• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.31 no.5
• /
• pp.637-644
• /
• 1998

[ $\beta$ ]-Galactosidase was extracted from the internal organ of sea urchin, Hemicentrotus pulcherrimus The enzyme was purified 384.6-fold over the crude extract by the sequential chromatographic methods including DEAE-Sephadex A-25, CM-Cellulose, and Con A-Sepharose 4B affinity chromatography with a recovery $1.26\%$. The molecular weight of the purified enzyme was estimated approximately 94 kDa as monomeric term by SDS-PAGE and Sephadex G-150 gel chromatography. The maximum enzymatic activity was observed at pH 3.0 and $50^{\circ}C$ but the one was stable over the ph range or 3.0$\~$5.0 and below $37^{\circ}C$. The $K_m$ and $V_{max}$ values against PNPG (P-nitrophenyl $\beta$-D-galactopyranoside) were 15.0 mM and 214 $\mu$mole/min per mg protein, respectively. The enzymatic activity was activated by $Ba^{2+}$, but significantly inhibited by $DEP,\;Hg^{2+},\;Sn^{2+}$ and galactose.

• Journal of Aquaculture
• /
• v.13 no.2
• /
• pp.129-135
• /
• 2000

Genetic variabilities of local populations of Anthocidaris crassispina and Hemicentrotus pulcherrimus were analysed by random amplified polymorphic DNA (RAPD) technique with phenotypic variabilities in timing of gonadal maturation, reproductive output and size of individuals in Cheju. H, pulcherrimus, collected from 4 locations during March 1997, indicated that Daepo individuals were significantly smaller than that at Hamdok, Wimi site A and Wimi site B (ANOVA, p>0.001). Gonodal-somatic index (GSI) of the Wimi site B population was significantly higher than that of three other locations (ANOVA, P>0.0001). An ANOVA test conducted on test size of A. crassispina, harvested from six different locations of Cheju during June 1997, indicated that the size of individuals from Pophwan was significantly smaller (P>0.0001) than that from five other locations. GSIs of urchin m Wimi and Hanlim were significantly higher than that from Pohwan and Oedo (ANOVA, p>0.0001). Genetic similarity, calculated from k13 primer analysis of total DNA, among the six different populations of A. crassispina varied from 0.67 to 0.92, and the values for H. pulcherrimus from 0.60 to 0.73; thus there was no genetic variation among different populations of the same species. Therefore, the populations are genetically homologous and the observed phenotypic variabilities were possibly associated with water temperature and food.

• Animal Systematics, Evolution and Diversity
• /
• v.11 no.1
• /
• pp.115-124
• /
• 1995

Twenty-two species of Echinodermata collected from 11 localities in Chindo Island, Korea in September, 1990 and July, 1994 are recorded. One asteroids, Luidia quinaria, five ophiudoids such as Astrocladus coniferus coniferus, A.c.dofleini, Ophicatis affinis, Stegophiura sladeni, Amphipholis sp., four echinoids such as Temnopleurus toreumaticus, T. hardwicki, Hemicentrotus pulcherrimus, anthoicidaris crassispina and two holothuroids such as Protankyra bidentata, Stichopus japonicus are unrecorded species by this time in Chindo Is. One asteroid species, Asterina minor is newly recorded in Korea water and its taxonomic characteristics are redescribed.

• Journal of Aquaculture
• /
• v.11 no.3
• /
• pp.401-419
• /
• 1998

The structure of benthic algal flora and feeding behavior of sea urchins (Anthocidaris crassispina and Hemicentrotus pulcherrimus), were investigated from the eight different locations along the coast of Cheju Island, Korea. Biomass distribution and dominance of the algal communities were studied in relation to the gut contents and population parameters of the sea urchins. As a result, although the largest algal biomass and biological characteristics of sea urchins, such as test diameter, test hight, body weight, gonad weight, etc. This inhdicated that sea urchins would not be dependednt sorely on the abundance of algal foods, and they might feed on other food items. In order to know such a trend with regard to food selectivity, the diets consumed by sea urchins were analyzed, and it was found that they were composed of benthic and drifted algae, various animal components (sponges, bryozoans, crustaceans, and various unidentified capsulated eggs, etc.) and biets turned out to be smaller than might be expected, and it is postulated that sea urchins were not likely to be the major grazing animals for the formation of algal bed and also canopy deterioration, so-called "white incrustation."

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.17 no.5
• /
• pp.414-422
• /
• 1984

This research was conducted to evaluate the effect of polluted Oncheon Stream on the marine organisms in the Suyeong Bay. Water quality and 96 hr acute toxicity to the sea urchin, Hemicentrotns pulcherrimus by recirculation bioassay were examined from Feb. 20 to Apr. 15, 1984. The 96 hr $50\%$ effective concentration($EC_{50}$) on the attachment of the podia of the sea urchin was observed to occur at test concentrations between 40.0 and $51.0\%$ (v/v), and safe concentrations may be assumed to be within 4.0 and $5.1\%$. These values indicate as follows : 1. Oncheon Stream was extremely polluted by oxygen-demanding wastes and synthetic organic compounds from sewage and industrial waste water. 2. Linear alkylbenzene sulfonate(LAS) which has not been yet included in water quality standard was discharged above the TLm. 3. Unknown toxicity may be synergy among complex substances. In consideration of the relationship between COD values of Oncheon Stream and dilution water, the effect of toxicity of Oncheon Stream water reached to the area of the Suyeong Bay where the COD value was found to be 12.2 ppm.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.38 no.2
• /
• pp.100-105
• /
• 2005

Two species of fish and five species of marine invertebrate showed different tolerances to the toxicity of composite slag and bituminaus coal. Especially, Hemicentrotus pulcherrimus and young Haliotis discus hannai displayed marked differences in tolerance from. H. pulcherrimus and young H. discus hannai showed lethal effects at higher concentrations than those concentrations of the composite slag in the 1.0 and $0.4\%$ range, respectively. H. pulcherrimus showed no lethal effects at a lower concentration of $1.0\%$ composite slag and some differences in the rate of oxygen consumption with this concentration of composite slag. The lethal effects of bituminous coal on marine and fisheries organisms, even with higher concentrations, were not observed. At a higher concentration than that of 500 mg/L (ppm) of bituminous coal, decrease effects appeared in the rate of oxygen consumption of the experimental organisms. Taking into consideration that the experimental concentration of composite slag and bituminous coal were impracticable in the ocean, the results of this experiment suggest that composite slag and bituminous coal pose no real threat to marine or fisheries organisms.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.3 no.3
• /
• pp.170-174
• /
• 1998

The water quality of offshore waters around the Korean coast was evaluated by bioassay using gametes, embryoss and early development systems of a sea urchin species Hemicentrotus pulcherrimus. The results show that despite the inflows of several river systems, the west coast maintain the grade II water. This is thought to be due to the decrease in pollutant input resulting from the purification of inflow rivers (e.g., the control of waste water discharge and the construction of sewage treatment facilities), and the dilution of pollutants by a strong tidal mixing with a large difference between the ebb and flood tides. However, Asan, Hampyong and Chonsu bays, where circulations of water are relatively poor, and the Kunsan and Mokpo harbors which are influenced by pollutants from neighboring cities have shown the grade III water. The south coast has maintain the grade II or III because developments of sea urchins were moderately or strongly inhibited. Also, Kangjin, Duekryang, Kwangyang, Masan, and Jinhae bays where water circulations are relatively poor, show the grade III water, with strong inhibitions of the early development of sea urchins. The east coast has maintained the grade I and II due to monotonous coastlines and smooth circulation of sea water. However, Chongcho Lake shows the worst water quality due to the breakwater which is constructed to maintain port functions.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.22 no.3
• /
• pp.291-299
• /
• 1993

The lipid components of the gonad of sea urchin Hemicentrotus pulcherrimus, ark shell Scapharca bro-ughtonii and "Gaebul" (Korea name, a worm) Urechis unicinctus were investigated. The total lipid (TL) contents of the sea urchin, the ark shell and the "Gaebul" were 6.10, 0.67 and 0.79%, respectively. The percentages of phospholipid (PL) in TL were higher in the "Gaebul"(72.4%) and ark shell(64.9%) compared to the sea urchin (41.7%). The major lipid classes of PL were phosphatidylcholine and phosphatidylethanolamine, and the former was rich in the sea urchin (56.2%) and the latter in the "Gaebul"(34.4%). In the class of non-polar lipid (NL), the major lipid classes were different from species ; the sea urchin was rich in triglyceride(TG, 89.0%), the ark shell rich in TG (69.2%) and cholesterol (ST 26.8%) and the "Gaebul"rich in ST (70.7%). The prominent fatty acids of the sea urchin were 16 : 0, 14 : 0, 20 : 5n-3, 20 : 4n-6 and 20 : 4n-6 and 20 : 2NMID(non-methylene interupted dien). The percentage of 20 : 4n-6 was the highest of the investigated invertebrates, accounting for 19.8% in PL, but 22 : 6n-3 was not detected in the sea urchin. In case of the ark shell, the prominent fatty acids were 16 : 0, 18 : 0, 20 : 5n-3, 22 : 6n-3 and 22 : 2NMID, especially 22 : 6n-3(9.58%) was richer compared to that of the "Gaebul". The prominent fatty acids of the "Gaebul"were 20 : 5n-3, 16 : 0, 18 : 0 20 : 1n-9, 16 : 1n-7 and 14 : 0. The percentage of 20 : 5n-3 (22.0%) was highest in the PL of the "Gaebul"among the three invertebrates. These differences in the lipid components of all the sample is considered to be due to the different food habits and environmental condition of the invertebrates.

• Journal of Aquaculture
• /
• v.21 no.3
• /
• pp.139-145
• /
• 2008

Morphological classification of echinoid species has many difficulties because of their phenotypic variations. In the present study, we analyzed morphotypes and partial mitochondrial 12S rDNA sequences of four sea urchin species classified as Pseudocentrotus depressus, Anthocidaris crassispina, Hemicentrotus pulcherrimus and Strongylocentrotus nudus, and unidentified four species collected from the coasts of the East sea. Their genomic DNAs were extracted from gonads and mitochondrial 12S rDNA sequences were amplified by the polymerase chain reaction (PCR) method. The sequence identities among the known four sea urchin species were 87.4-95.6%. The sequence identities among the unidentified four species were 99.4-99.6% and showed the highest homology to S. intermedius(99.8%). Thus, our phylogenetic tree indicates that the unidentified four species belong to S. intermedius.

• Journal of Aquaculture
• /
• v.11 no.4
• /
• pp.437-447
• /
• 1998

In mass production of larval rockfish, Sebastes schlegeli, high mortality had been observed frequently. This may be the consequence of the low nutritional quality of the live feeds used. This experiment was designed to find out a suitable diet for the mass production of rockfish larvae. Three kinds of live feeds were tested ; plutei of sea urchin (Hemicentrotus pulcherrimus), L-type rotifers (Brachionus plicatiilis) and Artemia naupii. The latter two were enriched with ${\omega}$-yeast, Spirulina platensis and Super Selco before feeding to rockfish larvae. The sea urchin plutei caused to poor survival and growth rates for larval rockfish, and therefore, they were not seemed as proper feed for rockfish larvae. Enrichments of rotifers and Artemia nauplii with ${\omega}$-yeast, Spirulina platensis, or Super Selco improved survival and growth rate. But, rotifers enriched with Super Selco resulted in better rockfish larvae survival than those enriched with ${\omega}$-yeast. A sudden increase of mortality occurred around 11 days after birth. In this critical period, a shift feed such as Artemia nauplii had been supplemented with rotifers. After this critical transition period, the moratality gradually decreased by feeding Artemia nauplii enriched with PUFA. Feeding of mixed feed with rotifers and Artemia nauplii resulted in better larval survival and growth than those of each live food alone.