• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.39-41
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• 2003

Pollen and spores as well as their morphological characteristics are biological stability materials in which contains historical information about vegetation and climate changes. As noted researcher Neishtadt in 1971, the lake and swamp deposits were developed only in Holocene period. The geological history of Darkhad depression which is situated in the Northern end of Mongolia from ancient time become under scientific interest of many researchers. Our investigation was focused on pollen analysis of lake sediment of Darkhad depression which caused bottom of paleolake. In Mongolia the palynology science is beginning to develop since 1990 and in 2000 the laboratory of palynology was established at the department of Biology, State Pedagogical University of Mongolia. Researchers from this laboratory working on pollen morphology of present flora in order to classify plants taxonomy. Another part of our investigation is mellitopalynology, which is studying of pollen grains in a honey. Although, this research has been extending by pollen analysis of sediment and lake deposits in past few years on the basis of high sensitive microscope and modem technology.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.1
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• pp.23-30
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• 2018

Kudoa septempunctata, a myxosporean parasite that infects olive flounder Paralichthys olivaceus is known to cause Kudoa food poisoning. Entire trunk muscle (ETM) is used for diagnosis of the parasite in fish and this method demands sacrifice of the host, causing a loss of commercial value. We developed a non-destructive method that uses a plastic syringe-style implanter to draw the sample, called the part-point muscle (PPM) sampling technique. We validated the PPM method in fish infected with K. septempunctata at the level detectable by the ETM method. We confirmed that the PPM method is equally sensitive in comparison to the ETM method for diagnosing K. septempunctata spores in olive flounder muscle. Our study also confirmed that the parasite is uniformly distributed in the dorsal muscle of infected fish. Over a period of 1 month, we observed no mortality of the host fish used for sampling by the PPM method. Thus, our studies demonstrate that the PPM sampling technique is an efficient, non-destructive method for diagnosing K. septempunctata in olive flounder.

• Korean Journal of Microbiology
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• v.43 no.1
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• pp.59-65
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• 2007

The optimal conditions for Monascus pigments production of Monascus sp. KM 1001, pigment overproducing mutant, in submerged culture was investigated. The optimal medium for the production of pigment from KM 1001 mutant is determined to be composed of 4% rice powder, 0.15% Bacto-peptone, 0.1% glycine, 0.01% $FeSO_{4}{\cdot}7H_{2}O,\;0.1%\;MgSO_{4}{\cdot}7H_{2}O,\;0.25%\;KH_{2}PO_{4},\;pH4.5$. On optimal conditions,10.0 g/L of the cell mass was obtained at $30^{\circ}C$ for 5 days. Yellow, orange and red pigment of Monascus sp. KM 1001 were produced 3.25 units, 1.59 units and 0.88 units in extracellular part, and 84.96 units, 78.84 units and 91.80 units in intracellular part, respectively.

• Current Research on Agriculture and Life Sciences
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• v.1
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• pp.67-83
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• 1983

The new microsporidia S80 isolated from, Bombyx mori L. in Korea showed ovoid in the morphology of the spores and the size were measured $2.9{\pm}0.28{\mu}$ in length and $1.7{\pm}0.29{\mu}$ width. No other microsporidian spore like this has not been so far isolated from Silkworm. The length of the polar filament extruded in hydrogen peroxide ($H_2O_2$) at $30^{\circ}C$ was $26{\mu}$ of a round cytoplasm on the top. The spores were partly stained with Giemsa, Safranin-O and Gram as the same staining properties as Nosema bombycis, Microsporidia K 79 and other microsporidian spores. The fine structures were observed under scanning eleceron microscope through ultrathin sectioning. The spore wall was composed of three layers ; the thin exospore of an electron dense rippled layer, the thick electron lucent endospore which was thinning considerably at the polar filament insertion point, and the inner limiting membrane. Polar cap present at the sporeapex, with a long polar filament of 12-13 coils, subtending angle of $60^{\circ}$ to spore axis, which is tubular made up of a multilayered and are a benes core, light ring structure enclosing the dance core, the dark ring structure enclosing the inner light ring structure and the other than and light ring structure bounded from cytoplasm. Lamellate polaroplast occupied the anterior part of the spore, and the two neclei with dense nucleoplasm bounded by a double nuclear envelope were cited in the slight downer middle portion of spore. From the characteristics of the shape, size and fine structures, it is certain to reason the Microsporidia S80 belong to the phylum Microspora, class Microspora, order Microsporida, order Microsporida. The shape of two nuclei cited seems to be genus Nosema, but in the classification for the suborder it should be defined wheather pansporoblasts be formed or not and for the genis especial attempts have been made to define the characters which distinguish the disporous genera in the life cycle. Survey through the infection of the bad cocoons during 1980 to 1982 in South Korea the areas contaminated with new microsporidia were revealed 5 provinces of Kyung-Gi, Kang-Won, Chung-Nam and Chun-Nam. Pathological effects inoculated per os at second instar larvae of silkworm, the LD 50 was $7.1{\times}10^7/ml$ as lower pathogenecity than that of Nosema bombycis Naegeli of $1.2{\times}10_7/ml$. While on the other hand the inoculation of the microsporidia at fourth instar larvae lowerd the whole cocoon weight and cocoon shell weight and significant at 1% level. The microsporidia S80 defined it can not be transmitted transovarially from the result of predictive and collective examination of 21 egg batches from the infected female moth.

• The Korean Journal of Mycology
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• v.32 no.2
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• pp.79-88
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• 2004

Cordyceps pruinosa grows upon dead pupae of Lepidoptera and produces one or $3{\sim}4$ club-shaped stromata per host. The stromata have distinct club-shaped head and long stalk. The length of stromata varies from $1{\sim}3\;cm$. Apical head consists of densely crowded semi-immersed perithecia, which are $360{\sim}400\;{\times}\;180{\sim}200\;{\mu}m$ in size. Asci are $150\;{\mu}m$ in length and $2.8{\sim}3\;{\mu}m$ in diameter. Ascospores, which are $124{\sim}141\;{\mu}m$ in length, have thin thread-like structures in the middle with part-spores attached on both sides. Each ascospore does not separate into part-spores after dispersal, but each part-spore germinates and together develops a colony. The imperfect form produces phialides of $15{\sim}24\;{\times}\;2{\sim}3\;{\mu}m$ size, with spherical or spindle shaped conidia of $4{\sim}6\;{\times}\;1.8{\sim}2.4\;{\mu}m$ size, The anamorph was identified as Mariannaea elegans Samson. YMA and SDAY agar media with pH 7 was produced abundant mycelial growth with high density. Best mycelial growth was observed when dextrin was used as a carbon source. Lactose, saccharose and sucrose also produced high mycelial growth. Peptone, yeast extract and tryptone produced abundant mycelial growth, when used as nitrogen sources. Highest mycelial growth and density was observed when C/N ratio was 1 : 1 at the concentration of 12.5 g/l each. $KH_2PO_4$ was the best mineral source for mycelial growth. Highest mycelial dry wt. was produced in YM and SDAY broths. Optimum inoculum for 100 ml of liquid broth was 6 mycelial discs. Similarly, optimum liquid culture period was 7 days.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.3
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• pp.325-331
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• 2012

The dual inoculation response of soybean with rhizobium and mycorrhiza was examined in pot vermiculite and field soils. In order to select a symbiotically compatible mycorrhiza with Bradyrhizobium japonicum, a highly germinating spore among 60 strains from 32 upland soils in southern part of Korea was obtained in Acaulospora sp., Gigaspora sp. and Glomus sp., respectively. As a result of dual inoculation of Glycin max cv. Dajangkong and Eunhakong both with $1{\times}10^8$cells of B. japonicum YCK 213 and 10 spores of each mycorrhiza in vermiculite pot, only Glomus sp. treatment together with the rhizobium showed significant increase ($P{\leqq}0.05$) both in shoot dry wt and nodule mass of not Eunhakong but Dajangkong. In red-yellow soils with pH 5.2($1:5H_2O$) and 203 mg of Lancaster P per kg of soil, in which $10^3$ cells of B. japonicum and $10{\pm}0.2$ spores of mycorrhizae per gram of soil were naturalized, grain yield of G. max cv. Dajangkong was increased to 3.9% by dual inoculation both of $4.8{\times}10^6$cells of B. japonicum and 10 spores of mycorrhizae per two seeds under condition applied with 30 kg $P_2O_5$ and 34 kg $K_2O$ per hectare compared to conventionally fertilized plot (2.75 MT $ha^{-1}$) added with 30 kg N $ha^{-1}$. However, there was not significant.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.5
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• pp.803-810
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• 1995

Co-immobilized mixed culture system(A-Z system) composed of two different oxygen-demanding strains, aerobic(Aspergillus awamori) and anaerobic(Zymomonas mobilis) strains, in a Ca-alginate gel beads was developed to increase ethanol production from raw starch as a carbon source. Optimal mixture ratio of A. awamori and Z. mobilis was $1.25{\times}10^{9}\;spores/L-gel$ and 0.5g cells/L-gel, respectively. After 120 hours of cultivation, gel beads distinguished oxygen-rich surface for A. awamori from oxygen-deficient central part for Z. mobilis. At A-Z culture system, yield of ethanol on glucose, $Y_{p/s}=0.18$, was very low and there was high leakage of cells from surface of gel beads. At A-Z 36 cultrue system with changing silicon check valve for cotton plug at 36 hours in A-Z culture system, there was no cell leakage from gel beads, pH was maintained at around 4.3 during cultivation, and yield of ethanol on glucose, $Y_{p/s}=0.36$, showed 2 times higher than that of control culture system(cotton plug culture).

• Journal of the Korean earth science society
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• v.26 no.3
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• pp.276-282
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• 2005

The Quaternary palynoflora from Cheongsu core, drilled on the western part of the Jeju Island, consists mainly of deciduous broad-leaved angiosperms and herbs. Dominant taxa are Pinaceae, Alnus, Castanea/Castanopsis, Ulmus/Zelkova, Chenopodiaceae and Compositae. Based on palynofloral composition, two palynostratigraphic zones are recognized. Zone I is characterized by a predominance of Alnus and Chenopodiaceae, and by the abundance of herbs. Zone II is dominated by conifers and deciduous broad-leaved angiosperms, including Abies, Taxodiaceae-Cupressaceae-Taxaceae, Ulmus/Zelkova and Gramineae. The Cheongsu palynoflora can be correlated with Alnipollenites(Alnus)-Chenopodipollis(Chenopodiaceae)-Compositae Assemblage Zone of the East China Sea and is assigned to the Pleistocene in age. Ecology of main taxa and comparison with the present vegetation of Korea suggest a cool temperate climate and a low relief in the Jeju Island during the deposition of the Cheongsu core sediments.

• Mycobiology
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• v.46 no.3
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• pp.283-286
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• 2018

Fusarium graminearum causes the devastating plant disease Fusarium head blight and produces mycotoxins on small cultivated grains. To investigate the timeframe of F. graminearum infection during rice cultivation, a spore suspension of F. graminearum was applied to the rice cultivars Dongjin 1 and Nampyeongbyeo before and after the heading stage. The disease incidence rate was the highest (50%) directly after heading, when the greatest number of flowers were present, while only 10% of the rice infected 30 days after heading showed symptoms. To understand the mechanism of infection, an F. graminearum strain expressing green fluorescent protein (GFP) was inoculated, and the resulting infections were visually examined. Spores were found in all areas between the glume and inner seed, with the largest amount of GFP detected in the aleurone layer. When the inner part of the rice seed was infected, the pathogen was mainly observed in the embryo. These results suggest that F. graminearum migrates from the anthers to the ovaries and into the seeds during the flowering stage of rice. This study will contribute to uncovering the infection process of this pathogen in rice.

• Korean Journal of Veterinary Pathology
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• v.2 no.1
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• pp.53-60
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• 1998

A fourteen-month-old Holstein bull from a private cattle fattening farm at Ansung county in Kyunggi Province Korea was submitted on August 2nd 1997, for examination at the Pathology Division of the National Veterinary Research Institute. The bull died within 24 hours after developing clinical signs of abrupt inertia, complete anorexia high fever(40.3℃) diffuse severe emphysematous swelling of upper part of the right hind leg lateral recumbancy and paralysis. At necropsy diffuse severe subcutaneous redness and influx of serosanguinous exudate containing gas bubbles had accumulated under the thorax right hip and upper region of right hind leg. Muscles in upper right hind leg were blackish to dark red and yellowish brown in color. Muscle bundles were dry and separated by gas bubbles and serosanguinous fluids and muscles sections from affected regions floated in water. Histopathologically muscle fibers were partially or entirely degenerated fragmented and separated by exudate and gaseous substance mixed with polymorphonuclear cells. Blood vascular walls in affected regions showed severe acute fibrinoid necrosis. Typical large rod-shaped bacteria with or without oval central to subterminal spores were frequently observed in tissue sections stained with H-E and Gram stain. The large Gram-positive anaerobic endospore-producing rods were isolated from the suspension of muscle lesions. Isolated bacteria were identified as Clostridium(CL) chauvoei and CL. sordellii by biochemical tests. This case was diagnosed as blackleg based on the typical clinical signs gross finding histopathological observation and bacteriological results. This is the first case report on blackleg associated with Cl. chauvoei and Cl. sordellii in Holstein cattle in Korea.