• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.6
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• pp.647-655
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• 2018

This study collected basic data on two types of canned roasted oyster Crassostrea gigas. Oysters Crassostrea gigas were immersed at $105^{\circ}C$ for 6 min and then washed and dehydrated before pre-drying. Roasted oysters were prepared by baking boiled oysters at $140^{\circ}C$ for 20 min. The canned roasted oyster added with tomato sauce was prepared as follows. An aluminum can was filled with 50 g of roasted oyster and 40 g of mixed seasoning sauce, degassed at $90^{\circ}C$ for 3 min and vacuum-sealed using a double seamer under a 20 cmHg vacuum. The canned roasted oyster added with tomato paste sauce was prepared similarly by adding the same amount of tomato paste sauce instead of tomato sauce. Microbial growth, appearance, proximate composition, pH, volatile basic nitrogen (VBN), thiobarbituric acid (TBA) value, amino-N, salinity, color value, texture, free and total amino acids, and minerals were measured in the two products. A sensory evaluation indicated that the canned roasted oyster added with tomato paste sauce had preferable characteristics over the canned roasted oyster sauce added with tomato sauce.

• Fisheries and Aquatic Sciences
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• v.11 no.1
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• pp.32-35
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• 2008

The Suminoe oyster, Crassostrea ariakensis, occurs in estuaries where rivers meet seawater. In Korea, it is one of the most popular fisheries resources in the Nam River and Sumjin River. However, the genetic identification of this species has been questioned, because specimens are often mis-identified as other species. To identify the species, we conducted polymerase chain reaction (PCR) amplification of the internal transcribed spacer-1 (ITS-1) region, followed by digestion with the restriction enzyme HaeIII. Restriction profiles for oysters collected from Korea, Japan, and China (north and south) were determined by comparing the PCR-restriction fragment length polymorphism (RFLP) patterns of the ITS-1 regions. Our study verified that the oysters collected from Korea were C. ariakensis based on the PCR-RFLP patterns. These results emphasize the value of molecular markers for identifying morphologically uncertain species.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.5
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• pp.1075-1082
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• 2014

Monthly Screening of Pacific oyster, Crassostrea gigas, was surveyed by PCR for Ostreid herpesvirus(OsHV-1) infections from 2012 to 2013 in Korea. It was showed positive results in one hatchery in April and May 2012 and in oyster farming areas from August to November in 2013. The obtained sequences showed 99.3~99.5% homology with OsHV-1 ${\mu}var$(Accession Number: HQ842610) and 96.2~96.3% homology with OsHV isolated from Korea(Accession Number: AY509253).

• Fisheries and Aquatic Sciences
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• v.6 no.4
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• pp.220-224
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• 2003

In order to determined the appropriate processing season of Pacific oyster (Crassostrea gigas), 30 individuals cultured in Kamak Bay on the southern coast of Korea were taken bimonthly 7 times a year, and seasonal variation of edible portion weight, edible portion yield and coefficient of fatness were investigated. There were close relationships between edible portion weight (X) and total weight (Y) and between coefficient of fatness (X) and edible portion yield (Y), which were expressed in regression lines, i.e. Y=0.2709X-1.9094 (r=0.9254) and Y=44.0596X+ 15.1127 (r=0.8485), respectively. From the results of seasonal variation of edible portion weight, yield and coefficient of fatness, the appropriate processing season of raw Pacific oyster was between winter and spring, that is, between December and following April the next year.

• The Korean Journal of Malacology
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• v.27 no.3
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• pp.223-228
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• 2011

To understand the role of hemocytes in the shell repair process, a hole was drilled in the right valves of the Pacific oyster, Crassostrea gigas, and the repair process was observed. Histological observations suggested that the exterior surface of the shell was repaired by aggregated hemocytes. The nuclei of the hemocytes were cleary stained in the regenerated shell while appearing fragmented after calcification at the $7^{th}$ day. Globular calcium granules were genegenerated from the hemocytic monolyer after 6 days of incubation which were morphologically and chemically identical with those from prismatic shell. Our finding suggested that the repaired prismatic shell was composed by aggregated hemocytes and that their endogenous calcium component might support the nucleation of calcium biomineralization during shell repair.

• Fisheries and Aquatic Sciences
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• v.6 no.3
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• pp.135-139
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• 2003

During routine survey of Pacific oyster (Crassostrea gigas) collected from Tongyoung area in southern coast of Korea, histological examination revealed that a intracellular microorganisms infected the digestive gland of the oyster. They infected hepatopancreatic cells extensively. The size of intracellular microorganism was of 45 to 86nm in diameter and 200nm to more thar 500nm in length. They were pleomorphic. The morphological characteristic of intracellular microorganisms lacked cell wall and was bounded by the plasma membrane. They contained typical prokaryotic ribosomes and fibrillar DNA-like strands. No additional internal structure has been observed. Based on the lack of cell wall and the cellular localization, the intracellular microorganism is considered as a Mycoplasma-like organism.

• The Korean Journal of Malacology
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• v.27 no.1
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• pp.35-42
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• 2011

In order to understand effect of polycyclic aromatic hydrocarbon (PAH) on shell repair of the Pacific oyster, Crassostrea gigas, shell regeneration experiments were carried out using oysters drilled a hole on the right valve. The change of pH and hemocytic characteristics in both extrapallial fluid and hemolymph were observed during the shell repair. The thickness of mantle tissue was apparently decreased, while necrosis in epithelium and periostracal gland was increased in response to PAH exposure. Our finding suggested that PAH could adversely influence on shell repair.

• Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.15-19
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• 2012

A new cyclic peptide (six-membered amino acid), gamakamide-E (L-Leu-L-Met (SO)-L-Me-Phe-L-Leu-D-Lys-L-Phe), was isolated as a strongly bitter tasting compound from cultured oysters, Crassostrea gigas. The molecular formula of $C_{43}H_{61}N_7O_8S$ was deduced from high resolution fast atom bombardment mass spectrometry (HR FAB-MS) ($[M+H]^+$ m/z 836.4356 ${\Delta}$= -2.4 mmu). Its unique structure including a hydantoin structure was firstly elucidated by nuclear magnetic resonance (NMR) analysis. Stereochemistries of constituent amino acids were determined by chiral high performanced liquid chromatography analysis of natural and synthesized peptides.

• Journal of Environmental Health Sciences
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• v.9 no.1
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• pp.63-76
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• 1983

중금속은 해수에서보다 해수중의 생물계에 그 농도가 더 높은 것으로 알려져 있으며 수은도 무기형으로 생물계에 존재하다가 생물활동으로 인해 알킬형으로 변한다. food chain이 미량금속 축적의 주통로로 알려져 있으나 그외 몇가지 방법이 제시되고 잇다. 특히 연체동물은 미량금속의 축적현상이 온도, 폭로시간, 시간, 생리적 활동에 다라 상당히 달라진다. 또한 유기알킬 수은이 무기수은보다 비교적 낮은 독성을 나타내지만 후자의 피해도 무시할 수는 없다. 굴(crassostrea virginica)은 염화수은농도가 비교적 낮은 상태에서도 상\ulcorner량의 축적현상을 보여주었다. 두개의 compartment system을 연계적인 상태에서 보면 첫 compartment에서의 초기축적은 가역적이었으나 둘째 Compartment에서 측정된 원실율로 보아 비가역적 축적이상을 확인해 주었다. 뿐만 아니라 미량금속이 아가미와 외부 근육에서 가장 높은 축적률을 보인것은 flow system의 regression moder과 매우 흡사함을 암시하며 농도가 낮은 상태에서의 축적이상에 중요한 의미를 부여하였다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.193-194
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• 2002

Angiotensin I converting enzyme (ACE) inhibitor was purified from Crassostrea gigas. The ACE belongs to the class of metalloprotease. This enzyme plays an important physiological role in regulating blood pressure of the rennin-angiotensin system by converting from angiotensin I to octapeptide angiotensin II, a potent vasoconstrictor and by inactivating bradykinin, which has depressor action. (omitted)