• Journal of Microbiology and Biotechnology
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• 제12권1호
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• pp.176-181
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• 2002

In order to isolate and identify Bifidobacterium spp. that originated in Korea, feces were sampled from healthy Korean adults and children living in three villages, the first having a history of longevity and the other two where the diet did not include fermented milk or any pharmaceutical preparations. Through the use of Gram staining and microscopic examination for cell morphology, 23 bacterial strains presumed to be the Bifidobacterium genus were isolated from the feces of 13 out of a total of 59 Korean people. To identify the Bifidobacterium strains at the genus level, these bacteria were then analyzed by TLC and the fructose-6-phosphate phosphoketolase (F6PPK) test. The result showed that 22 of the isolated strains were confirmed to be members of the genus Bifidobacterium. All of these bifidobacteria were also identified as Bifidobacterium spp. by the fermentation test. Using a RFLP analysis, an attempt was made to identify the Bifidobacterium spp. that had been isolated from both Korean adults and children. In a genomic Southern blot analysis after digestion with two restriction enzymes (EcoRI, HindIII), all of the 14 randomly selected Korean isolates showed patterns identical to those of three different B. longum species. Another restriction enzyme, CfoI (4-bp recognition enzyme), was then used to identify the strain. Interestingly, all the Korean isolates were identified as B. longum ATCC 15708, indicating that a RFLP analysis was effective for identifying Bifidobacterium spp. at both the strain and species levels.

• Mycobiology
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• 제38권4호
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• pp.249-255
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• 2010

We identified Lacrymaria velutina of the Coprinaceae in Korea. The unusually large and sturdy fruiting body, fibrillose to fibrillose-scaly cap and stalk without a volva with an obscure superior hairy ring zone or hairy annulus, and blackish brown, warted spores distinguished this species from closely related Psathyrella species. An illustrated account of the microscopic traits is presented. Fruiting bodies with obtusely hemispherical caps, 2.5~6 cm, becoming convex with age; surface dry, densely fibrillose-scaly with split margin; stipe, 4.5~6 cm, equal, hollow, fibrillose, dry, whitish above the superior ring zone, light brown below; crowded gills, adnexed, dark black at maturity. Pileipellis typically cellular with the gill edge appearing white and beaded. Blackish brown basidiospores that discolor in concentrated sulfuric acid. Spores elliptical, warted, $9\sim11{\times}6\sim8{\mu}m$, with prominent snout-like germpores. Cheilocystidia abundant, $57\sim68{\times}19\sim25{\mu}m$, and narrowly elongated clavate, often clustered in threes or fours. Pleurocystidia rarely present, $45\sim47.5{\times}12\sim13{\mu}m$, and clavate to utriform. This trait distinguishes our sample as L. velutina from other Psathyrella spp. of the Coprinaceae, which have smooth spores. This taxon was clarified by the observation that Psathyrella spores fade in concentrated sulfuric acid. A molecular phylogenetic study revealed that our specimen was Lacrymria velutipes, which is closely related to Lacrymaria lacrymabunda. Moreover, those two species are clearly distinguishable from other Psathyrella species, which agreed with the morphologically distinctive traits described above. We believe that this is the first report of this taxon, which has not been described in Korea.

• 기술혁신연구
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• 제22권4호
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• pp.117-143
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• 2014

기존의 기술 진화 경로 연구는 주로 거시적 동향 분석 수준에서 이루어져 왔으며 포괄적인 기술정책 방향 수립에는 시사점이 있었으나, 기업 기술 및 특허전략에는 활용가치가 낮았다. 2000년대부터 논문 및 특허 등의 데이터를 활용해 미시적인 기술의 진화 경로를 분석하고, 기업 기술전략에 적용하려는 연구가 증가하고 있다. 그러나 대부분 과거 진화 경로의 서술에 그치고 있으며 기술의 진화 또는 파생-융합 등의 변화에 대한 분석은 전문가의 정성적 판단에 상당부분 의존하고 있다. 본 연구에서는 특허 인용 네트워크를 구축해 미시적 기술의 진화 경로를 도출하고, 기술의 진화와 파생을 동적 기술트리를 통해 분석하는 방법론을 제시한다. 동적 기술트리 분석은 기술의 핵심요소를 체계화하고, 신기술 요소의 신규성과 확장성을 평가해 차세대 기술진화와 파생에 대한 정량적 판단을 가능하게 한다. 이를 통해 차세대 신기술과 파생기술에 대하여 파악, 평가, 비교하고 나아가 예측의 토대를 구축한 것이 본 연구의 의의이다. 본 연구의 결과는 기술 및 특허전략과 포트폴리오 구축의 신뢰성을 높일 수 있는 좋은 도구가 될 것이다. 본 연구에서 제안한 방법론을 이용하여 최근 전력산업에서 기존 교류 송전의 대안으로 주목을 받고 있는 초고압 직류송전 시스템 기술을 대상으로 실증분석을 수행하였다.

• 한국양식학회지
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• 제18권3호
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• pp.207-214
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• 2005

We report on the diagnosis, pathology, and taxonomy of Perkinsus sp. infection in Manila clams (Ruditapes philippinarum) from Korean waters. Amplimers were designed from internal portions of the non-transcribed spacer (NTS) of P. atlanticus for molecular diagnosis of Perkinsus infection. PCR-based identification methods and an in situ hybridization assay were developed for detection of Perkinsus sp. in live tissues as well as in histological preparations. Hybridization signals were observed around the nucleus of trophozoites. Positive results from PCR and in situ hybridization indicated that Korean Perkinsus sp. is genetically identical with P. atlanticus reported in Europe, which is currently synonymous with P. olseni reported from Australia. Microscopic morphological features of different lift stages of Perkinsus sp. appeared very similar to those of P. atlanticus. Severely infected clams often exhibited white nodules on their mantles and gills as a consequence of inflammation. In lightly to moderately infected clams, Perkinsus sp. was mainly found in gill tissues, whereas the protozoan parasites were found in digestive tracts, gonadal tissues, and foot tissues of heavily infected clams. It is likely that the gills are the portal of the infection and that P. olseni spreads to other tissues as the infection advances. In conclusion, by considering the taxonomic priority of P. olseni, Korean Perkinsus sp. is accepted as P. olseni. P. olseni appears to be common on tidal flats on the western and southern Korean coasts and is considered to be a pathogen capable of causing mass mortality of clams.

• 한국식품영양학회지
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• 제22권1호
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• pp.103-109
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• 2009

현재까지 미생물에 의해 생산되는 10,000여 종의 항생물질 가운데 약 2/3 에 해당하는 64% 정도가 방선균으로부터 발견되었다. 따라서 토양 중에 널리 분포하고 있는 방선균을 분리하여 광범위 항생물질 생산능이 가강 우수한 Y-88을 최종 선정하였다. 이 균을 형태학적, 생리상 및 배양학적으로 동정한 결과 Streptomyces 속으로 밝혀져 Streptomyces sp. Y-88 이라 명명하였다. Y-88로부터 항생물질 생산 최적 배양조건을 검토한 결과 soluble starch 1.6%, glucose 1.6%, beef extract 0.6%, $K_2HPO_4$, $MgSO_4$ $7H_2O$ 및 $ZnSO_4$ $7H_2O$가 각각 0.01%였으며, 최적 pH4.0, 배양온도 25$^{\circ}C$ 그리고 배양시간으로 위의 조건에 30시간에서 항생물질 생산이 빠른 것으로 나타났다.

• 자원환경지질
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• 제9권1호
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• pp.45-73
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• 1976

This study has been made for the enlargement of a previous work of 1964 which was carried out by an author of this work emphasizing the stratigraphy, micropaleontology, depositional environment, and structural tectonics of the studied area. The stratigraphic sequences of the area are groupped into four units: (1) basement of Pre-Cretaceous, (2) lower sediments of Late Cretaceous, (3) upper sediments of Late Cretaceous and (4) igneous rocks of Late Cretaceous and Tertiary (?). The oldest rocks consisting of schists and gneisses of Pre-Cambrian and schistose granite' of Jurassic age are exposed at the base of this area on which the thick Cretaceous sediments were deposited. These old rocks are unconformably overlain by the lower sedimens of Late Cretaceous composed of three members, an alternation of black shale and tuffaceous sediments, fine tuff and rhyollite flow in ascending order. The oily material was found from the black shales of the alternation m"ember as semi-solid greaselike material, oily order and microscopic granular spherical material and oily stain. The lower sediments are also overlain, in low-angleunconfromity, by the 'upper sediments having three members, an alternation of volcanic conglomerate and andesitic tuff, rhyollitic tuff and andesite flow in the same order. The igneous suit of diabase, diorites, biotite granite, porphyritic granite and porphyries of the latest Cretaceous and small exposure of pitchstone of Tertiary (?) intruded into the pre-existed rocks above mentioned. Considerable amount of ostra- coda microfossils have been chemically extracted from the black shales of the lower sediments and the identification of the fossils suggests that the depositional environment of the sediments were under fresh or brackish water condition. The distribution of the geology and its tectonic data also suggest a combination of dome and basin structures in the area of San-i peninsula and Jin-do as shown in fig. 8. Between these two units an anticlinal structure was constructed. As a result of this study, a seismic survey in a district between U-su-yong and north coast of Jin-do is recommended to determine the underground features.

• 한국환경과학회지
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• 제23권12호
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• pp.2015-2028
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• 2014

We analyzed with HPLC (High Performance Liquid Chromatography) analysis photosynthetic pigments and environmental factors, microscopic observations of the phytoplankton and zooplankton in the seawater every month from February 2009 to November 2010 in Haengam Bay. The level of dissolved inorganic nutrients was the highest between July and September, when freshwater influx was at its peak, whereas chlorophyll a levels were the highest in April and August. Also, phytoplankton pigment concentration increased when dissolved inorganic nutrients are carried into nearshore waters by rainfall runoff. Based on identification of phytoplankton and photosynthetic pigments results, diatoms were mainly dominant while dinoflagellate populations increased at July and August 2009, May 2010. The zooplankton communities are dominated in terms of Noctiluca scintillans. The contribution of Noctiluca scintillans in 2010 accounts for approximately 77.3% of the total zooplankton. Distribution patterns over time of zooplankton in the seasonal distribution of phytoplankton showed a different pattern.

• Parasites, Hosts and Diseases
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• 제48권3호
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• pp.213-217
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• 2010

Sarcocystis sp. infection was investigated in 20 necropsied captive wild mammals and 20 birds in 2 petting zoos in Malaysia. The gross post-mortem lesions in mammals showed marbling of the liver with uniform congestion of the intestine, and for birds, there was atrophy of the sternal muscles with hemorrhage and edema of the lungs in 2 birds. Naked eye examination was used for detection of macroscopic sarcocysts, and muscle squash for microscopic type. Only microscopically visible cysts were detected in 8 animals and species identification was not possible. Histological examination of the sections of infected skeletal muscles showed more than 5 sarcocysts in each specimen. No leukocytic infiltration was seen in affected organs. The shape of the cysts was elongated or Circular, and the mean size reached $254{\times}24.5{\mu}m$ and the thickness of the wall up to $2.5{\mu}m$. Two stages were recognized in the cysts, the peripheral metrocytes and large numbers of crescent shaped merozoites. Out of 40 animals examined, 3 mammals and 5 birds were positive (20%). The infection rate was 15% and 25% in mammals and birds, respectively. Regarding the organs, the infection rate was 50% in the skeletal muscles followed by tongue and heart (37.5%), diaphragm (25%), and esophagus (12.5%). Further ultrastructural studies are required to identify the species of Sarcocystis that infect captive wild animals and their possible role in zoonosis.

• 한국물환경학회지
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• 제34권3호
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• pp.285-292
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• 2018

This study was performed in order to identify the red tide-causing organism and to understand the characteristics of the water quality during the winter of 2015 and 2016 in the Oncheon stream, a tidal river in Busan, where red tide often occurs in the wintertime. Two sites were selected on the stream and the surface water was sampled a total of 28 times during the experimental period. Twelve water quality characteristics, including water temperature, pH, DO, COD, total-N (T-N), total-P (T-P), and salinity were analyzed in order to test water quality. The cell numbers of cryptomonads were counted directly by microscopic observation. The nucleotide sequences of the partial 28S rRNA gene and psbA gene from metagenomic DNA, derived from each sampling site, were analyzed. According to the results, the alga most responsible for the bloom was identified as Teleaulax OC1 sp., which belongs to the cryptomonads. Three items of chl-a, pH, and DO were positively correlated with the cell numbers of the cryptomonads counted at the upper stream of the tidal area (St 1) while eight items of chl-a, TOC, BOD, total-N, COD, SS, pH, and DO were positively correlated with the cells located at the junction between the stream and Su-young river (St 2) in the order.

• 한국산업보건학회지
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• 제27권4호
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• pp.324-332
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• 2017

Objectives: Much scientific evidence indicate a positive association between moldy environments and respiratory illnesses and/or symptoms. However, few comprehensive assessments of mold have been performed for such settings. Spore counts or microscopic enumeration only may not be sufficient for evaluating fungal exposure. Recently, Mold Specific QPCR technology developed by the US EPA (Environmental Relative Moldiness Index, ERMI) has been widely used worldwide and great performance for assessing fungal exposure has been shown. Methods: We aimed to develop a Korean version of ERMI suitable for the distribution of fungal flora in Korea. Thirty dwellings in the Seoul and Incheon area were selected for sampling, and each was classified as 'Flooded, 'Water-damaged' or 'Non-water-damaged'. Results: Dust on the floor and airborne sampling were collected using an MAS100 and a 'Dustream' collector. Samples were analyzed by quantitative polymerase chain reaction(QPCR) for the 36 molds belonging to ERMI. Student t-test and ANOVA tests were carried out using SAS software. The median ERMI values of flooded, water damaged, and non-water damaged dwellings were 8.24(range: -5.6 to 27.9), 5.47(-25. 4 to 32.7), and -15.30(-24.6 to 14.8), respectively. Significant differences were observed between flooded and non-water damaged dwellings (P=0.001) and between water-damaged and non-water damaged dwellings (P=0.032). Conclusion: Our findings indicate that ERMI values attributed to dust samples in Korea could be applicable for the identification of flooded or water damaged buildings. However, much data is needed for continuously developing the Korean version of ERMI values.