• Fisheries and Aquatic Sciences
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• 제15권2호
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• pp.151-155
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• 2012

We used nine microsatellite DNA markers to estimate genetic variation among wild and cultured populations of the sea squirt Halocynthia roretzi. The loci were polymorphic, with 6-32 alleles, and allelic richness ranged from 6.0 to 26.1 in each population. The wild and the cultured populations had similar mean heterozygosities ($H_O$ and $H_E$), allele numbers, and allelic richness. One cultured population with softness syndrome had a lower mean in the observed heterozygosity ($H_O$ = 0.57) and higher mean inbreeding coefficient ($F_{IS}$ = 0.261) than any other populations. This suggests that the loss of genetic variation in the diseased population might be due to increased inbreeding. A neighbor-joining tree and pairwise population estimates of $F_{ST}$ showed moderate genetic differentiation between the wild and the cultured populations. Additionally, the softness syndrome population was genetically divergent from wild populations, but it was genetically close to the cultured populations.

• 한국수산과학회지
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• 제46권1호
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• pp.18-26
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• 2013

This study examined the taste, nutritional and functional characterizations of commercial seasoned sea squirt Halocynthia roretzi (CSS). Total taste values of CSS ranged from 7.6 to 69.5 and the major free amino acids were glutamic acid and aspartic acid. Total contents of amino acids in CSS ranged from 5.91 to 7.59 g/100 g and the major amino acids were also glutamic acid and aspartic acid. When taking 100 g of CSS, the minerals that could be expected to have functional health effects (minerals whose levels were above 10% of the recommended daily requirements) were P, Mg and Fe. Other minerals were also present in non-negligible quantities. In terms of the functional properties of CSS, ACE inhibitory activity was 21.2-37.1%, antioxidative activity was 55.4-90.4%, xanthine oxidase inhibitory activity was 52.9-76.6% and ${\alpha}$-glucosidase inhibitory activity was 0-32%. Antimicrobial activity against Vibrio parahaemolyticus was not detected, but activity against Staphylococcus aureus, groups such as KB, GG, CY, DN, HC and KH, and against Escherichia coli groups such as SF, WD, KB and GG, was detected.

• 한국수산과학회지
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• 제46권1호
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• pp.10-17
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• 2013

This study investigated the food biochemical characterization of commercial seasoned sea squirt Halocynthia roretzi (CSS). The proximate composition of CSS was 77.2-82.7% moisture, 7.1-9.1% crude protein, 0.3-2.6% crude lipid and 3.5-6.3% ash. Taste compound contents of CSS were 2.3-5.4% salinity (saltiness), 0.42-1.12 g/100 g total acidity (sourness) and 114.9-330.2 mg/100 g amino nitrogen (taste intensity). The Hunter color values of CSS were 23.79-32.50 for lightness, 9.97-20.45 for redness, 14.01-20.96 for yellowness and 64.50-76.63 for color difference. The odor intensity of CSS was 35.0-62.0. According to these results, there were large differences in proximate composition, taste compounds, Hunter color values and odor intensity of CSS. Viable cell counts ranged from 6.20 to 7.69 log (CFU/g), and most of the viable cells comprised of lactic acid-forming bacteria. CSS was not detected in the coliform group.

• 한국수산과학회지
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• 제53권2호
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• pp.244-250
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• 2020

Microplastic pollution in the marine ecosystem has been emerged as a global issue. In this study, we investigated the abundance of microplastics from clam Meretrix lusoria, blood arkshell Scapharca broughtonii, and warty sea squirt Styela clava obtained from a local market in Busan, Korea. The marine organisms were digested in 10% KOH, and were incubated at 40℃ and 150 rpm, for 7 days. The digest was filtered through standard sieve (5 mm, 1 mm, 300 ㎛, and 100 ㎛), and mciroplastics were identified using a light microscope and microFT-IR. The abundance of microplastics of clam, blood arkshell, warty sea squirt was 0.08 items/g, 0.05 items/g, and 0.12 items/g, respectively. The predominant microplastic size was in the range of 100-300 ㎛, occupying 48%, and the predominant type was fiber. The composition of microplastics was mostly rayon, semi-synthetic cellulosic material and polyester, which are main component of fabric and textile. We strongly believe that this preliminary work may provide useful information for the establishment of the standardized analysis method of microplastics ingested by marine organisms.

• 환경생물
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• 제30권4호
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• pp.349-354
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• 2012

To evaluate the biological response of sea squirt Halocynthia roretzi with different body size to heavy metals and its suitability for ecotoxicity assays, the effects of Cr, Cu and Zn on its clearance and oxygen consumption rates were investigated. Clearance and oxygen consumption rates of H. roretzi with various body sizes were calculated at different metal concentrations. Both clearance and oxygen consumption rate were negatively correlated with body sizes. Clearance rate of H. roretzi decreased gradually with increasing concentration of heavy metal, the decreasing rate was in an order of Cr>Cu>Zn. The oxygen consumption rate first increased at low metal concentration (below $100{\mu}g\;L^{-1}$) and then decreased rapidly with increasing metal concentrations. The decreasing rate was in an order of Cu>Cr=Zn. There was a trend that the clearance rate and oxygen consumption rate decreased drastically under a concentration of $400{\mu}g\;L^{-1}$, and then decreased smoothly when the metal ion concentration increased continually. So the oxygen consumption and clearance rate at a concentration of $400{\mu}g\;L^{-1}$ Cu could be thought as a suitable biological tool for exotoxicology analysis.

• 한국발생생물학회지:발생과생식
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• 제5권2호
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• pp.137-144
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• 2001

본 연구는 동해남부해역의 수하식 우렁쉥이 양식장에서 양식되고 있는 2년산 우렁쉥이, Halocynrhia roretzi의 생식세포 및 생식소 발달과 성숙 조사를 위하여 1996년 5월부터 1997년 4월에 걸쳐 조사되었다. 우렁쉥이는 자웅동체형으로 난생이었다. 난소는 체벽에 평행하게 붙어 좌측에 6~8개, 우측에 8~10개의 가는 생식수관을 가진 구조이며, 정소는 난소 사이에 불규칙 한 많은 낭상 구조를 가진 복합 생식소이었다. 난원세포는 직경이 11.7~15.6 ${\mu}m$이었고, 초기성장기의 난모세포는 직경 39.6~47.6 ${\mu}m$이었으며, 핵경은 10.0~25.0 ${\mu}m$이었다. 난소를 대부분 차지하는 난황형성중인 난모세포는 158.6~210.0 ${\mu}m$에 이르렀다. 성숙 난모세포는 210.0~230.9 ${\mu}m$로 피질부에서 test cell들이 관찰되었다. 정소는 한 개의 정소낭에 여러 개의 곡정세관이 밀집되어 그 내부 생식상피를 따라 일반적인 정자형성과정을 보이고 있었다. 첫 산란은 수온이 1$0^{\circ}C$이하로 떨어진, 3년생이 되는 1997년 1월에서 2월에 주로 이루어졌다.

• 한국환경보건학회지
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• 제6권1호
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• pp.43-46
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• 1979

Author studied on the distribution of Vibrio parahaemolyticus the sea water and shellfish, oyster, sea squirt in the protof Busan in 1978. The results obtained were as follows: The numbers of Vibrio parahaemolyticus isolated from the sample of sea water and marine products 80 cases were 11 strains (13.8%).

• 수산경영론집
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• 제8권2호
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• pp.21-40
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• 1977

• 해양환경안전학회지
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• 제13권4호
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• pp.15-19
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• 2007

2006년 8월 경북 연안의 우렁쉥이 앙식장에서 대량폐사가 발생하였다. 폐사 원인을 규명하기 위하여 폐사 직후 폐사가 발생한 양식장을 대상으로 수질환경 조사와 병리학적 조사를 실시하였으나 특이점을 발견하지 못하였다. 그래서 폐사가 발생하기 직전 동해에 영향을 미친 10호 태풍 '우쿵'이 우렁쉥이 폐사에 영항을 미쳤을 것으로 가정하고 태풍 '우쿵' 통과 전후의 해황 자료를 분석하였다. 태풍 우쿵의 영향을 받기 전인 8월 초 중순 동해 연안은 전반적으로 저층 냉수의 용승으로 인하여 수심 10m 이심에서는 $15^{\circ}C$ 이하의 찬물이 존재하고 있었다. 그 후 매풍 '우쿵'의 영향으로 인한 북풍이 약 5일간 지속되면서 수온이 높은 외측의 표층수가 연안으로 밀려와 침강하는 현상(에크만 효과)이 발생하여 우렁쉥이가 매달려 있는 수심 $10{\sim}20m$의 수은이 일시에 $10^{\circ}C$ 이상 상승하여 약 5일간 지속되었다. 2006년 경북 연안의 양식 우렁쉥이는 장기간 냉수에 적응되어 있다가 태풍 '우쿵'의 영향으로 수온이 급상승함에 따른 수온 스트레스로 인하여 대량폐사된 것으로 추정된다.

• 한국식품영양과학회지
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• 제24권2호
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• pp.274-279
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• 1995

미더덕의 계절에 따른 성분 조성을 분석하여 식품학적 기초자료를 얻고자 3~10월 사이의 정미성분과 그 계절적 변화를 실험한 결과를 요약하면 다음과 같다. 미더덕의 총엑스분질소량은 6월에 294mg/100g, 7월에 160mg/100g으로 감소하다가 그 이후 증가하는 경향을 보였으며, 유리아미노산 중 taurine(45~50%)과 proline(12~18%)이 가장 많았으며, 그밖에 glutamic acid, alanine, glycine의 함량이 많았다. 핵산관련물질 중에서는 AMP의 함량이 가장 풍부하였고, glycine betain은 6월에 256mg/100g으로 최고치를 보였다. 미더덕의 엑스 분질소 조성은 유리아미노산이 50~62%로 가장 높았으며, 다음으로 betaine(11~15%), 핵산관련 물질(5~8%), TMAO 및 총 ceratinine 순이었다. 미더덕의 유기산은 succine, malic, lactic 및 pyroglutamic acid가 전체 유기산의 80% 이상을 차지하였으며, 그 중 succinic acid의 함량이 가장 높았다. Omission test한 결과, 미더덕의 맛은 유리아미노산, betaine, 핵산관련 물질, 불휘발성 유기산 순으로 영향을 미치는 것으로 나타났다.