• Journal of Species Research
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• 제6권2호
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• pp.141-153
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• 2017

During an investigation of the biodiversity of bacterial species in Korea, we discovered many indigenous prokaryotic species. A total of 39 bacterial strains in the class Alphaproteobacteria were isolated from various environmental samples collected from marine organisms, sea water, fresh water, tap water, mud flats, activated sludge, mineral water, tidal flats, soil and decayed plants. From the high 16S rRNA gene sequence similarity (>98.7%) and formation of robust phylogenetic clades with the most closely related species, it was determined that each strain belonged to each independent and predefined bacterial species. There is no official report that any of these 39 Alphaproteobacteria species have been described in Korea. Specifically, 18 species in 11 genera in the order Sphingomonadales, 11 species in 10 genera in the order Rhizobiales, two species in two genera in the order Caulobacterales, six species in six genera in the order Rhodobacterales and two species in two genera in the order Rhodospirillales were found in Korea. Gram reaction, colony and cell morphology, basic biochemical characteristics, isolation source, and strain IDs are described in the species description section.

• 한국수산과학회지
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• 제49권1호
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• pp.38-44
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• 2016

The quality and quantity of live food sources strongly influence the success of fish production in farming operations. Thus, critical studies of live forage species are a crucial element for progress in fish aquaculture. The fat content of food is an especially important determinant of growth in marine fish. Omega-3 highly unsaturated fatty acids (HUFA) are essential components of diet that determine the nutritional value of larval fish. Euglena is a protist that has potential as a forage species. These single-celled organisms have plant and animal characteristics they are motile, elliptical in shape and 15–500 μm in diameter. Their nutritional content is excellent, but most studies have focused on cells raised in autotrophic culture. We therefore examined differences in the lipid and fatty acid contents, and the growth of Euglena cells grown under autotrophic, heterotrophic, and mixotrophic conditions. Biomass production reached 15.03 g/L, 12.28 g/L, and 3.66 g/L under mixotrophy, heterotrophy, and autotrophy, respectively. The proportional n-3 HUFA content differed among culture methods: 10.04%, 5.80% and 10.01% in mixotrophic, heterotrophic and autotrophic cultures, respectively. Mixotrophy was to be the best form of cultivation for improving the growth and nutritional content of Euglena.

• 한국어류학회지
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• 제24권1호
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• pp.1-10
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• 2012

미꾸라지, 미꾸리 및 상반교배를 통해 유도된 종간 잡종의 세포유전학적 분석을 수행하였다. 미꾸라지와 미꾸리의 염색체 수는 각각 2n=48 (12M+4SM+32A), 2n=50 (10M+4SM+36A)이었고, 잡종군들의 염색체수는 각각 2n=49 (11M+4SM+34A)였다. 모든 그룹의 염색체는 동일한 arm number (NF=64)를 갖고 있었으며, 염색체 다형현상, 암수 간 이형의 염색체는 관찰되지 않았다. 적혈구의 크기, DNA 함량을 분석한 결과 잡종군들은 미꾸라지와 미꾸리의 중간 값을 나타냈다. 염색체의 NORs (nucleolar organizing regions)은 모두 동일한 중부염색체 단완부에서 Ag-positive signal이 나타났다. 이상의 결과는 미꾸라지의 1번 중부 염색체와 미꾸리의 차단부 염색체가 Robertsonian 형의 염색체 전좌 과정을 거쳤을 것을 시사한다.

• 대한조선학회논문집
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• 제52권5호
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• pp.395-406
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• 2015

The Ballast Water Treatment System was developed to prevent the unintended transport of unwanted organisms from one region to another as demanded by the IMO (International Maritime Organization). Although various types of BWTS in the world have been developed until now and applied to various ships, there has been no systematic basis for its selection and installation. Currently, the system selection and installation are as per ship owner’s suggestion or by easy installation point of view by the shipyard. In order to organize, systemize and solve problems related to the selection and installation of BWTS, a definitive study has been performed to come up with the best alternative to derive value and criteria which were to be met for vessels which are to be equipped with BWTS. Multiple criteria were compared alongside each other during the course of this study. Accordingly an AHP (Analytic Hierarchy Process) analysis method for A, B and C companies were done for container ships with size 10,000 TEU and above. Equipment type for “A” company is “Filter, UV & TiO2” combined type. For “B” company it is “Filter & UV” combined type. Finally for “C” company it is “Electrolysis” type. Henceforth, the results of this study aims to come up with the optimum way to select the best and the most suitable BWTS for a certain vessel.

• 환경생물
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• 제21권2호
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• pp.132-141
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• 2003

We carried out a study on thermohaline structure and phytoplankton com munity in the East China Sea during early summer in 2005. As a result of marine environment and phytoplankton community, three characteristics of water type were identified. The former was characterized by the dominant species with diatoms, Chaetoceros lacinious, Ch. decipiens, Guninardia flaccida, Paralia sulcata, Pseudonitzschia pungens and Pseudosolenia calcar-avis in Chinese coastal waters, the secondary was done by lower water temperature, salinity and the dominant species with dinoflagellates, Prorocentrum donghaiense and Ceratium fusus, in over-all areas and the latter was done by the dominant species with coastal species of diatoms, Skeletonema costafum and Nitzschia longissima and silicoflagellate, Dictyocha speculum var. octopers in the transfer areas of Chinese continental coastal waters. Phytoplankton community in the surface layer identified a total of 66 species belonging to 36 genera. Dominant species was Prorocentrum donghaiense, Chaetoceros lacinious, Skeletonema costatum. Standing crops of phytoplankton in the surface layer flue tuated between $1.5 \times 10^4$cells $L^{-1}$ and $3.5\times 10^{5}$ cells $L^{-1}$. And the highest value appeared in the Changjiang estuaries with high dominance by diatoms and lowest one occurred in the southwestern area of Jeju Island with high dominance by dinoflagellates. Red tides with dinoflagellate, Prororcentrum donghaiense appeared in the frontal areas with mazimum cell density, $3.4\times 10^5$ cells $L^{-1}$. And outbreak environments was low water temperature under $20^{\circ}C$, and low salinity under 31.55 psu. The vertical distribution of red tide organisms went to about 30m depth from surface.

• 환경생물
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• 제21권2호
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• pp.164-169
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• 2003

유기주석화합물은 농업과 산업분야에서 많이 쓰이고, 이들은 수계환경으로 유입되어 물이나 저질 중의 세균들에 의해 분해되어 최종적으로는 무기주석으로 된다. Trialkyltin 화합물이 해양생물에 미치는 영향에 관해서는 많은 연구가 있지만, 해양생태계에서 기초적인 생산을 담당하는 플랑크톤류에 미치는 영향에 관해서는 잘 알려져 있지 않다. 본 연구에서는 TBT와 TPT의 분해물인 DBT, MBT, DPT, MPT를 비롯하여 trimethyltin(TMT)과 그분해물인 dimethyltin (DMT)이 기수산 rotifer의 생존에 미치는 독성(96hr-$LC_{50}$)을 조사.비교하였다. 그 결과, DPT(13.8ppb)가 가장 강했으며 TMT(42.9), DBT(80.6), MPT(262.2), MBT와 DMT(>1,000)의 순으로 나타났다. 즉, trialkyltin과 dialkyltin에서는 페닐주석, 부칠주석, 메칠주석의 순으로 독성이 약해지며, mo-noalkyltin에서도 페닐주석화합물이 메칠주석화합물에 비해 독성이 강하다는 것을 확인할 수가 있었다. 이렇듯 독성이 서로 다른 것은 유기주석화합물의 소수성(lipo-philicity)과도 높은 상관이 있었다.

• Animal Systematics, Evolution and Diversity
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• 제28권4호
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• pp.279-290
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• 2012

Plecoglossus altivelis (ayu) is an amphidromous fish widely distributed in Northeastern Asia from the East China Sea to the northern Japanese coastal waters, encompassing the Korean Peninsula within its range. The shore lines of northeastern region in Asia have severely fluctuated following glaciations in the Quaternary. In the present study, we investigate the population genetic structure and historical demographic change of P. altivelis at a population level in East Asia. Analysis of molecular variance (AMOVA) based on 244 mitochondrial control region DNA sequences clearly showed that as the sampling scope extended to a larger geographic area, genetic differentiation began to become significant, particularly among Northeastern populations. A series of hierarchical AMOVA could detect the genetic relationship of three closely located islands between Korea and Japan that might have been tightly connected by the regional Tsushima current. Neutrality and mismatch distribution analyses revealed a strong signature of a recent population expansion of P. altivelis in East Asia, estimated at 126 to 391 thousand years ago during the late Pleistocene. Therefore it suggests that the present population of P. altivelis traces back to its approximate demographic change long before the last glacial maximum. This contrasts our a priori expectation that the most recent glacial event might have the most crucial effect on the present day demography of marine organisms through bottleneck and subsequent increase of effective population size in this region.

• 수산해양기술연구
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• 제40권1호
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• pp.60-64
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• 2004

우리나라 남해안에서 플라스틱 붕장어 통발을 사용하는 통발어선이 연간 유실하는 통발의 개수는 통상 조업시 시용하는 통발의 2~4배인 것으로 나 타났다. 이러한 통발의 유실은 보통 조업중에 발생되므로 어구의 유실과 함께 어획물의 손실도 발생하게 된다. 어획불과 미끼가 들어있는 유실된 통발 은 붕장어뿐만 아니라 다른 해양 생물을 유인하여 어획할 수 있는 것으로 밝혀졌다. 그리고 유실된 붕장어 통발에는 어류, 갑각류, 두족류 등이 들어있었고, 이들 가운데는 붕장어의 먹이가 되는 베도라치, 청보리멸, 양태, 붉은메기와 새우류 등이 어획되어 있었다. 따라서 조업시 어획된 붕장어 이외에도 붕장어가 이들 통발 속에 들어있는 어획물을 섭이하기 위해 통발에 들어가므로서 추가적인 Ghost fishing의 가능성은 크다고 할 수 있다.

• 한국수산과학회지
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• 제50권6호
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• pp.669-674
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• 2017

Paralytic shellfish toxins (PSTs) are produced by marine dinoflagellate phytoplankton Alexandrium spp. and Gymnodinium spp. These toxins accumulate in filter feeding organisms such as bivalves and the ingestion of contaminated shellfish can cause illness in humans. The mouse bioassay (MBA) has been the preferred PST testing method worldwide for more than 50 years. However, this assay has several disadvantages, such as detection limits, non-toxic-profiles, and the ethical issues of using animals. The aim of this study was to establish an alternative to the MBA method for testing for PSTs. We optimized the analysis conditions of a post-column oxidation-high performance liquid chromatography (PCOX-HPLC) method and the Scotia Rapid Test Kit, and then compared the accuracy of these methods to the MBA method. The results demonstrated a strong correlation between the PCOX-HPLC method and the MBA, although the PCOX-HPLC method required expensive equipment and standard material, and was time consuming. The Scotia Rapid Test Kit promises to be a useful tool, as it provided rapid and qualitative results, although the method sometimes gave a false positive result that could not be explained by toxin profiles.

• 분석과학
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• 제23권5호
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• pp.477-484
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• 2010

항균제 및 자외선 차단물질, 유기인계 난연제 등과 같은 personal care products는 개인이 일상생활에서 광범위하게 사용하는 비누, 화장품, 치약 등에 포함된 합성유기화합물로 하 폐수 처리시설에서 완벽하게 제거되지 않고 생활하수에 포함된 상당수의 양이 환경 중으로 배출되고 있다. 외국사례의 경우 하천, 해양, 토양, 저질, 생물상 등 다양한 환경매체에서 검출되고 있으며, 잔류성 생물농축성이 있어 지속적으로 노출시 생태계 및 인간의 건강에 심각한 영향을 끼칠 우려가 있다. 본 연구에서는 수질환경시료 중 15종의 personal care products를 액-액추출하여 GC/MS로 분석하였으며, 방법검출한계는 $0.004\sim0.273\;{\mu}g/L$의 범위를 나타내었다. 하천수에서는 TCEP, TCPP 등 2종이 검출되었으며, 하수처리장 시료에서는 triclosan, 4-MBC, EHMC, BP-3, TCEP, TPP, TBEP 등 7종이 검출되었다.