• 대한토목학회논문집
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• 제12권3호
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• pp.239-251
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• 1992

골프장에서 사용하는 농약에의한 오염 정도에 대해 많은 논쟁이 되고 있다. 이의 연구를 위해 기존의 골프장과 관련된 저수지와 하류수계에 대해 6개월 간에 걸쳐 조사하였다. 그중엔 부영양화에 관련된 수질항목들, 중금속, 농약, 그리고 수중 생태계 등의 전반적인 수질의 결과를 조사수계에 속한 골프장과 관련지어 분석하였다. 골프장으로부터 유출된 농약등의 오염이 조사수계의 수중 생태계에 미치는 영향은 심각한 정도가 아닌 것으로 나타났다. 골프장으로부터 유출되는 잔류농약의 분해를 돕기 위한 댐내에서는 수중 생태계가 잘 보전 돼있었고 전형적인 먹이의 연쇄가 확립돼 있었다. 일반적인 인식과는 달리 가축 축사와 논으로부터 유출되는 오염이 수계에 훨씬 더 약 영향을 미치는 것으로 나타났다.

• 한국동물생명공학회지
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• 제36권1호
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• pp.2-8
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• 2021

Dimethachlor is a synthetic herbicide, belonging to the chloroacetanilide group, that inhibits the undesirable growth of weeds via the suppression of very long-chain fatty acid synthesis. Although dimethachlor has been shown to run off from agricultural fields into aquatic ecosystems, the toxicity of dimethachlor on aquatic invertebrates and vertebrates is unknown. In our study, we assessed the toxicity of dimethachlor on developing zebrafish embryos by analyzing viability, hatching ability, and phenotypic changes. Embryonic viability decreased from 48 h post-fertilization (hpf) at the highest concentration of dimethachlor. Decreased hatching ratio, shortened body length, and pathological changes in the eye, heart, and yolk sac were observed at sub-lethal concentrations. Additionally, dimethachlor increased the number of apoptotic cells and level of reactive oxygen species 120 hpf. Our results indicate that dimethachlor may act as an anti-developmental toxicant when accumulated in an aquatic environment.

• 센서학회지
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• 제33권4호
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• pp.203-208
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• 2024

Every year, approximately 350 million tons of plastic waste are generated worldwide. This waste, can degrade into microplastics, owing to factors such as temperature changes and UV exposure. These smaller plastic particles are increasingly entering the food chain through marine life, thereby raising concerns about their impact on human health. Consequently, there is an increasing need to measure microplastics. Common methods involve direct collection by using a manta trawl equipped with a 330 ㎛ mesh net or performing spectroscopic and thermal analyses on collected samples. However, these methods require complex pre-processing, which risk sample destruction. In this study, we developed a system to directly sample microplastics in aquatic environments by using laser-induced fluorescence spectroscopy. Through an analysis of the fluorescence spectra as well as, the with gradient and integration at specific points, we successfully distinguished microplastics of 100, 200, 300, and 500 ㎛ in size, and we also differentiated between polyethylene (PE) and polystyrene (PS) types.

• 한국수산과학회지
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• 제56권3호
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• pp.309-314
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• 2023

Shark populations are constantly decreasing owing to environmental destruction and overfishing; thus, sharks are now at risk of extinction, with 30.5% of species classified as endangered on the International Union for Conservation of Nature's Red List. Sharks are apex predators and keystone species in balancing the marine food chain; their extinction would create an imbalance in the entire marine ecosystem. Assisted reproductive technology is a last resort for protecting animals facing extinction. Here, as a proactive effort toward building a hormone-induced artificial insemination protocol for endangered wild sharks, we identified the possibility of germ cell maturation by administration of GnRH, a commercially produced synthetic salmon gonadotropin-releasing hormone, and calculated its optimum dosage and injection timing. The experiment was conducted on one shark species, Chiloscyllium plagiosum. Injections were administered in 24 h intervals to C. plagiosum females, and 0.2 mL/kg+0.2 mL/kg were the optimal doses. These doses effectively induced maturation and, and ovulation, and oocyte release. Our results confirm that GnRH is a suitable tool for shark hormone-induced artificial insemination and indicate that this method may facilitate the conservation of endangered shark species.

• 한국수산과학회지
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• 제30권1호
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• pp.55-61
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• 1997

수산가공 부산물인 껍질을 효율적으로 이용하기 위하여 식용 젤라틴의 원료로 빨강오징어 껍질, 각시가자미 껍질, 홍대구 껍질, 대구 껍질 및 명태 껍질 등과 같은 껍질을 검색하였다. 콜라겐함량은 홍대구껍질이 $28.4\%$로 가장 높았고, 빨강오징어 껍질이 $11.1\%$로 가장 낮았으며, 기타 어류껍질의 경우 $23.5\~24.5\%$로 거의 차이가 없었다. 가용성 콜라겐조성은 어류껍질의 경우 $68.9\~84.8\%$, 빨강오징어 껍질의 경우 $44.3\%$이었다. 수산물껍질로부터 추출한 콜라겐의 아미노산조성은 가용성 및 불용성 획분간의 차이는 없었다. 수산물껍질 콜라겐은 모두 단량체인 $\alpha\;chain$과 이량체인 $\beta\;chain$으로 구성되어 있었고, 화살 오징어 껍질 콜라겐 및 홍대구 껍질 콜라겐을 제외한 나머지 3종의 껍질 콜라겐의 단량체는 hetero분자로 구성되어 있었다. 열변성 온도는 각시가자미 껌질 콜라겐이 기타 수산물 껍질 콜라겐보다 높았고, 또한 이들 수산물 껍질로부터 추출한 젤라틴의 물리적 특성도 콜라겐의 열 변성온도의 경향과 유사하였다.

• 한국수산과학회지
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• 제47권5호
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• pp.501-507
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• 2014

Norovirus (NoV) is a major cause of food poisoning outbreaks in Korea. Most NoV outbreaks originate from environmental contamination, but bivalves such as oysters are also important vectors. Oyster Crassostrea gigas contamination by NoV has been reported in Korea, but no quantitative analyses of NoV have been performed. We investigated the NoV concentration in 21 oyster samples from a Korean commercial oyster-growing area with confirmed fecal contamination from January to December 2012, using real-time reverse transcription-polymerase chain reaction. Additionally, we assessed the NoV concentration after heating to investigate the effects of heat treatment on NoV-infected oysters. In NoV-positive samples, the cycle threshold (Ct) values were 37.43-39.41 and 36.77-39.30, while viral concentrations were $8.97{\times}10^2-2.24{\times}10^2$ and $3.05{\times}10^2-7.47{\times}10^1$ copies/g for genogroups I and II, respectively. After heat treatment, NoV genogroup I decreased by 83.4%, 88.0%, 89.4% and 100% at $60^{\circ}C$, $68^{\circ}C$, $70^{\circ}C$, and $100^{\circ}C$, respectively, for 15 min, while genogroup II respectively decreased by 67.3%, 76.3%, 80.1%, and 89.8% under the same conditions.

• 한국수산과학회지
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• 제49권2호
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• pp.109-115
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• 2016

The efficacy of depuration following growing area translocation for the defecation of norovirus was evaluated under experimental conditions using oysters Crassostrea gigas previously subjected to bioaccumulation of this virus at a waste treatment plant discharge site. Three trials were assayed in an open experimental system with a commercial oyster farm located in a shellfish growing area approved by the Korean Shellfish Sanitation Program. Real-time reverse-transcription polymerase chain reaction (RT-PCR) was used to quantify viruses in the digestive glands of oysters. The final viral loads in oysters after 12 days remained under the detection limit (10 copies/g digestive gland) of the real-time RT-PCR. This reduction trend showed two-phase removal kinetics, with an initial slow reduction or slight increase in viruses during the first 2 days of depuration and subsequent stabilization with 0.12 to 2.64 log unit norovirus copies/g digestive gland per 2 days of depuration for the remaining time.

• 한국수산과학회지
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• 제34권6호
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• pp.672-677
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• 2001

2000년 5월 부산에서 수입 냉동어 S. stellatus에 의하여 발생한 설사성 식중독의 원인성분을 규명하기 위하여 조사한 결과는 다음과 같다. 식중독 환자들의 증상은 $0.5\~2$시간 (평균 1시간)에 증상이 시작되었으며 주된 증상은 소화기계의 설사 ($92\%$), 메스꺼움 ($77\%$), 복통 ($54\%$), 구토 ($46\%$), 두통 ($31\%$), 어지러움 ($23\%$), 발열 ($16\%$) 등의 순으로 나타났다. 어육 추출물로부터는 식중독과 관련된 어떠한 자연독 성분도 검출되지 않았으며, diacyl glycol빌 ethers (DAGEs)를 다량 함유한 특이 지질이 다량 ($23\%$) 함유되어 있었다. 설사의 원인으로 추정되는 DAGE의 alkyl chain에는 16:0, 18:1이 주성분이었으며 8개의 다른 장쇄 alkyl chain이 소량 함유되어 있었고, DAGEs의 sn-1,2에 결합된 주요 지방산은 oleic acid (18:1)이었다. DAGEs를 구성하는 분자종은 O-16:0-18:1-18:1($16.2\%$),O-16:0-18:1-22:1 ($14.7\%$), O-18:0-18:1-22:1 ($11.0\%$)이 주된 구성성분이었다.

• 한국수산과학회지
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• 제47권4호
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• pp.370-375
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• 2014

BACE2 is a membrane-bound aspartic protease that is highly homologous with BACE1. While BACE1 processes the amyloid precursor protein (APP) at a key step in generating ${\beta}$-amyloid peptide and presumably causes Alzheimer's disease (AD), BACE2 has not been demonstrated to be involved in APP processing directly, and its physiological functions are unknown. To determine its function and to develop inhibitors from marine sources, we constructed an overexpression vector for producing BACE2. The gene encoding human BACE2 protease was amplified using the polymerase chain reaction and cloned into the pET11a expression vector, resulting in pET11a/BACE2. Recombinant BACE2 protease was overexpressed successfully in E. coli as inclusion bodies, refolded using the rapid-dilution method, and purified via two-step fast protein liquid chromatography using Sephacryl S-300 gel filtration and Resource-Q column chromatography. The BACE2 protease produced was an active form. This study provides an efficient method not only for studying the basic properties of BACE2, but also for developing inhibitors from natural marine sources.

• 한국수산과학회지
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• 제47권3호
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• pp.220-226
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• 2014

Sixty-seven Vibrio parahaemolyticus isolates from surface seawater from the Wando area, on the southern coast of Korea, were analyzed for their susceptibility to 15 different antimicrobials and the presence of virulence genes. According to the disk diffusion susceptibility test, all of the strains studied were resistant to ampicillin and oxacillin, while decreasing percentages were resistant to vancomycin (64.2%), streptomycin (56.7%), amikacin (31.3%), kanamycin (22.3%), cephalothin (20.9%), erythromycin (10.4%), ciprofloxacin (4.5%), and tetracycline (3.0%). All of the strains were susceptible to five antimicrobials: chloramphenicol, gentamycin, nalidixic acid, sulfamethoxazole/trimethoprim, and trimethoprim. Fifty-nine isolates (88.1%) were resistant to three or more classes of antimicrobial and defined as multidrug resistant, and two strains were resistant to seven antimicrobial agents. The minimum inhibitory concentration (MIC) of the 67 V. parahaemolyticus isolates to ampicillin and oxacillin ranged from 512-2,048 and $64-512{\mu}g/mL$, respectively. All 67 isolates were also examined for the presence of the tdh and trh virulence genes using the polymerase chain reaction (PCR). However, no isolates possessed either tdh or trh. The VPA0477 (${\beta}$-lactamase) gene, present in all of the tested strains, was validated as a new specific marker gene in PCR assays for the accurate detection and identification of V. parahaemolyticus.