• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.1
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• pp.23-30
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• 2021

To examine the optimal temperature, light intensity, and shell-type for shell-living conchocelis production, we tested the shell infiltration of free-living conchocelis fragments under various environmental conditions. Under a combination of various temperatures (10, 15, 20, 25 and 30℃) and light intensities (1, 5, 10, 20, 40, and 80 μmol m-2 s-1), the optimal infiltration conditions of the evaluated three Pyropia species were 20-25℃ and 5-80 μmol m-2 s-1 for P. yezoensis, 20-30℃ and 20-80 μmol m-2 s-1 for P. seriata, and 20-25℃ and 20-80 μmol m-2 s-1 for P. dentata. The infiltration efficiency of free-living conchocelis for different shell types was greater in Korean and Chinese oyster Crassostrea gigas shells than that in scallop Argopecten irradians and clam Meretrix lusoria shells. These results suggest that oyster shells are suitable substrates for shell-living conchocelis production. In conclusion, the present results for optimal infiltration conditions for free-living conchocelis of the three examined Pyropia species will contribute significantly to the production of stable shell-living conchocelis.

• KOMUNHWA
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• no.70
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• pp.63-88
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• 2007

The purpose of this writing is to examine the places and instruments of the dissection for deformed animal carcasses excavated in shellfish stacks of the period of the Proto-Three Kingdoms(삼한) and the Three Kingdoms(삼국). The remains were chosen, which had been excavated and finished in the analysis of the animal carcasses, and the main objects are all shells and deer, especially among Mammalia. As the result, the dissection of shells was not taken place in the habitats of the animals, but inside or around of the residence of the people. For deer, too, it was done in the public place or specific area around and inside the residence. As concerns the method of dissection for shells, for Pelecypoda(부족류), represented by Meretrix lusoria(백합), the inner meat was taken out by wrenching the shell with a kind of small knives, or by boiling, and sometimes by cracking the middle of the shell in the case of big Meretrix lusoria and Dosinorbis japonicus(떡조개). For Rapana venosa(피뿔고둥), representative of Gastropoad(배발류), the people broke the top or some parts of the body to get the inner meat or used some kind of needles and stylus to pick the inner meat out after boiling. Abalones‘ meat was attached firmly to the shell, so very sharp and proper metal instruments were used to take the meat out Relatively small-sized Reishia clavigera(대수리),Top shell(밤고둥) meats were taken out by breaking the top parts after boiling, then sucking the meats, or by picking them out by using needles and stylus in the original shape. In the case of large Mammalia like deer, in the full consideration of the point that deer itself are used in various ways, they were dissected in the order of skinning, taking out the internal organs, cutting front and rear legs, separating joint parts and meats, extracting bone-marrow by 철정, 철부, ironed hand knife in very delicate ways. It seems that skinning, and front and rear legs' cutting were taken place in the place around the residence, on the other hand joint parts' separating and bone-marrow extracting in the residence. The tools for the dissection were confirmed to be hand-knife, honed ax, hammer stone, bondstone, needles and stylus, and some other sharp instrument. They were used properly according to objects.

• The Korean Journal of Malacology
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• v.27 no.2
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• pp.131-141
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• 2011

Boring caracteristics, boring rate, and predation, rates on the valves of the seed and adult clams of Meretrix petechialis by Glossaulax didyma didyma in the shellfish aquafarm and the indoor rearing aquarium were investigated by various morphometric data. The investigations were carried out from June to September, 2007. The morphology of drilled holes on the valves of M. petechialis showed the crater type as seen in the spats of Ruditapes philippinarum and M. lusoria. The sizes of the outer diameters of holes were greater than the inner diameters of the holes on the valves of M. petechialis in the shellfish aquafarm and the indoor aquarium at the laboratory. On the whole, the sizes of the holes on the valves of the seeds of M. petechialis was smaller than those bored holes on the adult valves. The location of the bored holes on the valves of the seeds varied widely with the the sizes of the individuals of M. petichialis, while most of holes on the valves of adult clams were located near the umbo position of the valves of the clams in the shellfish aquafarm and the indoor aquarium at the laboratory. On the whole, the outer and inner diameters of the bored holes increased with increase of shell lengths of the clams in the shellfish aquafarm and the indoor rearing aquarium at the laboratory. The authors could confirm experimentally the boring snail, G. didyma didyma, drilled the seeds and adult clams of M. petechialis. In the experiments for 15 days (three times repeated) in the indoor rearing aquarium at the laboratory, the mortality of dead shells to total shells of M. petechialis by boring snail Glossaulax didyma didyma was totally average 41.5%, and percent of drilled shells to total dead shells of clams by the boring snail was average 47.1%. Of total shells, percent of drilled shells to total shells of clams by the boring snail was totally average 19.3%. Predation of G. didyma didyma were greater at night than the day time. Average 0.5 seed and adult individuals of M. petewchialis were consumed per G. didyma didyma, per day. Predation varied with shell lengths of M. petechialis and shell widths of G. didyma didyma.

• The Korean Journal of Malacology
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• v.27 no.2
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• pp.115-119
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• 2011

To establish technical development for artificial seed production, growth and survival for early young spats of the hard clam, Meretrix petechialis, were investigated by breeding methods. Adult clams were collected at Hasa-ri, Baeksu-eup, Yeonggwang-gun, Jeollanam-do on July 13, 2010, and then transported to the indoor aquarium at the laboratory. Eggs which were taken from mother clams, were inseminated, and after they were fertilized in the aquarium, 60 million bottom-clinging spats ($198{\pm}12{\mu}m$ in shell length) were produced and bred. The breeding experiments were carried out from July 16 to October 4, 2010 for 80 days. The methods of sand box, sand bottom circulation filter, inclosing net, floor were used for the breeding experiments, and the experimental condition of sea water temperature for larvae were at 25, 28, 31, $34^{\circ}C$. Four marine cultured food organisms were used for this study as follows: Isochrysis galbana, Chaetoceros gracilis, Phaeodactylum tricornutum, Tetraselmis tetrathele. According to the experimental conditions, experimental groups of the spats in the early stage were investigated the growth rate and the survival. As the result, the method of the inclosing net section was the fastest (grew up to $2.64{\pm}0.59{\mu}m$ in shell length), followed by sandbox ($2.59{\pm}0.64{\mu}m$, bottom circulating filter ($2.56{\pm}0.52{\mu}m$), and floor ($2.52{\pm}0.56{\mu}m$). The survival was the highest in the experimental condition of sandbox (35.9%), followed by floor (34.6%), bottom circulating filter (29.5%), and inclosing net (9.3%). Eexperimental condition of water temperature of $34^{\circ}C$ showed the fastest growth rate (grew up to $2.70{\pm}0.76{\mu}m$ in shell length), and showed the latest growth rate (grew up to $2.45{\pm}0.41{\mu}m$ in shell length) at $25^{\circ}C$. The survival (%) was the highest under the water temperature conditions at $31^{\circ}C$, and showed the lowest (14.2%) at $34.^{\circ}C$. The growth rate of the experimental group fed the mixture live food was the fastest with shell length $2.52{\pm}0.66{\mu}m$, and that of experimental group fed P. tricornutum showed the latest (grew up to $2.29{\pm}0.43{\mu}m$ in shell length). The survival was the highest (36.9%) under the experiment condition fed mixture live food and experimental group fed T. tetrathele showed the lowest rate (16.2%).

• The Korean Journal of Malacology
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• v.31 no.4
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• pp.279-283
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• 2015

This study investigated spectroscopic characteristics of shell crystals of eight marine bivalve species using X-ray diffraction (XRD) analysis; moreover, the Family level relatedness of shellfish was investigated. In XRD analysis, the shells of Ruditapes philippinarum, Meretrix lusoria, Anadara granosa, and Fulvia mutica were found to have orthorhombic aragonite $CaCO_3$ crystals, while shells of Patinopecten yessoensis and Crassostrea gigas had trigonal-rhombohedral calcite crystals. The shells of Mytilus coruscus and Atrina pectinata were determined to have a mixture of aragonite and calcite crystals. XRD information revealed the Family level-specific characteristics of shellfish; the results agreed with the current taxonomic system. In conclusion, spectroscopic characteristics of shell crystals indicated Family-level characteristics of shellfish and suggested a more intense species-level investigation; this technology may be useful in identifying shellfish species using small quantities of shells.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.2 no.1
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• pp.33-40
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• 1969

1. Physicochemical properties of sea water and soil of Korean tidal flats densely populated with species of Mactra veneriformis, Cyclina sinensis, Meretrix lusoria, and Tapes philippinarum, were investigated in order to find out the index of environmental factors in marine bivalve culture. 2. The turbidity varied with the change in concentrations of organic matter, silicate, and the exchangeable copper in sea water. All of these concentrations in Inchon, Kunsan, and Hansando were higher than those in Yusoo. In the 5 areas investigated the lowest were ditected at Kangnung. 3. The minerals and organic matter content in sea water dia not vary significantly among the different bivalve beds. And it was presumed that the soil texture was one of the most important environmental factors for the density of the bivalves in tidelands. 4. The soil texture index of the different bivalve beds was obtained as follow: 5. There were no significant differences of pH, the exchangeable calcium, and the exchangeable copper contents of bottom soils in the 4 different bivalve beds. As important factors in these areas, it seems that the amount of chemical properties might not affect the distribution of bivalve species. 6. Among the 4 beds the soil organic matter content was highest at the T. philippinarum bed and varied with the total nitrogen content. 7. Among the different bivalve beds, it was significant that the water holding capacity and available phosphorus content were highest at the M. veneriformis bed.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.206-212
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• 1998

This study was undertaken to explore the applicability of glutathione S-transferase (GST) activity as a predictable indicator to monitor chemical pollution in shells and fishes utilized for food. There were some variations in the basal level of GST activity depending on species tested. Ark shells, Anadara satowi, showed the highest normal enzyme activity, followed by catfish and marine mussels, Mytilus coruscus. White clams, Meretrix lusoria, Israeli carp and catfish had lower activity. When A. satowi was exposed to 3-methyl-cholanthrene (3-MC), a prototypic polycyclic aromatic hydrocarbon for 1 week, GST activity decreased by about 30%. This reduction in GST activity induced by 3-MC did not recover until two weeks after the cessation of exposure. GST activity increased in response to 3-MC in most of the other species studied. The GST elevation in M. coruscus attained its maxinum of about 200% at the termination of 3-MC exposure maintaining this level up to 2 weeks, and declined gradually thereafter. 3-MC also induced GST activity in lsraeli carp in a similar fashion to M. coruscus. Phenobarbital induced GST activity both in M. coruscus and lsraeil carp. Other chemicals. such as clofibrate, butylated hydroxyanisole. hexachlorobenzene, and oxolinic acid did not change the enzyme activity significantly in most speciel. Phenol depressed GST activity only in lsraeli carp. These results suggest that the basal level of GST activity is somewhat variable and that the direction of change in response to chemicals seems to be related to its normal activity. The change in enzyme activity can be a preditable indicator of some environmental chemicals such as PAHs and phenol.

• Applied Biological Chemistry
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• v.19 no.2
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• pp.112-119
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• 1976

The appearance of organochlorine pesticide residues in water, mud and clam (Meretrix lusoria) samples from the lower basin of Seomjin River around the Kwangyang Bay was surveyed to obtain the following results. 1) The concentrations of pesticide residues in the water samples were found to be in the order of dieldrin> aldrin>${\alpha}-BHC$> ${\gamma}-BHC$> endrin> heptachlor> heptachlor epoxide and in the range of $0-48ng/{\ell}$. 2) The concentrations of pesticide residues in the mud samples were found to be in the order of aldrin> dieldrin>${\alpha}-BHC$> ${\gamma}-BHC$> heptachlor> heptachlor epoxide> endrin, ranging $0-10\;{\mu}g/kg$ (dry matter), and to be more in lower layer than in upper layer. 3) The concentrations of pesticide residues in the clam samples were found to be in the of order heptachlor> ${\gamma}-BHC$> ${\alpha}-BHC$> aldrin> heptachlor epoxide> dieldrin> endrin and in the range of $0.1-18\;{\mu}g/kg$ (edible fresh muscle). The level reached the highest in 3-year old clams and sharply deceased thereafter.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.922-934
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• 2000

To investigate the composition of carotenoids present in marine organisms and the biological activity of the carotenoids, carotenoids of the muscles and tunic of tunicates and shellfishes were isolated and identified. Anitmutagenic activities of the carotenoids for S. typhimurium TA 98 and cytotoxic activity for cancer cell lines were determined. Total carotenoid contents in the muscle of tunicata ranged from 18.65 mg% to 2.39 mg%. The highest amount of the total carotenoid was found in the muscle of Halocynthia aurantium, followed by Styela clava (HERDMAN), H. roretzi, H. hilgendorfi f. igaboya, H. hilgendorfi f. retteri, S. plicata (LESUEUR) in order. Interestingly, total carotenoid content in the muscle of S. clava (HERDAMAN) was higher than that of H. roretzi. Total carotenoid content of all tunicata, other than H. aurantium and H. roretzi, were higher in muscle than tunic. The major carotenoids in H. roretzi, H. aurantium, S. plicata (LESUEUR), and S. clava (HERDAMAN) were cynthiaxanthin (25.1∼42.2%), halocynthiaxanthin (9.7∼26.3%), diatoxanthin (8.0∼18.7%) and β-carotene (7.7%∼21.7%). Similarly, cantaxanthin (19.6%), cynthiaxanthin (15.4%), halocynthiaxanthin (14.8%), and (3R, 3'R), (3S, 3'S)-astaxanthin (22.6%) in H. hilgendorfi f. retteri and fucoxanthin (26.6%), cynthiaxanthin (21.8%), halocynthiaxanthin (15.2%), and β-carotene (9.3%) in H. hilgendorfi f. igaboya were major carotenoids in both tunicate. However, the composition of carotenoids in muscle and tunic of tunicata was similar each other. Among the shellfishes examined, total carotenoid content of the muscle of Peronidia venulosa (Schrenck) and Corbicula fluminea, and of the gonad of Atrina pinnata and Chlamys farreri, was ranged from 2.51 to 6.83 mg% which were relatively higher than that of other shellfishes. The composition of the carotenoids of shellfishes, which might depend upon their living environments, was varied. But cynthiaxanthin (15.9∼39.0%) and zeaxanthin (9.6∼21.9%) in gonad of C. farreri, and muscles of Buccinum Volutharpa perryi (JAY) and Crassostrea gigas, cynthiaxanthin (21.5∼48.6%) and mytiloxanthin (14.6%) in muscle of C.fluminea and gonad of A. pinnata, and canthaxanthin (60.6%) and isozeaxanthin (20.5%) in muscles of P. venulosa (Schrenck), and β-carotene (23.7%∼37.8%) and zeaxanthin (18.2∼20.4) in muscles of Semisulcospira libertina and Meretrix lusoria were major carotenoids. Interestingly, diester type-carotenoids were present along with free type-carotenoids in muscles of C. gigas. antimutagenic effect of the carotenoids isolated from tunicata and shellfishes against 2-amino-3-methylimidazol [4,5-f]quinoline (IQ) for S. typhimurium TA 98 was proportional to the amount (20, 50 and 100㎍/plate) treated. Mutagenicity of IQ was significantly reduced by astaxanthin, isozeaxanthin, mytiloxanthin and halocynthiaxanthin, whereas the mutagenicity of aflatoxin B₁(AFB₁) was significantly reduced by β-carotene, isozeaxanthin, and mytiloxnthin. Growth inhibition effect of carotenoids isolated from tunicata and shellfishes for cancer cell was proportional to the amount (5, 10, and 20㎍/plate) treated. The growth of HeLa cell by β-carotene, cynthiaxanthin, astaxanthin and halocynthiaxanthin, NCI-H87 cell by β-carotene, astaxanthin, cynthiaxanthin, and halocynthiaxanthin, HT-29 cell by β-carotene, cynthiaxanthin, mytiloxanthin and halocynthiaxanthin, and MG-63 cells by β-carotene, cynthiaxanthin, astaxanthin, canthaxanthin and halocynthiaxanthin were statistically reduced.

• Journal of Food Hygiene and Safety
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• v.3 no.1
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• pp.7-18
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• 1988

In 1987, the level of heavy metals were determined ina total of 200 samples of 9 species of shellfish of Korea. The samples were collected at the fish. markets by 10 Public Institute of Health. The samples were whelk (Buccinum striatiBBimum), oyster (Crassostrea gigas), ark shell(Tegillarca granesa), shartnecked clam (Venerupis semidecussta), hard clam (Meretrix lusoria), top shell (Turbo cornutus), abalone (Haliotis gigantea), ark shell (Scapharea broughtonii), sea-mussel (Mytilus conuscus gould), respectively. The levels of total mercury, lead, cadmium, arsenic, copper, zinc and manganese were determined. The total mercury levels were determined by mercury analyzer using the combustion gold amalgamation method. The arsenic level were determined by spectrophotometry using colorimetric sil ver diethyldithiocarbamate method after dry ash dige8tion of the samples with magnesium oxide and magnesium nitrate. The levels of other metals were determined by inductively coupled pluma spectrophotometry after wet digestion of the samples with nitric acid and su1furic acid. The results were summerized as follows; 1. The overallranges and mean(ppm) were; Hg, ND-O.221 (0.036); Pb, 0.05-1.51 (0.37); Cd, 0.02-1.86 (0.61); As, 0.5-3.97 (1.22); Cu, 0.14-54.16 (4.93); Zn, 7.40-207.17 (30.09); Mn, 0.13-s.72 (3.40). 2. The levels of all 6 metals were found to be below the maximum permissible Iimits set by the Japan lor mercury, the Netherland for lead the Hong Kong for cadmium. The Finland for Arsenic no statutory Iimits for Zn and Mn in shellfish in any countries. 3. The results show that all the 9 species of shellfish studied, none have accumulated levels dangerous enough to pose a health problem.roblem.