• 한국수산과학회지
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• 제36권3호
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• pp.210-219
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• 2003

To develop natural flavoring substances, optimal two stage enzyme hydrolysis conditions and flavor compounds of short-neck clam (Tapes philippinarum) enzyme hydrolysates were examined. The optimal enzyme hydrolysis conditions for two stage enzyme hydrolysate (TSEH) of short-neck clam were revealed in temperature at $55^{\circ}C$ for 4 hours digestion with alcalase at the 1st stage and 4 hours digestion at $45^{\circ}C$ with exopeptidase type neutrase at the 2nd stage. In quality tests of hot-water extracts, steam extracts and 4 kinds of enzyme hydrolysates, TSEH processing method was superior to other methods in yield, nitrogen contents, organoleptic taste such as umami intensity and inhibition of off-flavor formation, and transparency of extract. Total free amino acid contents in hot-water extract, steam extract and TSEH were 1,352.1 mg/100 g, 1,174.1 mg/100 g and 2,122.4 mg/100 g, respectively, Major free amino acids in TSEH were glutamic acid, glycine, alanine, tyrosine, phenylalanine and arginine. As for nucleotides and other bases, betaine, TMAO and creatinine were principal components in TSEH. The major inorganic ions in TSEH were Na, K, P and Cl. TSEH also revealed very higher angiotensin-I converting enzyme inhibition effect $(70.7\%)$ than those of hot-water and steam extract. We conclude that TSEH from short-neck clam was more flavorable compared with the seasoning materials on the market, it could be utilized as the instant soup base and the seasoning substances for fisheries processing.

• 한국수산과학회지
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• 제30권1호
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• pp.114-118
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• 1997

국내 유통중인 패류의 토사처리기술개발을 위한 기초 연구의 일환으로 바지락을 중심으로 수온, 염분 및 염화 마그네슘의 농도에 따른 바지락의 토사특성을 검토하였다. 패류의 기본 수계인 해수를 이용하여 토사처리효과를 분석한 바, 꼬막, 피조개 및 동죽은 충분히 토사가 가능한 것으로 나타났으나 바지락은 해수처 리만으로는 불완전한 것으로 평가되었다. 바지락의 토사는 처리수로서 담수를 이용할 경우 이들의 서식환경과 유사한 $2.5\%\;NaCl(pH\;8.0),\;25^{\circ}C$ 조건에서 극대를 나타냈으며 이 조건에 $50\;mM\;MgCl_2$를 첨가시 1.57배의 토사촉진효과를 보였다. 이상의 조건과 해수 및 해수$+20mM\;MgCl_2$ 조건에서 48시간 처리후 토사 배출량을 비교했을 때 해수 $+20mM\;MgCl_2$, 해수, $2.5\%\;NaCl$ (담수)$+50mM\;MgCl_2,\;2.5\%\;NaCl$의 순으로 높게 나타나고 있었으며 이 결과는 관능검사에서도 유효한 것으로 확인되었다. 따라서 바지락의 서식환경과 Mg이온은 바지락의 생물활동과 토사에 깊은 관련이 있는 것으로 추론되었다.

• 한국수산과학회지
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• 제47권5호
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• pp.508-515
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• 2014

The contamination status of Vibrio parahaemolyticus in commercially valuable shellfish from the south and west coasts of Korea and the antimicrobial resistance patterns of isolated V. parahaemolyticus were investigated from July through October, 2011. The range of V. parahaemolyticus concentrations in oysters Crassostrea gigas and short neck clams Venerupis philippinarum was <30~290 MPN/100 g and <30~46,000 MPN/100 g, respectively, and greater than 10,000 MPN/100 g of V. parahaemolyticus was detected from 7 of 40 short neck clams. During the survey period, 436 strains of V. parahaemolyticus were isolated (129 from oysters and 307 from short-neck clams) and the antimicrobial resistance patterns of all of the isolates were examined. Antimicrobial resistance against at least one antibiotic was seen in 79.8% of the oyster isolates (103 strains) and 63.8% of the short neck clam isolates (196 strains). The antimicrobial resistance patterns were relatively simple because the antimicrobial resistance of the isolates was simply due to resistance to ampicillin. Only one oyster isolate and three short neck clam isolates showed multiple antibiotic resistance, i.e., resistance against more than four antibiotics.

• 한국수산과학회지
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• 제45권5호
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• pp.465-471
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• 2012

To compare the accumulation of paralytic shellfish poison (PSP) in different marine organisms, the occurrence and variation of PSP were surveyed in blue mussel Mytilus edulis, oyster Crassostrea gigas, short neck clam Ruditapes philippinarum, bay scallop Argopecten irradians, and warty sea squirt Styela clava collected from Jinhae Bay, Korea, in 2005 and 2006 year. We also investigated the ability of the blue mussel to detoxify PSP by relaying and depuration (via the water flow or water circulation system). In the marine organisms examined, PSP levels were the highest in blue mussel, followed in order by bay scallop, oyster, short neck clam, and warty sea squirt. Comparing the maximum PSP levels in the bivalve species examined in 2005 and 2006, PSP in blue mussel was 1.6-2.0, 4.0-5.9, and 5.1-6.0 times higher than in bay scallop, oyster, and short neck clam, respectively. Therefore, blue mussel could be useful as a bioindicator for PSP monitoring. With the increasing PSP levels in blue mussel in 2006, the proportion of PSP in its digestive gland increased to 95.1% when the maximum level was detected from the whole tissues of blue mussel on May 29. Subsequently, the PSP proportion in the digestive gland decreased as the PSP level in whole tissue decreased. The detoxification of PSP in blue mussel was greatest with relaying, followed by the water flow, and water circulation systems. Relaying decreased the PSP level below the regulatory limit of $80{\mu}g$/100 g after 2 days in low toxic sample with $124{\mu}g$/100 g, and after 7 days in high toxic sample with $401{\mu}g$/100 g. During depuration in the blue mussel with $401{\mu}g$/100 g via the water flow system, the PSP amounts in the digestive gland decreased by about 50% after 1 day, and about 77% after 7 days. In contrast, the PSP amounts in the soft body, gill, and mantle did not change significantly with depuration.

• 한국수산과학회지
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• 제54권6호
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• pp.896-903
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• 2021

For the safety assessment of microbiological and chemical hazards in raw short-neck clam Ruditapes philippinarum distributed in the Yeongnam and Honam areas during the spring season, the contamination levels of total viable bacteria, coliforms, Escherichia coli, and nine pathogenic bacteria (Staphylococcus aureus, Salmonella spp., Vibrio parahaemolyticus, Clostridium perfringens, Listeria monocytogenes, enterohemorrhagic Escherichia coli, Yersinia enterocolitica, Bacillus cereus, Campylobacter jejuni) as microbiological hazards, and heavy metals (lead, cadmium, total mercury), benzopyrene, shellfish poison (paralytic, diarrhetic, amnesic), and radioactivity (¹³¹I, ¹³⁴Cs+¹³⁷Cs) were also analyzed in 15 samples based on the methods of the Korean Food Code. The average contamination levels of total viable bacteria were 3.11 (1.40-4.49) log CFU/g, and coliforms were detected in 5 out of 15 samples (1.18-1.85 log CFU/g). E. coli and S. aureus were not detected in all samples. Furthermore, the presence of 8 pathogens were not detected in all samples. The average contamination levels of lead, cadmium, and total mercury were 0.155 (0.079-0.264), 0.160 (0.040-0.287), and 0.017 (0.008-0.026) mg/kg, respectively. Benzo(a)pyrene, shellfish poison, and radioactivity were not detected in all samples. The results of this study suggest that the safety against all microbiological and chemical hazard factors in raw short-neck clams distributed in markets has been assured.

• 한국수산과학회지
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• 제49권4호
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• pp.460-466
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• 2016

From 2013 through 2015, we investigated the contamination status and antimicrobial resistance patterns of pathogenic Vibrio parahaemolyticus in commercially valuable seawater and shellfish (Oyster Crassostrea gigas, short-neck clam Venerupis philippinarum, ark shell Scapharca broughtonii and mussel Mytilus galloprovinciallis) from the southern coast of Korea. The detection rate of V. parahaemolyticus was highest in short-neck clams (23.7%), followed by ark shells (19.2%), oysters (15.9%), mussels (13.6%), and seawater (8.6%). The following percentages of PCR assays of shellfish were positive for the thermostable direct hemolysin-related hemolysin gene (trh) : oysters (12.8%), short-neck clams(11.8%), and ark shells (3.4%). Similar assays for the thermostable direct hemolysin gene (tdh) resulted in positive results for short-neck clams (5.9%) and ark shells (3.4%). Antimicrobial resistance was present in 100% of 8 tdh (+) and 2 trh (+) V. parahaemolyticus isolates challenged with ampicillin. However, all pathogenic V. parahaemolyticus were sensitive to 14 other antibiotics. To ensure the safety of shellfish consumption, the continuous monitoring of the prevalence and distribution of virulence factors of V. parahaemolyticus in shellfish farms is needed.

• 동아시아식생활학회지
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• 제11권4호
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• pp.289-294
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• 2001

서해안에서 수집한 모시조개, 바지락. 맛조개. 꼬막, 소라 및 굴 등 6종의 조개류의 껍질수율과 외관, 껍질 및 열수 추출물의 무기질 및 중금속 함량을 조사하였다. 조개류 껍질의 비율은 70.1~80.5% 범위였으나 맛조개는 40.7%로 낮았다. 개체당의 껍질무게는 소라가 26.2 g으로 가장 높았고 맛조개가 5.6 g으로 가장 낮았다. 모시조개껍질은 노랑색을 띈 갈색, 바지락은 밝은 갈색. 맛조개와 꼬막은 검은색이었고 소라는 녹색을 띄는 갈색을, 굴은 어두운 회색을 띄었다. 조개류의 주 무기질은 Ca로 36.23~38.78%였으며, K는 0.23~4.54%, Na는 1.48~l.59%였다. 그외 Na, Mg, Fe, Mn, Zn, Cu, P, S 등은 0.0l~0.21% 범위로 함유되어 있었다. 중금속으로 Pb는 1.90~7.75 ppm, Cd는 0.5~4.50 ppm, As는 1.40~4.30 ppm, Se는 0.2~l.50 ppm Cr은 1.00~8.30 ppm, Hg는 0.002~8.2ppm이었다. 조개류 껍질로부터 물에 의하여 추출되는 Ca의 함량은 l15~2.448 mg/100g으로 맛조개가 가장 높았으며 바지락이 가장 낮았다. 물에 의하여 추출되는 K는 10~952 mg/100 g으로 모시조개가 가장 낮았고, 맛조개가 가장 높았다. 조개껍질의 무기질 추출율은 맛조개에서 전반적으로 높았으며 종류에 따라서 상당한 차이를 나타내었다. 특히. P는 맛조개가 201 mg/100 g으로 바지락 0.36 mg/100g에 비하여 현저히 높았다. Pb. As, Se 및 Cr의 물추출량은 맛조개에서 가장 높았으며 각각 110. 40, 90 및 20 $\mu$g/100 g이었다. 그러나 Cd는 바지락껍질에서만 검출되었다.

• 한국식품영양과학회지
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• 제32권2호
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• pp.161-166
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• 2003

천연의 칼슘자원인 조개류 껍질 물추출물을 사용하여 보존성이 높고 체내 흡수력이 양호한 젖산칼슘의 함량이 높은 김치의 제조를 시도하였다. 시료는 꼬막, 맛조개, 모시조개, 바지락, 굴 및 소라껍질의 물 추출물을 사용하였으며 절임배추에 대하여 5%를 첨가하여 1$0^{\circ}C$에서 숙성시켰다. 조개류 껍질의 칼슘함량은25.57~38.78%이었다. 조개류 껍질 물추출물을 첨가한 김치의 pH는 전 숙성 기간을 통하여 대조구보다 높았으며 산도는 특히 숙성 후기 에 낮았다. 총 균수는 조개 껍질 물추출물 첨가구가 대조구보다 낮았으나 젖산균수는 첨가구에서 높았다. 숙성 7일 이후의 조회분 함량은 첨가구 (3.31~4.99%)가 대조구(2.75~3.01%)넓다 높았다. 칼슘의 함량은 첨가구(300.2~376.0 mg%)가 대조구(69.9~95.0mg%) 보다 높았으며, 그 중에서도 굴 껍질과 모시조개 껍질 물추출물을 첨가한 김치에서 높았다. 조개류 껍질 물추출물을 첨가한 김치는 대조구에 비하여 아삭아삭한 조직감(crispiness)이 높은 반면 산미는 약했으며, 종합적 인기호도는 담금일 에는 차이를 보이지 않았으나 숙성 14일 이후에는 전반적으로 첨가구에서 높았다.

• 한국수산과학회지
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• 제42권1호
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• pp.8-14
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• 2009

To prevent the food poisoning originated by consumption of shellfish contaminated with domoic acid, the quantitative analysis of domoic acid is to be very important. The stability of domoic acid at different temperature, pH and light was investigated using high performance liquid chromatography (HPLC). The mean recoveries of domoic acid in the methanol extracts from oyster (Crassostrea gigas), blue mussel (Mytilus edulis), short neck clam (Ruditapes philippinarum) and ark shell (Scapharca broughtonii) were 85.4-104.5%, 94.8-101.2%, 91.0-104.6%, and 95.7-109.6%, respectively. The working solutions of domoic acid standard were very stable for one month at $-18^{\circ}C$, $4^{\circ}C$, and room temperature. And domoic acid in the methanol extract from oyster was stable for a day at $4^{\circ}C$ and room temperature, and for a week at $-18^{\circ}C$. Therefore, this implies that quantitative analysis for domoic acid must consider the storage conditions of the standard solutions and the methanol extracts from shellfish. The standard solutions adjusted to pH 3-9 were also stable after heating at $121^{\circ}C$ for 30 min. The effect of light exposure on domoic acid was tested by exposing the methanol extracts to light. Domoic acid degraded slowly when the samples were kept in the dark (brown vial). However, following the light exposure the photodegradation became more rapid; no detectable domoic acid remained in $1.0{\mu}g/mL$ of methanol extract after 5 hours.

• 한국수산과학회지
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• 제53권5호
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• pp.752-760
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• 2020

Acute hepatopancreatic necrosis disease (AHPND), previously known as early mortality syndrome (EMS), is an emerging disease in shrimp caused by Vibrio parahaemolyticus. Some V. parahaemolyticus strains are associated with foodborne diseases in humans. To date, studies on the relationship between AHPND and pathogenic V. parahaemolyticus are very limited. In this study, we monitored the thermostable direct hemolysin-related hemolysin (trh) gene and AHPND-related genes, such as Photorhabdus insect-related (pir) genes, in 892 strains of V. parahaemolyticus isolated and identified in 24 areas of the West Coast of Korea from May to October 2019. The trh gene was detected in 9.6% of the isolates from short neck clam samples. However, the pirA and pirB genes related to AHPND were not found in any of the isolates despite using both duplex and nested PCR assays, suggesting that AHPND-related genes were nonexistent in the V. parahaemolyticus strains isolated. This study contributes to the current understanding of the relationship between AHPND and V. parahaemolyticus in Korea, as well as provides data on spatial and seasonal distributions of V. parahaemolyticus.