• Fisheries and Aquatic Sciences
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• 제6권1호
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• pp.34-40
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• 2003

Three panel trammel nets were made illegal for the brown shrimp (Penaeus japonicus) or fishes by Korean fisheries law while trammel nets for fleshy prawn in the West sea remained legal. In this study a single panel tangle net with vertical loop lines rigged between the float line and sinker line was specially designed to catch brown shrimp. This net was developed for the first time after observation of the brown shrimp behaviour when reacting to a net in an observation tank. In field experiments these single tangle nets were compared with the traditional trammel nets in the coastal waters of the Keoje area. The mean number of the brown shrimp for 53 fishing operations was 1.13 per unit panel of the single tangle nets when fitted with the vertical loop lines. This was $84\%$ of the mean catch of 1.36 achieved with the trammel nets. These results of fishing experiments using single tangle nets in the field revealed a high fishing efficiency for the brown shrimp and showed little difference from trammel nets. The size of the brown shrimp or number of by-catch was not different between single tangle nets and trammel nets.

• Fisheries and Aquatic Sciences
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• 제1권2호
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• pp.201-208
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• 1998

A protease, which had no tryptic and chymotryptic activity, was purified from the hepatopancreas of shrimp, P. japonicus, through ammonium sulfate fractionation, Q­Sepharose ionic exchange, benzamidine Sepharose 6B affinity, and Sephacryl S-100 gel chromatography. Molecular weight (M.W.) of the protease was estimated to be 24 kDa by gel filtration and showed a single peptide band by sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). The protease had a low ratio of acidic to basic amino acids, which is different with pro teases from marine animals. The enzyme was partially inhibited by benzamidine, tosyl-L-lysine chioromethyl ketone (TLCK), phenylmethylsulfonyl fluoride (PMSF), soybean trypsin inhibitor (SBTI), and pepstatin. The enzyme did not have any activity against benzoyl-D,L-arginine p-nitroanilide (BAPNA) or benzoyl-L-tyrosine ethyl ester (BTEE) which is a specific substrate of trypsin and chymotrypsin, respectively. However, the enzyme showed activity forward N-CBZ-L-tyrosine p-nitrophenyl ester (CBZ-Tyr-pNE), N­CBZ-L-tryptophan p-nitrophenyl ester (CBZ-Trp-pNE), and N-CBZ-L-proline p-nitrophenyl ester (CBZ-Pro-pNE). The protease did not showed tryptic and chymotryptic activity, which was not reported in shrimp hepatopancreas.

• 한국수산과학회지
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• 제3권3호
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• pp.161-171
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• 1970

보리새우(Penaeus japonicus Bate)의 섭이량, 주간, 야간 섭이율과 일간 섭이율, 이료의 종류에 따른 섭이률의 차이, 보리새우의 성장과 이료의 전환효율등에 관해서 시험한 결과를 요약하면 다음과 같다. 1. 보리새우의 섭이율은 수온범위 $19\~30^{\circ}C$, 체중범위 $1.6\~14.9g$에서 수온이 높을수록, 또 새우의 크기가 작을수록 커지며, 평균 일간 섭이율은 $18\~44\%$에 달한다. 2. 항상 야간 섭이율이 주간 섭이율보다 크나, 무저질, 암상태 또는 직접광선을 피한 사육상태에서는 주간에도 일간 섭이률의 $22\~37\%$의 섭이를 이룩할 수가 있어, 그만큼 보리새우의 성장을 촉진시킬 수가 있었다. 3. 멸치와 바지락의 두가지 이료에서는 주야의 구별없이 멸치를 한층 더 많이 섭취하였으며, 일간 섭이율중에서 멸치 및 바지락육의 섭이율은 각각 $12.9\%$, $10.3\%$이었다. 4. 보리새우의 체중(W;g)과 일간 성장률 ($DGR;\%$) 사이에는 log DGR=0.7035-0.7864 logW의 관계식이 성립되고, 새우의 크기에 비예하여 일간 성장율은 작아진다. 5. 보리새우의 이료의 전환효율은 새우의 크기에 따라 큰 차이가 없이 평균 $2.8\~7.8\%$의 범위로 변동하며, 지금까지 알려진 어류 (문치가재미, 고등어, 방어 등)와 참오징어의 그것에 비교하면 매우 작은 값을 취한다.

• 한국수산과학회지
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• 제29권3호
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• pp.393-408
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• 1996

우렁쉥이 껍질 색소추출물을 astaxanthin 함량으로 환산하여 100ppm, 200ppm 및 400ppm 첨가 한 후 보리새우를 8주간 사육하여 성장도, 착색정도, 지질 및 총 콜레스테롤 함량 그리고 육과 머리의 지방산조성을 조사하였다. 성장율은 대조구(Diet 1)가 가장 낮아 0.610이었고, carophyll pink 첨가구(Diet 2)가 1.065, 껍질 색소추출물 첨가구인 Diet 3(100ppm), Diet 4(200ppm), Diets (400ppm)는 각각 1.227, 1.292, 1.264로 Diet 4 첨가구가 가장 양호하였다. 총카로테노이드 함량은 대조구가 8주 후 육 및 껍질 중 0.176mg, 1.429mg으로 감소하였으나, 색소추출물구인 Diet 4와 5는 각각 2.337mg, 6.331mg으로 가장 우수하였다. Astaxanthin monoester가 free형보다 착색에 더 영향을 미치는 것으로 나타났다. 육 및 머리 중 지질함량도 Diet 4, 5가 8주 후 각각 1632.7mg, 1691.4mg, 1973.5mg, 2071.1mg으로 가장좋았고, 육 및 머리의 콜레스테롤 축적량은 Diet 2가 8주 후 각각 481.5mg, 199.5mg이었으나, Diet 4는 각각 978.2mg, 563.8mg으로 성장에 직접 영향을 미치는 것으로 나타났다. 머리 지질 중 총지질(TL) 및 중성지질(NL)의 지방산조성은 모노엔산의 함량이 높고 고도불포화지방산(PUFA) 함량은 낮았으나, 이와는 반대로 국성지질(PL)은 모노엔산 함량은 낮고 PUFA 함량은 높아 인지질 중 n-3계 고도불포화지방산의 비율이 높게 나타나 색소추출물이 필수지방산 공급원의 역활을 하는 것으로 나타났다.

• 한국양식학회지
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• 제13권4호
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• pp.309-316
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• 2000

조간대에서 서식하는 비늘흰발망둑의 섭식 생태를 파악하여 연안 생물 군집의 먹이 사슬에 관한 기초 지식을 얻고자, 1996년 7월부터 1997년 6월까지 충남 서천군 서면 도둔리에서 매월 1회씩 비늘흰발망둑을 채집하여 위 내용물 분석을 통해 섭식 생태를 조사하였다. 위 만복도는 하루 중 오전과 오후에 각각 한 차례식 증가하는 경향을 보였다. 비늘흰발망둑(1.2~5.9cm SL)의 주요 먹이생물은 십각류(유영류 유생, 젓새우, 보리새우 및 보행류 유생), 단각류(카프렐라류, 옆새우류 및 하이페리아류), 요각류(Acartia sp., Calanus sinicus, Corycaeus affinis 및 Microsetella sp.) 등으로 식성이 육식성이었다. 그 외 등각류, 만각류 유생, 다모류 유생 및 구각류 등이 소량씩 위 내용물 중에서 발견되었다. 비늘흰발망둑이 성장함에 따라 먹이생물의 조성비가 점차 변하였다. 체장이 작은 비늘흰발망둑은 요각류, 십각류 및 단각류 순으로 먹었으나, 체장이 증가하면서 요각류의 비율은 점차 낮아진 반면, 십각류와 단각류가 위 내용물 중 차지하는 비율은 점차 증가하였다.

• 한국수산과학회지
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• 제4권1호
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• pp.1-6
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• 1971

In order to study the catching efficiency of shrimp trawl equipped with electrodes around the net mouth and stimulant devices attached to the ground rope, an experimental operation was carried out at Oma-Island Shrimp Farm from October 3rd to November 5th, 1970. Many studies have been made on the shrimp trawl with electric stimulant devices, but few can be found for detailed scientific catching methods. Electric power consumption was so excessive that electric stimulant devices could not be developed for commercial purposes. As a first step toward the successive operations of the electric stimulant devices in the field, it is necessary to study fundamental principles, such as electric current, voltage, electric potential, potential difference, electric field and suitable pulse. The behaviour response of the common shrimp, Penaeus japonicus BATE to moving nets and electric stimulant devices were reported in the preceding papers based on the water tank experiments (Ko and Kim, 1970). Through comparative fishing tests the rate of catching efficiency during daylight time was confirmed to be from 89 to 96 per cent of the night catch efficiency, and with 30 V. 1.5 A. electric power was sufficent for practical sea operation.

• 한국수산과학회지
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• 제29권6호
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• pp.797-804
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• 1996

Two trypsins were purified from shrimp hepatopancreas through ammonium sulfate fractionation, Q-Sepharose ionic exchange, benzamidine Sepharose-6B affinity, and Sephacryl S-300 gel chromatography. Both enzymes had a single polypeptide chain with a molecular weight (M.W.) of 32 kDa by sodium dodecylsulfate polyacrylamide gel electrophoresis (SOS-PAGE), although trypsin A and B were estimated to be a molecular weight of 27.2 and 22.8 kDa, respectively, using Sephacryl S-300 gel filtration. Both trypsins had similar amino acid compositions and rich in glycine, valine, alanine, aspartic acid, and glutamic acid, but low in methionine and basic amino acids. Both enzymes were completely inactivated by soybean trypsin inhibitor (SBTI), phenylmethylsulfonyl fluoride (PMSF), tosyl-L-lysine chloromethyl ketone (TLCK), benzamidine, leupeptin, however, not affected by tosyl-L-phenylalanine chloromethyl ketone (TPCK) and pepstatin.

• 한국양식학회지
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• 제15권1호
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• pp.7-13
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• 2002

Since 1993, the White Spot Syndrome Virus (WSSV) disease occurred in China among cultured shrimps resulting in mass mortality. Epizootiological surveys undertaken during the outbreak period of 1993-1994 indicated that all stages of Penaeus chinensis, P. japonicus and P. monodon were infected. Consequent to the transport of contaminated shrimp seedlings and seawater, the disease spread all over the farms of China. The disease was more rapidly transmitted at temperatures above $25^{\circ}C$. Challenge experiments showed the causative agent was highly virulent. White spots appeared on the carapace of both span-taneous and experimentally infected shrimps. Moribund shrimps contained turbid hemolymph, hypertrophied Iymphoid organ and a necrotic mid-gut gland. Electron microscopy showed the presence of viral particles in the gills, stomach, lymphoid organ, and epidermal tissue of the infected shrimp. The visions were slightly ovoid with an envelope and averaged 350 $\times$ 150 nm; nucleocapsids measured 375 $\times$ 157 nm. With discontinuous sucrose gradient of 35, 50 and 60% (w/v), the virus was separated from hemolymph of the infected shrimp. The estimated molecular weight of genomic DNA was 237 Kb with EcoR I, 247 Kb with Hind III and 241kb with Pst I. A total of 9 hybridoma colones secreting monoclonal antibodies (MAbs) were produced from mouse myeloma and spleen cells immunized with WSSV. The immunofluorescence assay of gill tissue showed that the MAbs reacted with diseased but not with healthy shrimp. The MAbs belonged to IgGl, IgG2b subclass and IgM class, all with kappa light Immune-electron-microscopy with colloidal gold marker showed the presence of 5 MAbs epitopes on the envelope and one on the capsid of the virus. Baculoviral mid-gut gland necrosis showed the specificity of the MAbs produced. For diagnosis 5 different methods were selected. Using Kimura primers for PCR, or MAbs for immunoblot, ELISA or FAT method, in situ hybridization was carried out to show the gene. All these methods detected WSSV in the organ samples of the diseased shrimp but not in healthy one.

• Journal of Microbiology and Biotechnology
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• 제10권2호
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• pp.215-220
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• 2000

Abstract White spot disease (WSD), resulting in more than 90% mortality of aquacultured penaeid shrimp, has been reported off the southern and western coasts of Korea since 1993. The pafuogen of WSD has been identified as being a virion wifu an envelope around a central nucleocapsid, and with an average size of 167 nm in diameter and 375 nm in length. In the present study, an in situ hybridization technique was developed as a rapid. sensitive, and specific diagnostic assay for the WSD viros infection in shrimp. Furthermore. the pathological changes ofWSD, in shrimp experimentally infected with WSD viroses. were investigated. Using a biotinylated 643 bp probe obtained from a peR using primers specific to the rod-shaped virus of Penaeus japonicus (RV-PJ), positive signals were detected in both naturally and experimentally infected shrimps. The in situ hybridization revealed positive reactions in the nuclei of the stromal matrix cells in the lymphoid organ, epithelia of the gills, foregut. epidermis, and hematopoietic cells of the interstitial tissues, suggesting the presence of WSD virus. Tills result indicates that the in situ hybridization method can be useful for a rapid and sensitive detection of WSD viruses in shrimp.shrimp.

• 한국식품과학회지
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• 제24권1호
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• pp.14-24
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• 1992

페기물로부터 얻어지는 보리새우(Penaeus japonicus) 껍질과 단백질이용의 전망성이 좋은 antarctic krill(Euphasis superba)을 시료로 하여, chitin의 산업적 이용을 위한 기초연구로서, 보다 효율적인 chitin의 추출조건을 설정하고, 새로운 방법으로 추출한 chitin들의 물리적, 화학적 성질들을 비교하였다. 본 연구에서 선정된 추출 방법으로 chitin을 추출한 결과 보리새우의 껍질을 출발물질로 한 정제 chitin은 순백색의 powder로 얻어졌으며, 정제 chitin의 질소함량 및 ash함량은 각각 6.64%와 0.4%로 나타났다. krill의 chitin의 경우에는 6.35%의 질소함량과 0.4%의 ash함량을 나타내었다. 고유점도를 측정하여 formic acid 용액계에서 구한 정제 chitin의 분자량은 krill의 경우 $1.56{\times}10^{5}$, 보리새우의 경우 $1.78{\times}10^{5}$, Sigma C 3641이 $0.18{\times}10^{5}$으로 나타났으며, N-acetylglucosamine의 중합도는 krill의 경우 약 750, 보리새우의 경우 약 850이었다. 본 연구의 추출방법으로 정제된 chitin은 비교적 아세틸화도가 큰 것으로 확인되었고, 추출후의 아미노산 잔존량 중에서 methionine이 많이 남아있는 것이 특징으로 나타났다.