• Ocean and Polar Research
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• v.30 no.3
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• pp.351-359
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• 2008

In an effort to develop high-resolution sea surface temperature (SST) proxies for mid-latitude regions, two massive reef-building coral species, Alveopora and Favia, were collected from Jeju and Tsushima Islands, respectively. Their skeletons were subsequently analyzed for annual growth banding, Sr/Ca and Mg/Ca ratios. Hermatypic corals are thinly distributed in the waters of Jeju Island, where Alveopora japonica was the only dominant coral species. A higher diversity of hermatypic corals were observed in the waters of Tsushima Island, where Favia sp. was the most common coral species and even forming an about 6-m-high reef structure. Both Alveopora and Favia showed annual growth layers consisting of couplets of high- and low-density bands. Sr/Ca ratio of both species and Mg/Ca ratio of Alveopora also showed seasonal variation, likely reflecting SST variation. These results suggest the possibility that Alveopora and Favia species can be used as potential SST proxies. However, this study also highlights the potential growth disturbance of middle latitude corals due to high rainfall during monsoon and low SST during winter. This possibility should be taken into account in the investigation of Sr/Ca(Mg/Ca)-SST relationships.

• Fisheries and Aquatic Sciences
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• v.20 no.12
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• pp.32.1-32.7
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• 2017

Recent in vitro studies have demonstrated that extract of soft coral Dendronephthya gigantea (SCDE) had strong anti-inflammatory activities. However, the direct effects of SCDE on anti-inflammatory activities in vivo model remained to be determined. Therefore, the present study was designed to assess in vivo anti-inflammatory effect of SCDE using lipopolysaccharide (LPS)-stimulated zebrafish model. We also investigated whether SCDE has toxic effects in zebrafish model. The survival, heart beat rate, and developmental abnormalities were no significant change in the zebrafish embryos exposed to at a concentration below $100{\mu}g/ml$ of SCDE. However, lethal toxicity was caused after exposure to 200 and $400{\mu}g/ml$ of SCDE. Treating zebrafish model with LPS treatment significantly increased the reactive oxygen species (ROS) and nitric oxide (NO) generation. However, SCDE inhibited this LPS-stimulated ROS and NO generation in a dose-dependent manner. These results show that SCDE alleviated inflammation by inhibiting the ROS and NO generation induced by LPS treatment. In addition, SCDE has a protective effect against the cell damage induced by LPS exposure in zebrafish embryos. This outcome could explain the profound anti-inflammatory effect of SCDE both in vitro as well as in vivo, suggesting that the SCDE might be a strong anti-inflammatory agent.

• Animal cells and systems
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• v.16 no.2
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• pp.135-144
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• 2012

$Dendronephthya$ $castanea$ Utinomi, 1952 is a member of the family Nephtheidae, and dominates shallow waters adjacent to the southern part of Jejudo Island, Korea. This species is a gonochoric internal brooder with a sex ratio of 1:1, and releases planulae around the time of the full and new moon from July to September, when the seawater temperature peaks. The gametogenic cycle is annual, and oogenesis (12 months) is longer than spermatogenesis (4-5 months). No difference in reproductive features including sexuality, sex ratio, gametogenesis and gametogenic cycles was found between the sympatric species $D.$ $castanea$ and $D.$ $gigantea$, and there was no temporal reproductive isolation. Investigation of the morphological taxonomy and molecular biology of these species indicates that they have very similar or identical traits, suggesting an absence of speciation and a need for taxonomic reclassification.

• Animal Systematics, Evolution and Diversity
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• v.38 no.1
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• pp.46-49
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• 2022

This study newly records a deep-sea coral, Flabellum (Ulocyathus) deludens from Korea. The specimens were collected by trawling at a depth of 100 m off Jejudo Island in 2019. The newly recorded species is described and compared with the other similar consubgeneric species in detail based on morphological characteristics, including corallum size, calicular diameter, calicular edge, face angle, edge angle, and septal arrangement. Flabellum(Ulocyathus) deludens is characterized by its solitary, highly compressed, wedge-shaped corallite with a small cylindrical pedicel, radiating inverse chevron-patterned lateral stripes on thecal faces, highly jagged calicular edges, and hexameral septal arrangement in five cycles. As a result of this study, five species in the family Flabellidae have been recorded from Korea.

• Journal of Fisheries and Marine Sciences Education
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• v.10 no.2
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• pp.211-225
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• 1998

A field experiment was carried out for fishes on entering time to a set-net, swimming speed, current speed and direction at the Dongbok-Ri coast on Cheju Island. The results of the experiment are as follows : 1. The observation results from 07:00 to 18:00 showed that coral fish, flying fish, horse mackerel, drub mackerel and striped mullet enter the set-net from 07:00 to 14:00 mainly. 2. From the result of analyzing relationships between entering time and tide, coral fish and horse mackerel tend to enter the set-net on turn of tidal current and ebb respectively. 3. The leaving rates of coral fish, flying fish, drub mackerel, and striped mullet from the set-net were 13%, 45%, 50%, and 100%, respectively but all horse mackerel remained in the net. 4. The swimming speed of coral fish, flying fish, horse mackerel and drub mackerel are 5~25cm/sec, 20~50cm/sec, 15~45cm/sec and 10~30cm/sec, respectively and their dominant speeds are 10~15cm/sec(55%), 30~35cm/sec(30%), 30~40cm/sec(60%), and 15~20cm/sec(60%), respectively.

• Natural Product Sciences
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• v.2 no.2
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• pp.102-105
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• 1996

A new glycolipid, 2-hydroxy-3 $(octadecyloxy)-propyl-{\alpha}-D-arabinopyranoside$ (1) has been isolated from Lobophytum microlobulatum and its structure has been elucidated by physical and spectral $(UV,\;IR,\;^1H,\;^{13}C\;NMR,\;FABMS)$ data.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.1
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• pp.59-69
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• 2000

Environmental factors and phytoplankton community have been bimonthly investigated in order to clarify the bioecological characteristics of coral habitats around Moonsom at the southern Cheju Island from September 1995 to July 1996. Annual mean temperature and annual mean salinity were $17.4^{\circ}C$ and 34.06 psu, respectively, showing lower temperature-higher salinity in winter and higher temperature-lower salinity in summer, which means such conditions are inadequate for coral reef formation. Nutrient concentrations represent that total nitrogen ranged from $0.07{\sim}10.08\;{\mu}M$, phosphate from $0.05{\sim}1.70\;{\mu}M$, and silicate from $3.08{\sim}21.86\;{\mu}M$. The N/P ratio showed the range of 9.59-10.60 with decreasing offshore-ward, which means the phytoplankton community could be limited by nitrogen sources. Annual mean euphotic depth was 32.0m (18.9m-48.6m) with difference according to season and reveals the close relationship with the depth of coral distribution. Chlorophyll a concentrations of phytoplankton ranged from $0.12{\sim}1.51\;{\mu}g\;L^{-1}$ and standing crops from $1.5{\times}10^3{\sim}7.0{\times}10^5\;cells\;L^{-1}$, showing higher at inshore than at offshore with a blooming in May. A total of 128 species of phytoplankton occurred in all stations, representing 99 spp. of diatoms, 26 spp. of dinoflagellates, 2 spp. of silicoflagellates and 1 sp. of blue-green algae. Diatoms are main taxa in all seasons except for occupying by dinoflagellates in summer. Among dominant species, fParalia sulcata (Ehrenberg) Cleve and Cylindrotheca closterium (Ehrenberg) Lewin & Reimann were predominant and are likely to be main food sources for coral community. Annual mean species diversity index (H') was 1.84, showing lower than around the coast line of Cheju Island.

• Animal cells and systems
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• v.1 no.3
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• pp.419-423
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• 1997

Two new marine tardigrades, florarctus kwoni n. sp. and Batillipes philippinensis n. sp. belonging to Halechiniscidae and Batillipedidae, respectively, are described on the basis of the specimens sieved from sublittoral coral sands and shell gravels of Palawan Island, the Philippines. florarctus kwoni n. sp. is characterized by the rocket-shaped aliform expansion, with the distal margin of posterior ala flattened. Batillipes philippinensis n. sp. closely resembles B. similis Schulz, 1955 and B. annulatus De Zio, 1962. However, it is clearly discernible from the former by the shape of lateral body projection between leg III and leg IV, and the relative length of cirrus E and the spine on leg IV, and from the latter by the shape of the lateral body projection and the clavar shape. This is the first report of the marine tardigrades from the Philippines.

• Journal of Marine Life Science
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• v.6 no.2
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• pp.117-123
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• 2021

Post-disturbance recovery pattern of subtidal soft corals-macroalgae mixed community and the role of water depth were investigated. The experiment was conducted in a subtidal rock wall of Munseom, Jeju Island, Korea for 2.5 years. Artificial disturbance was done at established treatment plots at depths of 10, 15 and 20 m and were then compared with undisturbed control plots. After disturbance, recovery of soft corals was very slow, whereas macroalgae quickly occupied the plots and reached a similar level as the control in 6 months, and this pattern was consistent at all water depths. This unbalanced speed of recovery caused higher macroalgae establishment than soft corals in treatment compared to control plots, indicating a possible phase shift in the community structure. This study provides an important implication for the necessity of monitoring the influence of disturbance at a larger scale, from a conservation perspective of soft corals in Jeju coast.

• Korean Journal of Environmental Biology
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• v.41 no.1
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• pp.54-59
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• 2023

Lovenia elongata is a member of the family Loveniidae and is one of the most common tropical echinoids. This species has a broad distribution range in the sub- and tropical regions of the Indo-Pacific Ocean, extending from the Mozambique to the Hawaiian Islands, and from southern Japan to northern Australia. It is commonly found in subtidal areas and on coral reefs within these regions. This species was for the first time recorded from the Ulleungdo Island, Korea. This species is characterized by a teardrop-shaped test that reaches up to 5 cm in length, with a deep groove at the front and tapered at the back end. The petaloid is not obvious, and the primary spines are long and banded. This study is the first to report the newly recorded L. elongata in Korea.