• Animal Systematics, Evolution and Diversity
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• 제27권2호
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• pp.197-200
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• 2011

Tunicates were collected from three harbors (Gampo, Bangeojin, Daebyeon) in Gyeongsangnam-do and one harbor (Seogwipo) in Jejudo Island during the period from August 2008 to January 2011 and were identified on the basis of their morphological characteristics. Among them, colonial tunicate Clavelina lepadiformis (Muller, 1776) belonging to the family Clavelinidae was found to be an invasive alien species introduced from the North Atlantic, and this is the first record of its occurrence in Korea.

• 한국자기공명학회논문지
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• 제8권2호
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• pp.115-126
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• 2004

Four secondary metabolites from an unidentified tunicate were isolated by treatment with trichloroethyl chloroformate(TECF) or acetic anhydride in pyridine. Their structures were determined by an extensive NMR analysis and the configuration of diacetyl derivatives(3a, 4a) was assigned by comparing with NMR data of a similar compound. Three new naturally occurring compounds (1, 3, 4) showed potent brine shrimp lethality and antifungal effect against Candia albicans.

• 한국어병학회지
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• 제23권3호
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• pp.313-322
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• 2010

Edible tunicate Halocynthia roretzi, one of the most commercially important aquatic organisms in Korea, has been killed by tunic softness syndrome since last decade. The intracellular protistan parasite observed by the transmission electron microscope in hemocytes of the tunicate was considered to be the causative agent of the mass mortality. The goal of the present work is to examine the characteristic features of the parasite by identifying the 18S rDNA sequences of the parasite. The experiments conducted include amplification of presumptive 18S rDNA from diseased tunicate tissues with UNonMet-PCR and sequencing the product. A preliminary phylogenetic analysis was performed on the presumptive parasite rDNA. A digoxigenin labeled DNA probe was designed on the basis of the sequences of rDNA. Dig-ISH assay was conducted to diagnose the protistan parasite. A PCR using UNonMet-PCR primer generated 595 bp SSU rDNA fragment. Subsequently, PCRs with primer pair expended this sequence to 1542 bp. This is the first partial sequences of SSU rDNA gene to be published on the protistan parasite that has presumed causing the mass mortality of tunicate. Since the Dig-ISH technique demonstrated the presence of infection in hemocytes on the all host tissues, the fragment was confirmed to be the intracellular protistan parasite SSU rDNA. A phylogenetic analysis suggested that the protistan parasite may be a unique eukaryote that is closely related to Apicomplexa.

• Natural Product Sciences
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• 제13권2호
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• pp.132-134
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• 2007

An analog of antibacterial sulfated alkene against Bacillus subtilis was isolated from a species of tunicate (Mideoduck), Styela clava, cultured at Jindong Bay, Korea. The structure was determined as 4,8-dimethyl-3-nonenyl sulfate by MS and spectral analysis such as UV IR and NMR.

• 한국수산과학회지
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• 제13권2호
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• pp.57-64
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• 1980

우렁쉥이, Halocynthia roretzi (V. DRASCHE)가 서식하지 않는 서해안 고군산열도의 선유도와 어청도 구성에 충무산 우렁쉥이 종묘를 이식하고, 1978년 4월부터 1979년 3월까지 333일에 걸쳐 이식후의 성장과 해양환경의 가능성에 대하여 검토 하였다. 1. 이식당시의 평균 체고 1.84mm, 체폭 1.42mm 체중 15.0mg이 이식후 만 333일만에 선유도구역은 평균 체고 10.77mm, 체폭 6.75mm, 체중 201mg의 아주 낮은 성장을 보였으나, 어청도구역은 체고 13.5mm, 체폭 11.51mm, 체중 880mg으로 성장되는 종묘 양성장으로 가능하다. 2. 연간 수온의 변동범위는 $6.8\~26.8^{\circ}C$로써 우렁쉥이 서식에는 제한되지 않았으나, $26.8^{\circ}C$인 7월은 성장이 아주 늦었다. 3. 염분은 $29.2\~32.0\%_{\circ}$로써 우렁쉥이 종묘의 서식에 영향이 없었다. 4. 1.0m이하의 낮은 투명도는 성장에 영향을 크게 주는 요인이었다. 5. 선유도구역은 주로 흰덩이멍게와 부이가 다량 착생되어 우렁쉥이 종묘의 표면을 덮으므로 체고는 신장되고 체중 및 체폭은 감소되어 폐사하는 개체가 많아 우렁쉥이 종묘 양식장으로는 부적당하다.

• Natural Product Sciences
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• 제21권4호
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• pp.278-281
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• 2015

Chemical investigation on a colonial marine tunicate, Didemnum sp. led to the isolation of a series of indole alkaloids including a new (1) and two known metabolites (2-3). Based on the spectroscopic analysis including 1D and 2D NMR along with MS spectra, the structure of 1 (16-epi-18-acetyl herdmanine D) was elucidated as a new amino acid derivative. The absolute configuration of 1 was determined by comparison of specific rotation with the known compound. The structures of compounds 2 and 3 were also identified as bromoindole containing compounds N-(6-bromo-1H-indole-3-carbonyl)-L-arginine and (6-bromo-^1H-indol-3-yl) oxoacetamide, respectively, based on $^1H$ and $^{13}C$ NMR data, MS data and specific rotation value. Their pharmacological potentials as antibacterial agents and FXR antagonists were investigated, but no significant activity was found. However, the structural similarity of compound 1 to compound 4 suggested the anti-inflammatory potential of compound 1.

• Natural Product Sciences
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• 제13권3호
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• pp.229-233
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• 2007

Chemical investigation of the crude extract of the Egyptian marine tunicate Eudistoma laysani led to the isolation of a new nucleoside; 3-deazainosine and four known ones; inosine, 2'-deoxyuridine, adenosine and 2'-deoxyadenosine. Structural elucidation of the isolated compounds was based on intensive studies of their spectral data including 1D ($^{1}H$ and $^{13}C$) and 2D ($^{1}H-^{1}H$ COSY, HMQC, HMBC) NMR together with mass spectra. The antioxidant effects of the isolated compounds were determined using DPPH, where they exhibited significant activities.

• Animal Systematics, Evolution and Diversity
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• 제36권3호
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• pp.236-239
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• 2020

Pelagic tunicate, Thetys vagina Tilesius, 1802, is newly reported from Korean waters. The genus Thetys Tilesius, 1802 is also first recorded as Korean fauna. Thetys vagina is the only valid species in the genus Thetys. It is distinct from other genera by having at least 16 body muscles widely interrupted, no anterior proboscis, bent alimentary canal in the solitary oozooid, and five narrow body muscles, no ventral peduncle, an almost compact loop alimentary canal in the aggregate blastozooids. The specimens of T. vagina examined in this study were collected at the subtidal zone of Ulleung-do Island by scuba diving. In this paper, the detailed descriptions and photographs of both the solitary and aggregate living forms of T. vagina are provided.

• 한국동물학회:학술대회논문집
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• 한국동물학회 2000년도 공동 춘계학술대회
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• pp.79.2-79
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• 2000

No Abstract, See Full Text

• 한국동물학회:학술대회논문집
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• 한국동물학회 2000년도 공동 춘계학술대회
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• pp.79.1-79
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• 2000

No Abstract, See Full Text