ca. 0.34 mm thick with highly dense and white hyphal mass beneath, whereas the blackened layer was ca. 1.17 mm thick with shrunken hyphae and less decomposed sawdust particles beneath. The surface hardness of the brown surface was ca. $0.73kgf/cm^2$, soft and resilient, while that of the blackened was ca. $0.91kgf/cm^2$, hard and nonresilient. By 150 days Lentinula edodes mushrooms fruited only on the brown surface and not on the blackened medium.

• The Korean Journal of Mycology
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• v.50 no.4
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• pp.291-300
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• 2022

In this study, the physical properties of the medium and changes in the wood chemical composition of the sawdust were investigated during the cultivation of oak mushroom sawdust bags, and the following results were obtained. After inoculation, the weight of the medium decreased during the incubation period. It is determined that this is not due to evaporation of moisture containing the medium or decomposition of sawdust, but to decomposition of rice bran, a low molecular substance added to the medium. It was confirmed that the moisture content of the medium was steadily increased during incubation, and it was estimated that the organic substrates such as rice brane in the medium was decomposed by mycelium, and water, one of the decomposition products of organic substrates, caused an increase in the moisture content of the medium. Along with the increase in the harvest of oak mushrooms, the proportion of organic substances such as holocellulose and lignin, the main components of the wood cell wall of sawdust, steadily decreased. In particular, the degradation characteristics of the wood cell wall component of shiitake, which is a white rot fungi, were confirmed by higher lignin reduction rate than that of holocellulose. On the other hand, ash, which is an inorganic material, increased with an increase in the number of mushroom harvests. The increase in the amount of ash in the medium may have been due to the decrease in the organic matter content such as holocellulose and lignin.

• Journal of the Korean Wood Science and Technology
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• v.33 no.2 s.130
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• pp.1-7
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• 2005

Tree species of wooden structural members of the Beomeo Temple were identified based on light and scanning electron microscopic characters in the present study. Of 10 structural members, 9 softwoods and 1 hardwood were identified. Among softwood members, 7 belonged to hard pine of the Sylvestris section, and the remaining 2 to hard pine of other than the Sylvestris section and hemlock of the genus Tsuga, respectively. A single hardwood member was identified as white oak of the Prinus section under the subgenus Lepidobalanus.

• Journal of the Korean Wood Science and Technology
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• v.17 no.3
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• pp.52-60
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• 1989

This study was carried out to know the possibility of simultaneous utilization of laccase from white-rot fungus with cellulase on enzymatic hydrolysis of cellulosic substrate from autohydrolyzed oak wood. Laccases from 3 white-rot fungi, Pleurotus ostreatus. Ganoderma lucidum, and Phanerochaete chrysosporium, were isolated, purified and measured their activities. The highest activity was shown in Pleurotus ostreatus and the lowest in Phanerochaete chrysosporium. Laccase from Pleurotus ostreatus has optimum pH of 5.94, Km value of 3.209 mM and appeared to be stable at relatively wide pH range, 4.7-8.72. Temperature stability showed that 60% activity was preserved after 40 minutes at $50^{\circ}C$. Laccase from Ganoderma lucidum reached to the maximum activity during 15-20 day incubation. This enzyme has optimum pH of 6.45, Km value of 6.71 mM and pH range of 5.0-9.0 for stabilization. 95% activity was preserved at $30^{\circ}C$ and 58% activity at $50^{\circ}C$. Concerned to the enzymatic hydrolysis of cellulosic substrate with both enzymes, cellulase and laccase, simultaneously, mixed culture filtrates and mycellium extracts were shown higher hydrolysis rates than those of Trichoderma viride. There were no significant differences in the extent of hydrolysis among various mixed culture filtrates and mycellium extracts.

• The Plant Pathology Journal
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• v.19 no.2
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• pp.79-84
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• 2003

Sclerotinia rot occurred severely on some vegetable crops grown in Namyangju, Yangpyung, and Yangiu areas in Korea in 2001-2002. The crops infected with Scterotinia sp. were Adenophora remotiflora, Armoracia lapathfolia, Angelica acutiloba, Angelica archangelica, Anthriscus sylvestris, Aster tataricus, Beta vulgaris var. cicla, Brassica campestris var. marinosa, Brassica juncea var. laciniata, Chicholium intybus, Lactuca indica var. dracoglossa, Lactuca sativa var. oak-leaf, Petroselinum crispum, and Phyteuma japonicum. The fungus associated with the disease was identified as Sclerotinia sclerotiorum, based on the morphological characteristics of the pathogen. The symptoms were water-soaked spots that enlarged later and became a watery soft rot. Infected parts became yellow and then turned brown, followed by death of the whole plant. White mycelia developed on the upper petioles and leaves and on the soil where these plant parts lay. Then black sclerotia in variable size and shape formed from the mycelial mass. Pathogenicity of the fungus was proven by artificially inoculating each crop. This is the first report of Sclerotinia rot on the listed vegetable crops in Korea.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.1
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• pp.63-72
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• 2009

The experiment was conducted from 2007 to 2008. The experimental roughages include five sources and 25 species in all; grasses and legumes: 5 species (mixed grasses, orchardgrass, tall fescue, alfalfa, white clover), native grasses and weeds: 5 species (mixed native grasses, Miscanthus sinensis Anderss, Arundinella hirta (Thunb.) Tanaka, barnyard grass, short awn, forage crops and straw: 5 species (barley 4- hairy vetch, wheat 4- hairy vetch, rye silage, barley silage, baled rice straw), browse and fallen leaves: 5 species (mixed browse, oriental white oak browse, Quercus serrta Thunb., browse oriental cherry fallen leaves, Japanese chestnut fallen leaves), and imported hay and straw: 5 species (timothy hay, tail fescue straw, annual ryegrass straw, klinegrass hay, alfalfa hay). Ten dairy goats (Saanen) were selected which had nearly the same body weight (25kg). The experiment was carried out on the dairy goats farm at Geumsan-Cun in Chungnam province. The chemical composition and dry matter digestibility of each roughage source and species were significantly different at the sampling area, plant species, growth stages and cutting period. Among all the 25 species of roughages, the favorite intake species order by dairy goats was observed like this: mixed grasses, white clover, alfalfa and the lower intake species order was baled rice straw and rye silages. The dairy goats ate more roughages which had low fibrous contents, but high dry matter digestibility. On the other hand, compared to each roughage source, the goat's favorite roughage were grasses and legumes (34.6%) among the trial species. Based on the result, it is reconfirmed that the food habit of dairy goats seems to be closer to that of graters.

• Mycobiology
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• v.38 no.1
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• pp.7-12
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• 2010

A green mold species that has not previously been reported in Korea was isolated from oak log beds used for shiitake (Lentinula edodes) cultivation that were infested by mushroom flies. In this study, we identify the mold species as Gliocladium viride (an anamorph of Hypocrea lutea) and describe its mycological properties. The fungus was cottony on both potato dextrose agar (PDA) and Czapek yeast extract agar (CYA), but was colored white on PDA and became yellowish green and brown on CYA. Mycelial growth on PDA attained a diameter of 73 mm at $30^{\circ}C$ after 5 days. The fungus grew faster on malt extract agar (> 80 mm, 5 days at $25^{\circ}C$) compared to CYA and PDA (< 68 mm, 5 days at $25^{\circ}C$). Penicillate conidiophores of the fungus are hyaline, smooth walled, branching above typically in four stages, and $120\sim240\;{\mu}m$ in length. Club-shaped or slender phialides are formed on the metulae. Conidia of the fungus were ovate and elliptic, yellowish brown and green, and $2.5\sim3.0\;{\mu}m\times1.8\sim2.3\;{\mu}m$ in size. Typically, slimy conidia are formed in a mass and colored brown to dark green to almost black. The internal transcribed spacer rDNA and translation elongation factor 1 alpha gene sequences of the fungus isolated here show 99% identity with previously identified G. viride strains.