• ALGAE
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• 제19권2호
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• pp.145-148
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• 2004

As a result of the 2-year monthly monitoring of the phytoplankton community at 3 stations in Mankyeong Estuary, Korea, we learned that cyan bacterial species of the genus Anabaena occurred at most sampling points with huge salinity differences (0.1-32.5 psu). We isolated several clones of Anabaena spp. from the monitoring stations, and screen out two euryhaline and nitrogen-fixing Anabaena clones, CB-MAL21 and CB-MAL22. The two clones were grown under various environmental gradients such as temperature (20, 30, 35 and 40$^{\circ}C$), salinity (0, 2, 5, 15 and 30psu), and $PO_4^{3-}$-P concentration (0, 1.6, 8.0, 40 and 200 ${\mu}M$M). Growth of CB-MAL21 and CB-MAL22 was measured by daily monitoring of chlorophyll fluorescence from each experimental culture for more than three serial transfers. Both the two experimental clones did not grow at 0psu. Maximal growth rates of the two clones were markedly reduced at lower $PO_4^{3-}$-P concentrations showing negligible growth at 0 and 1.6 ${\mu}M$M. However, growth of CB-MAL21 was not affected by low $NO_3^--$ concentration in culture media, showing the nitrogen-fixing ability. Maximum biomass yields of the two clones decreased dramatically at 35 and 40$^{\circ}C$. Optimal growth conditions for the two experimental clones were determined to be 20-30$^{\circ}C$, 40 ${\mu}M$M $PO_4^{3-}$-P, and wide salinity range from 5.0 to over 30psu. Best growth of CB-MAL21 was shown at (20$^{\circ}C$-15psu), which is less saline and cooler condition than those (i.e., 30$^{\circ}C$-30psu) for the best growth of CB-MAL22. The euryhaline and nitrogen-fixing CB-MAL21 strain thus can be a candidate laboratory culture for the future cyan bacterial marine biotechnology in temperate coastal waters.

• Journal of Ecology and Environment
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• 제36권4호
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• pp.407-419
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• 2013

Cyclotella species were collected at 51 sites from July 2010 to June 2013 in Korean coastal waters. A total of five Cyclotella species (C. atomus var. marina, C. baltica, C. litoralis, C. meduanae, and C. meneghiniana) were identified in this study. The diagnostic characteristics for five Cyclotella species are described, focusing on the spacing, position, number of satellite pores of the mantle fultoportula and valve face fultoportula. In addition, we put the salinity ranges of five species of Cyclotella together. Of the five Cyclotella species, C. baltica, C. litoralis and C. meduanae are newly recorded in Korea.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 1997년도 제20회 화학물질의 환경독성과 건강영향
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• pp.47-71
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• 1997

• 한국동물학회:학술대회논문집
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• 한국동물학회 1997년도 한국생물과학협회 학술발표대회
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• pp.147.1-147
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• 1997

No Abstract, See Full Text

• 미생물학회지
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• 제49권1호
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• pp.38-45
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• 2013

본 연구에서는 연안갯벌 갯지렁이(Perinereis aibuhitensis)에서 분리한 광염성 미생물, Bacillus sp. EBW4의 특성과 다양한 환경조건에서 유기물 분해능을 분석하였다. 16S rRNA 염기서열에 기초하여 동정한 결과, 균주 EBW4는 Bacillus hemicentroti $JSM076093^T$와 98.3%, Bacillus hwajinponensis SW-$72^T$와 97.96% 그리고 Bacillus algicoa $KMM3737^T$와 96.28%의 상동성을 보였다. EBW4의 생장 가능한 온도 범위는 $4-40^{\circ}C$, 염분도 범위는 0-17%, pH 범위는 5-9로 나타나 EBW4는 광염성 균주로 밝혀졌다. EBW4의 세포막을 구성하는 주요 지방산으로는 anteiso $C_{15:0}$, iso $C_{16:0}$, anteiso $C_{17:0}$, iso $C_{14:0}$ 등으로 각각 48.2, 12.1, 11.6, 9.4% 비율로 나타났다. EBW4는 탄수화물, 단백질, 지방 등 다양한 고분자 유기물을 분해할 수 있는 DNase, amylase, protease, lipase 등의 효소 활성뿐만 아니라, alkaline phosphatase, esterase (C4), leucine arylamidase 그리고 ${\alpha}$-chymotrypsin 효소활성도 가지고 있었다. 다양한 염분 농도 조건에서 합성폐수를 이용한 실험에서 EBW4은 조사한 모든 범위의 염분 조건에서도 유기물 분해능이 우수하였다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1997년도 한국생물과학협회 학술발표대회
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• pp.147.2-147
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• 1997

No Abstract, See Full Text

• Fisheries and Aquatic Sciences
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• 제14권2호
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• pp.93-104
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• 2011

Two hepcidin paralogs (ojhamp1 and ojhamp2) were isolated and characterized from a euryhaline Javanese ricefish (Oryzias javanicus: Beloniformes). The ojhamp1 cDNA encoded 90 or 91 amino acids (aa) of a typical HAMP1 preproprotein. This preproprotein is believed to cleave and yield the 66 or 67 aa-proprotein, followed by the 26 aa-mature peptide, composed of 8 conserved cysteine residues and the QSHL amino terminal motif. The ojhamp2 cDNA encoded 89 aa of HAMP2 preproprotein, cleaved to yield a 65 aa proprotein, and subsequently the 25 aa-mature peptide. The mature OJHAMP1 possessed a cationic isoelectric point (pI), whereas OJHAMP2 had an anionic charge. At the genomic level, both ojhamp1 and ojhamp2 share a conserved tripartite structure (three exons interrupted by two introns) with other vertebrate hepcidin genes. However, the ojhamp1 was shown to exist as two distinct mRNA species, encoding 90 or 91 aa, due to alternative splicing at the junction site between intron I and exon II. Both ojhamp1 and ojhamp2 transcripts were detected in a wide range of tissue types with varying levels of basal expression, although the highest expression was observed in the liver for both isoforms. Transcriptional response to bacterial challenge using Edwardsiella tarda showed that ojhamp1 was moderately upregulated in the liver but remained unchanged in the kidney. However, the ojhamp2 was significantly suppressed in both the kidney and liver, suggesting a potential diversification between the two paralogs.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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• pp.469-472
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• 2006

The primary objective of this study was to gain insight into the characteristics of algal blooms in relation to the marine environment of the Korean Southern Coast, using more than 22 years worth of data since the first known occurrence of algal blooms. Algal blooms tend to occur when the precipitation or water temperature for a ten-day period prior to the annual bloom exceeds the long-term mean value. There are three notable causative species in six different inner bays, namely Prorocentrum sp., Skeletonema costatum, and Heterosigma akashiwo, and in addition, these three species appeared in different conditions of water temperature and salinity at each region.

• Fisheries and Aquatic Sciences
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• 제15권1호
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• pp.57-62
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• 2012

Interspecific relationship between a euryhaline rotifer Brachionus rotundiformis and a cyclopoid copepod Apocyclops borneoensis was investigated in the laboratory culture. In a mixed culture of B. rotundiformis and A. borneoensis, population growth of B. rotundiformis was suppressed from day 10, while growth in a monoculture population continuously increased throughout the experimental period. However, the population growth of A. borneoensis in the mixed culture did not markedly differ from that in a monoculture population. Suppression of B. rotundiformis growth coincided with a decrease in the numbers of both non-egg-bearing and egg-bearing females, and increasing resting egg formation. Growth of A. borneoensis was not affected by the presence of the rotifer. However, relative growth index of ovisac bearing females in the mixed culture was 1.62 times higher than that in the monoculture. Presence of the copepod did not greatly reduce the food available to the rotifer population. The rotifer B. rotundiformis responded in a unique way, to stresses such as physical damage (filtering by A. borneoensis) with the production of many resting eggs to increase its chances of survival.

• 한국어류학회지
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• 제22권1호
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• pp.9-16
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• 2010

본 연구에서는 광염성 송사리 Oryzias dancena 성체 및 자어의 염분도 변화에 대한 내성 및 생존 능력을 평가하고자 다양한 염분도 변화 처리를 수행하였다. 담수로부터 고 염분도 조건으로의 급격한 염분도 증가 노출 처리에 대하여 O. dancena 성체는 $40^{\circ}/_{\circ\circ}$염분도 변화 폭까지 생존의 장애 없이 빠르게 적응할 수 있는 것으로 관찰되었으며, 단계적인 순치를 통할 경우 최대 $75^{\circ}/_{\circ\circ}$의 염분도 조건까지 생존이 가능하였다. 염분도의 감소 처리에서 O. dancena 성체는 $60^{\circ}/_{\circ\circ}$ 이상의 급격한 감소 폭에서도 우수한 생존율을 나타내였다. 성체와 달리 O. dancena 자어는 급격한 염분도 증가에 대한 삼투압 조절 능력 (hyper-osmoregulation)이 유의적으로 낮아 약 $15^{\circ}/_{\circ\circ}$ 이상의 염분도 증가에서는 생존에 큰 장애를 겪는 것으로 나타났다. 그러나 초기 발달 단계에 있는 자어의 염분도 변화에 대한 내성은 최초 염분도 처리 농도에 따라 염분도 변화에 대한 내성 폭이 크게 영향을 받는 것으로 관찰되었다. 초기 발달 단계에서 O. dancena 자어는 염분도 증가 보다는 염분도 감소 시 삼투압 조정 능력 (hypo-osmoregulation)이 더 높은 것으로 나타나 $40^{\circ}/_{\circ\circ}$에서 완전 담수로의 염분도 변화에서도 우수한 생존 능력을 보였다.