• ALGAE
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• 제29권4호
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• pp.311-319
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• 2014

The biocide sodium hypochlorite (NaOCl) is widely used for controlling algal growth, and this application can be extended to marine environments as well. This study evaluates the biocidal efficiency and cellular toxicity of NaOCl on the harmful dinoflagellate Cochlodinium polykrikoides, with emphasis on pigment production and antioxidant enzyme activity. The test organism showed dose-dependent decrease in growth rate on exposure to NaOCl, and the 72 h $EC_{50}$ was measured to be $0.584mg\;L^{-1}$. NaOCl significantly decreased pigment levels and chlorophyll autofluorescence intensity, indicating possible detrimental effects on the photosystem of C. polykrikoides. Moreover, it significantly increased the activities of antioxidant enzymes, suggesting the production of reactive oxygen species in the cells. These data indicate that NaOCl exerted deleterious effects on the photosynthetic machinery and induced oxidative damage in the dinoflagellate and this biocide could be effectively used for the control of algal blooms.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 추계수산관련학회 공동학술대회발표요지집
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• pp.141-142
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• 2000

To elucidate the ichthyotoxic mechanisms of a harmful dinoflagellate Cochlodinium polykrikoides, biochemical and hematological responses of fish exposed to blooms were investigated. Particularly, based on our finding that oxidative damages of gill were associated with fish mortality, dysfunction of ion-transporting enzymes and secretion of gill mucus of fish exposed to this bloom species were examined. (omitted)

• ALGAE
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• 제21권3호
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• pp.283-286
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• 2006

This study carried out phylogenetic analysis of dinoflagellate Gonyaulax polygramma which was responsible for a harmful algal bloom episode in Korea in 2004. Molecular phylogenetic tree inferred from the partial LSU rDNA data showed that G. polygramma came up among the monophyletic Gonyaulax clade, but did not have apparent genetic affiliation to other Gonyaulax species. This result appears to be consistent with characteristic morphological features of G. polygramma such as epitheca sharply tapering to the apex and thecal plates ornamented with numerous longitudinal striations.

• 환경생물
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• 제28권1호
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• pp.20-29
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• 2010

Cochlodinium polykrikoides has occurs regularly during the summer in the South Sea of Korea. To investigate photosynthetic pigments concerned with phytoplankton community structure as bloom of Cochlodinium polykrikoides, the experiment was sampled at 20 stations three times between July and September 2002 in the Southern Sea of Korea. The distribution of peridinin, the biomarker of dinoflagellate, was higher at the blooming time than it was before and it disappeared after bloom. The correlative coefficients between Chl. a and peridinin at the blooming time and out of bloom were 0.9253 and 0.1613, respectively. This result indicated that the bloom was caused by dinoflagellate. The correlative coefficients between Chl. a and fucoxanthin were 0.3282 and 0.9759, respectively, and the correlative coefficients showed the succession from dinoflagellate to diatom. This result means that the bloom of Cochlodinium polykrikoides can be detected by Chl. a information from satellite remote sensing. Therefore, if the algorithm to detect peridinin in addition to Chl. a were to be developed, dinoflagellate red tide could be monitored more effectively.

• ALGAE
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• 제26권2호
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• pp.181-192
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• 2011

Ballasting and deballasting of shipping vessels in foreign ports have been reported worldwide as a vector of introduction of non-native aquatic plants and animals. Recently, attention has turned to ballast water as a factor in the global increase of harmful algal blooms (HABs). Many species of microalgae, including harmful dinoflagellate species, can remain viable for months in dormant benthic stages (cysts) in ballast sediments. Over a period of four years, we surveyed ballast water and sediment of ships docked in two ports of Tampa Bay, Florida, USA. Sampling conditions encountered while sampling ballast water and sediments were vastly different between vessels. Since no single sample collection protocol could be applied, existing methods for sampling ballast were modified and new methods created to reduce time and labor necessary for the collection of high-quality, qualitative samples. Five methods were refined or developed, including one that allowed for a directed intake of water and sediments. From 63 samples, 1,633 dinoflagellate cysts and cyst-like cells were recovered. A native, cyst-forming, harmful dinoflagellate, Alexandrium balechii (Steidinger) F. J. R. Taylor, was collected, isolated, and cultured from the same vessel six months apart, indicating that ships exchanging ballast water in Tampa Bay have the potential to transport HAB species to other ports with similar ecologies, exposing them to non-native, potentially toxic blooms.

• 한국해양학회지:바다
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• 제15권1호
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• pp.36-40
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• 2010

선박평형 수는 유독 와편모조류 및 다양한 미세조류의 국제적인 이동경로로 알려져 있다. 본 연구에서는 선박평형 수에 있는 와편모조류의 다양성을 조사하기 위하여 와편모조류 특이적인 PCR primer와 종 특이적인 real-time PCR 유전자 탐침자를 이용하였다. 선박평형 수 시료에 대한 광학현미경 조사에서는 와편모조류가 매우 낮은 농도로 관찰되었지만, SSU rDNA의 cloning 및 염기서열 분석 결과에서는 기생 와편모조류, 초미세플랑크톤, 어패류 폐사 원인종 등 다양한 종류가 확인되었다. 본 연구 결과는 종 톡이적 PCR primer와 같은 분자생물학적 방법이 선박 평형 수에 외래 유입종의 신속 정확한 진단에 유용함을 보여주고 있다.

• Fisheries and Aquatic Sciences
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• 제7권3호
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• pp.122-129
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• 2004

Harmful Cochlodinium polykrikoides is a notorious harmful algal bloom (HAB) species that is causing mass mortality of farmed fish along the Korean coast with increasing frequency. We analyzed the sequence of the large subunit (LSD) rDNA D1-D3 region of C. polykrikoides and conducted phylogenetic analyses using Bayesian inference of phylogeny and the maximum likelihood method. The molecular phylogeny showed that C. polykrikoides had the genetic relationship to Amphidinium and Gymnodinium species supported only by the relatively high posterior probabilities of Bayesian inference. Based on the LSU rDNA sequence data of diverse dinoflagellate taxa, we designed the C. polykrikoides-specific PCR primer set, CPOLY01 and CPOLY02 and developed PCR detection assays for its sensitive, accurate HAB monitoring. CPOLY01 and CPOLY02 specifically amplified C. polykrikoides and did not cross-react with any dinoflagellates tested in this study or environmental water samples. The effective annealing temperature $(T_{p})$ of CPOLY01 and CPOLY02 was $67^{\circ}C$. At this temperature, the conventional and nested PCR assays were sensitive over a wide range of C. polykrikoides cell numbers with detection limits of 0.05 and 0.0001 cells/reaction, respectively.

• 한국해양학회지:바다
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• 제7권4호
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• pp.2221-2221
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• 2002

한국 서해안의 곰소만에서 숙주-기생자 배양체 Prorocentrum minimum- Amoebophrya sp.를 분리하여 실험, 배양하는데 성공하였다. 본 연구는 이 숙주-기생체를 실험배양 하면서 광학 및 형광현미경 관찰을 토대로 규명된 적조생물 P minimum을 숙주로 하는 기생성 와편모류 Amoebophrya sp.의 생활사 단계를 보고한다. 이 기생성 와편모류에 의한 감염은 숙주 P minimum의 핵 내부에서 일어나고, 성장하여 결국은 세포질을 포함한 숙주 세포 공간의 대부분을 차지한다. 이 영양체의 세포 내의 성장이 완결되면 숙주의 각을 열고 세포 밖으로 나온다. 숙주 세포 밖의 자유유영 생활사 단계인 vermiform stage를 거쳐, 순간적으로 발산하여 수많은 dinospore를 형성하는 단계에 이른다. 우리나라 연안해역에서 춘·하계에 대규모 적조를 일으키는 원인 생물인 P. minimum과 이에 기생하는 본 Amoebophrya sp.의 숙주-기생배양체는 생물학적 적조제어기술 개발을 위한 중요한 생물재료의 하나이다.

• 한국해양학회지:바다
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• 제7권4호
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• pp.221-225
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• 2002

한국 서해안의 곰소만에서 숙주-기생자 배양체 Prorocentrum minimum- Amoebophrya sp.를 분리하여 실험, 배양하는데 성공하였다. 본 연구는 이 숙주-기생체를 실험배양 하면서 광학 및 형광현미경 관찰을 토대로 규명된 적조생물 P minimum을 숙주로 하는 기생성 와편모류 Amoebophrya sp.의 생활사 단계를 보고한다. 이 기생성 와편모류에 의한 감염은 숙주 P minimum의 핵 내부에서 일어나고, 성장하여 결국은 세포질을 포함한 숙주 세포 공간의 대부분을 차지한다. 이 영양체의 세포 내의 성장이 완결되면 숙주의 각을 열고 세포 밖으로 나온다. 숙주 세포 밖의 자유유영 생활사 단계인 vermiform stage를 거쳐, 순간적으로 발산하여 수많은 dinospore를 형성하는 단계에 이른다. 우리나라 연안해역에서 춘·하계에 대규모 적조를 일으키는 원인 생물인 P. minimum과 이에 기생하는 본 Amoebophrya sp.의 숙주-기생배양체는 생물학적 적조제어기술 개발을 위한 중요한 생물재료의 하나이다.

• 한국수산과학회지
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• 제37권3호
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• pp.202-208
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• 2004

The spatio-temporal distribution of dinoflagellate resting cysts was investigated by palynological processing to understand the harmful algal bloom (HAB) potential in the sediment of the Saemangeun area in 2003. In total, thirty-two dinoflagellate species were identified, and their concentrations were in the range of $6-1,618\;cysts{\cdot}g^{-1}$ (dry weight). The concentrations of resting cysts were higher in the spring (26 species, $64-1,101\;cysts{\cdot}g^{-1})$ and summer (30 species, $81-1,618\;cysts{\cdot}g^{-1})$ than in the autumn (32 species, $6-1,150\;cysts{\cdot}g^{-1})$ and winter (24 species, $25-728\;cysts{\cdot}g^{-1}).$ The composition rate of the heterotrophic dinoflagellate species to the total, which is closely related to the eutrophication process, to ranged from 6 to $29\%$ in the study area. The most dominant species was toxic Alexandrium tamarense/catenella $(25\%)$ followed by Gonyaulax scrippsea $(9\%)$ and toxic Protoceratium reticulatum $(5\%).$ Given the high abundance of the toxigenic dinoflagellate species, the Saemangeun area is considered to have the great potential for HABs in the future.