• Food Science and Biotechnology
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• 제18권4호
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• pp.842-848
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• 2009

The purpose of this study was to determine the extent of domoic acid (DA) a potent neurotoxin, responsible for the syndrome amnesic shellfish poisoning (ASP) contamination of various species of bivalve shellfish purchased from fish market in Korea and the implications for food safety. Liquid chromatography (LC) methods were applied to quantify DA in shellfish after sample clean-up using solid-phase extraction (SPE) with strong anion exchange (SAX) cartridges. Toxin detection was achieved using photodiode array ultraviolet (LC-UV) and electrospray ionization-mass (LC-ESI-MS). DA was identified in 4 bivalve shellfishes of 872 shellfishes collected from March, 2006 to October, 2007 in Korea. DA amount of 3 surf clams (Mactra veneriformis) collected at Seoul, Daejeon, and Daegu were 4.13, 1.99, and 1.94 mg/kg, respectively. DA amount of 1 pink butterfly shell (Peronidia venulosa) collected at Seoul was 3.02 mg DA/kg. The amounts of DA that were present in 4 bivalve shellfishes were within EU guideline limits for sale of shellfish (20 mg DA/kg).

• Fisheries and Aquatic Sciences
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• 제14권3호
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• pp.226-229
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• 2011

This study was conducted to develop a proficiency test (PT) specimen for the enumeration of Escherichia coli, a sanitary indicative bacterium, in molluscan bivalve shellfish. The common mussel Mytilus edulis was chosen as a matrix for the PT specimen. Mussels were artificially bioaccumulated for approximately 3 h with E. coli culture. After determining the homogeneity of samples, samples were distributed to 17 participants involved in the proficiency testing program. The enumeration of E. coli was performed by the most probable number method of the American Public Health Association. Statistical evaluations of the results obtained from inter- and intra-laboratory variation indicated no significant differences in the accuracy of these techniques between participants, indicating z-scores of ${\leq}{\pm}2$ and suggesting that preparation of the PT specimen for enumerating E coli in shellfish was successful.

• 한국식품위생안전성학회지
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• 제15권4호
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• pp.293-296
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• 2000

마비성패류독에 의하여 독화된 패류의 활용 방안 모색과 제독 방법 구명을 위하여 1997년 1월부터 12월까지 경남 진해만산 이매패류의 마비성패류독에 의한 독화 경향과 각각의 패류 종에 축적된 독소 구성성분 특성을 조사한 결과는 다음과 같다. 진해만 해역에서의 마비성패류독에 의한 이매패류 독화는 2월부터 시작하여 4월 중순에 최성기에 도달한 후 점차 감소하여 6월에는 완전히 소멸되었으며, 주요 양식 대상 품종인 진주담치와 굴 중의 마비성패류독이 식품에서의 허용기준치 (80$\mu\textrm{g}$/100g) 이상 지속되었던 기간은 각각 2개월과 40일이었다. 패류 종에 따른 마비성패류독에 의한 독화의 정도는 진주담치가 가장 높았으며, 바지락,굴, 피조개의 순이었다. 독소 출현 최성기인 4월 중순에서의 진주담치 독화의 정도는 굴의 6배에 달하였다. 독화된 진주담치와 굴의 경우 최고 독력 3,351 및 574$\mu\textrm{g}$/100g에서 50%수준으로 자연 감소하는데는 각각 15일과 7일이 소요되었으며, 기준치 이하로 감소하는데는 각각 1개월과 20일이 소요되었다. 패류의 체내에 축적된 마비성패류독의 구성성분은 진주담치, 바지락, 피조개, 그리고 왕우럭에서는 GTX1~4 group이 59.0~78.8%로 절대 우점을 차지하였으며, 검출 독성도 대부분 GTX group에 의한 것이었다. 그러나 굴의 경우 Cl과 neoSTX가 각각 37.9%, 26.2%를 차지하였으나 Cl에 의한 독성은 거의 없었으며, 검출 독성의 대부분 (80.0%)이 STX group에 의한 것으로 확인되었다.

• 한국수산과학회지
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• 제52권1호
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• pp.27-34
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• 2019

The seasonal and spatial variation of pathogenic Vibrio species, such as V. parahaemolyticus, V. vulnificus, V. alginolyticus, and V. cholerae were investigated in seawater and in bivalves off the Gyeongnam coast of Korea, which is an important area for shellfish production, during the period 2013-2016. V. parahaemolyticus, V. vulnificus, V. alginolyticus, and V. cholerae were detected in 12.1%, 5.2%, 15.4%, and 0.9% of seawater samples, respectively. V. parahaemolyticus, V. vulnificus, V. alginolyticus, and V. cholera were detected in 21.9%, 7.1%, 12.2%, and 0.0% of shellfish samples, respectively. The Vibrio spp. in seawater and bivalve samples were detected at high levels during the summer to early autumn; however, the levels were low during the winter. Therefore, their occurrence was seasonally dependent and correlated with high water temperature, which is also the biggest factor contributing to foodborne outbreaks associated with Vibrio. Relatively high detection rates of the strains were also found in the sea area that was continually exposed to inland wastewater. Our findings show that continuous monitoring is needed to reveal the patterns of occurrence of these pathogens from marine samples collected off the Korean coast, to reduce seafood-borne outbreaks caused by Vibrio.

• Fisheries and Aquatic Sciences
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• 제16권3호
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• pp.137-142
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• 2013

To understand critical aspects of paralytic shellfish poisoning (PSP) in a chief area of bivalve production in Korea, seasonal variation in PSP toxins in bivalves collected from Jinhae Bay, Korea in 2009 was surveyed by the pre-column high-performance liquid chromatography oxidation method. We also confirmed the profiles of major bivalves such as oysters Crassostrea gigas and mussels Mytilus galloprovincialis in Jinhae Bay. PSP toxins in the bivalves showed remarkable seasonal variation. PSP toxin levels were detected from April to May in 2009, and the highest total toxin levels at all stations were recorded in May. The major toxins in bivalves were gonyautoxin [GTX] 1&4 and C 1&2; in oysters GTX 2&3 were also detected as major components. GTX 1&4, which showed the highest PSP toxin levels at each station, accounted for the highest proportions of toxin components in mussels and oysters (64.5-71.3% and 41.4-42.4%, respectively). It was also confirmed that the highest toxicity (in ${\mu}g$ saxitoxin [STX] eq/g) was derived from GTX 1&4. The highest total toxicity (in ${\mu}g$ STX eq/g) was approximately 2-8-fold higher in mussels than in oysters collected from the same station. PSP toxin levels in bivalves differed significantly according to the sample collection station. However, the profiles of toxins in the bivalves did not show significant differences during the survey period according to sample collection station. This study shows that PSP toxin levels in some samples from Jinhae Bay were above the regulatory limit in Korea during a specific period in spring.

• 한국수산과학회지
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• 제2권2호
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• pp.139-146
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• 1969

Incidents of poisoning caused by edible marine bivalve, Tapes philippinarum in Kojedo, Korea were reported in March 1968 and 1969. The results of the present investigation revealed that the incidents were caused by hemorrhagic diathesis and liver injuries, as those caused by acute yellow atrophic liver. The minimal lethal dose of the liver extract of the bivalve varied with seasons. The dose was 0.02ml in March and increased to 0.25ml in April-May 1969. After lune the extract showed no toxicity. Phthalein reaction of smashed liver solution of the bivalve showed a great variation with seasons. In March the values of $P_1$(crude solution) and $P_2$ (boiled one) were 0.1 and 10, at its strongest toxicity. In May those of $P_1\;and\;P_2$ were 1 and 1,000. However the mouse died after intraperitoneal administration of 0.25ml of the liver extract at the $P_2$ value of 1,000. For this reason, determination of the toxicity is difficult by judging from the phthalein reaction alone. The bivalves collected from Pusan, Kaduk, Koje, Hansan, Yeosu, Mokpo and Kunsan were found nontoxic during April-August 1969.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2003년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.373-374
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• 2003

There were many studies on the effects of red tide dinoflagellates on shellfish populations (Nielsen and Stromgren, 1991; Lesser and Shumway, 1993; Luckenbach et al., 1993; Matsuyama et al., 1997; Li et al., 2001). However, these studies mainly focused on the toxic effects of dinoflagellates oui adults or juveniles. Interactions between dinoflagellates and bivalve larvae have not been understood comprehensively yet. (omitted)

• Fisheries and Aquatic Sciences
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• 제9권4호
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• pp.153-159
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• 2006

The ark shell (or 'blood clam') Scapharca broughtonii is a filter-feeding bivalve that has red blood and inhabits waters approximately 10m in depth off the southern coast of South Korea. This study was part of a larger research project investigating the causes of death and restoration of shellfish resources, which are important aquaculture products in South Korea. We examined physiological responses related to survival, respiration, excretion, and amino acid changes as a result of changes in salinity. The 9-day median lethal salinity ($LS_{50}$) was 16.5 psu with confidence limits of 14.9-18.1 psu. At $25^{\circ}C$, the oxygen consumption and ammonia-nitrogen excretion rates were increased with decreases in salinity. Although the osmolality of individuals was acclimated within 2 h at 26.4 psu and 12 h at 19.8 psu, it took more than 5 days at a salinity of 13.2 psu, whereas no individuals acclimated and all died at a salinity of 6.6 psu. Of the amino acids present in the blood, taurine and alanine increased in response to decreased salinity. Tissues of the gill and the mid-gut gland were affected by decreasing salinity. These data will provide important fundamental information for examining the causes of mass mortality of shellfish in the summer.

• 한국패류학회지
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• 제31권4호
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• pp.279-283
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• 2015

본 연구는 해산 이매패 8종에 대해 패각 결정 (結晶)에 대한 분광학적 특성을 XRD 기법을 이용하여 조사하고 종간 근연관계에 대해 기존의 조사와 비교하였다. XRD분석을 수행한 결과, 바지락, 백합, 꼬막, 새조개의 패각은 $CaCO_3$의 orthorhombic 결정형인 aragonite였으며, 가리비와 굴의 패각은 trigonal-rhombohedral 결정형인 calcite였다. 담치와 키조개의 경우 aragonite와 calcite가 혼합된 결정으로 분석되었다. XRD를 이용하여 측정된 패각의 x-선 회절정보는 패류별 특이성을 나타내었으며, 이러한 특성을 이용한 과 (Family) 간 근연관계를 조사한 결과 현재 알려진 분류체계를 잘 대변하고 있었다. 결론적으로 패각 결정 (結晶)에 대한 분광학적 특성은 조사된 패류의 과 (Family) 수준에서 특이성을 잘 나타내며, 향후 종수준의 연구를 통한 종 동정을 위한 추가 연구가 필요함을 시사하였다. 또한 이러한 기술은 소량의 패각을 이용하므로 미확인 소량 절편의 패류 종 파악에 유용하게 이용될 수 있을 것으로 기대된다.

• 한국수산과학회지
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• 제50권4호
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• pp.335-342
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• 2017

Oysters Crassostrea gigas are a globally popular shellfish for human consumption. As filter-feeding bivalve mollusks, oysters may harbor many microorganisms and chemicals that could pose potential human health risks. The objective of this study was to investigate the suitability of cultured oysters for raw consumption or use in seafood products by measuring concentrations of harmful microorganisms and chemicals in their flesh. Microbial concentrations in cultured oysters were found to be: $1.0{\times}10^2-6.0{\times}10^4CFU/g$ (viable cell counts), not detected $(ND)-5.4{\times}10^3CFU/g$ (coliform bacteria), $ND-1.3{\times}10^2CFU/g$ (E. coli), and $ND-4.6{\times}10^3CFU/g$ (Vibrio parahaemolyticus). Other pathogenic bacteria, including Enterohemorrhagic E. coli (EHEC), Listeria monocytogenes, Staphylococcus aureus, and Salmonella spp., were not detected in any samples. Heavy metal concentrations of cultured oysters were ND-0.239 mg/kg (total mercury), ND-1.091 mg/kg (lead), ND-0.968 mg/kg (cadmium). The concentrations of benzo(a)pyrene ranged from $0.280-0.880{\mu}g/kg$. Paralytic shellfish poison ranged from ND-0.58 mg/kg, while diarrhetic shellfish poison was not detected. No radioactivity was detected. These results suggest that oysters intended for raw consumption or use in seafood products should be subjected to chemical and biological controls.