• Fisheries and Aquatic Sciences
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• 제25권4호
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• pp.231-242
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• 2022

Effect of different concentrations of hypotaurine (HTU) on melanosis and quality of shrimps during 10 d storage in ice were studied. During refrigeration, the total plate count and total volatile basic nitrogen of shrimps treated with 20 g/L HTU were the lowest, and the hardness and microstructure were the best. Moreover, the score of melanoses, pH and total bile acid of shrimps treated with 20 g/L HTU were also low. Sensory evaluation showed that HTU treatment could make the shelf life of shrimps 3-4 days longer compared with the control. Based on the above physical and chemical indexes, 20 g/L HTU showed great potential as a safe inhibitor in the treatment of shrimps' melanosis.

• 한국어병학회지
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• 제36권2호
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• pp.361-368
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• 2023

Juveniles of the white leg shrimp Litopenaeus vannamei (Weight 0.18±0.08 g) were exposed to nitrite-N at 0, 25, 50, 100, 200 and 400 mg/L for 72 hours, and the lethal concentration, heamolymph and genes regulation were evaluated. The lethal concentration 50 (LC₅₀) of L. vannamei exposed to nitrite-N was 141.2 mg/L at 25℃ and 33 psu. In Total protein, total cholesterol, and BUN in heamolymph temporarily increased after the start of the experiment and then stabilized, but glucose, an indicator of stress, decreased over time in the entire experimental group, and creatines, an indicator of tissue damage, decreased with nitrite concentration until the first 12 hours. The genes of immune-related showed that masquerade-like serine proteinase(Mas) increased at 50 and 400 ppm for 24 hours, and then gradually decreased depending on concentration. In the case of prophenoloxidase, it was highest at 400 ppm for 40 hours, and other genes(Ras-related nuclear protein, Masquerade-like serine proteinase, proPO-activating enzyme) showed a response for 48 hours and then gradually decreased. The results of this study indicate that exposure to nitrite can affect the survival and hematological physiology of L. vannamei.

• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1393-1400
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• 2009

A bacteriocin-producing strain PI80 was isolated from the gut of Penaeus indicus (Indian white shrimp) and identified as Streptococcus phocae PI80. The bacteriocin was purified from a culture supernatant to homogeneity as confirmed by Tricine SDS-PAGE. Reverse-phase HPLC analysis revealed a single active fraction eluted at 12.94 min, and MALDI-TOF mass spectrometry analysis showed the molecular mass to be 9.244 kDa. This molecular mass does not correspond to previously described streptococcal bacteriocins. The purified bacteriocin was named phocaecin PI80 from its producer strain, as this is the first report of bacteriocin production by Streptococcus phocae. The bacteriocin exhibited a broad spectrum of activity and inhibited important pathogens: Listeria monocytogenes, Vibrio parahaemolyticus, and V. fischeri. The antibacterial substance was also sensitive to proteolytic enzymes: trypsin, protease, pepsin, and chymotrypsin, yet insensitive to catalase, peroxidase, and diastase, confirming that the inhibition was due to a proteinaceous molecule (i.e., the bacteriocin), and not due to hydrogen peroxide or diacetyl. Phocaecin PI80 moderately tolerated heat treatment (up to $70^{\circ}C$ for 10 min) and resisted certain solvents (acetone, ethanol, and butanol). A massive leakage of $K^+$ ions from E. coli $DH5\alpha$, L. monocytogenes, and V. parahaemolyticus was induced by phocaecin PI80, as measured by Inductively Coupled Plasma Optical Emission Spectrometry (ICPOES). Therefore, the results of this study show that phocaecin PI80 may be a useful tool for inhibiting L. monocytogenes in seafood products that do not usually undergo adequate heat treatment, whereas the cells of Streptococcus phocae PI80 could be used to control vibriosis in shrimp farming.

• Asian-Australasian Journal of Animal Sciences
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• 제25권8호
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• pp.1184-1189
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• 2012

White spot syndrome virus (WSSV) is one of the major viral pathogens affecting shrimp aquaculture. Four proteins, WSSV199, WSSV 222, WSSV 249 and WSSV 403, from WSSV are predicted to encode a RING-H2 domain, which in presence of ubiquitin conjugating enzyme (E2) in shrimp can function as viral E3 ligase and modulate the host ubiquitin proteasome pathway. Modulation of host ubiquitin proteasome pathway by viral proteins is implicated in viral pathogenesis. In the present study, a time course expression profile analysis of WSSV Open Reading Frame (ORF) 199 and Penaeus monodon ubiquitin conjugating enzyme (PmUbc) was carried out at 0, 3, 6, 12, 24, 48 and 72 h post WSSV challenge by semi-quantitative RT-PCR as well as Real Time PCR. EF1${\alpha}$ was used as reference control to normalize the expression levels. A significant increase in PmUbc expression at 24 h post infection (h.p.i) was observed followed by a decline till 72 h.p.i. Expression of WSSV199 was observed at 24 h.p.i in WSSV infected P. monodon. Since the up-regulation of PmUbc was observed at 24 h.p.i where WSSV199 expression was detected, it can be speculated that these proteins might interact with host ubiquitination pathway for viral pathogenesis. However, further studies need to be carried out to unfold the molecular mechanism of interaction between host and virus to devise efficient control strategies for this chaos in the shrimp culture industry.

• 한국수산과학회지
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• 제53권6호
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• pp.851-860
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• 2020

Shrimp in seasoned soy sauce (S-SS) is a popular seafood product in Korea, but it could be potentially hazardous; thus, this study was conducted to investigate its safety. Commercial S-SS were collected and analyzed for pH, volatile basic nitrogen (VBN), hygenic indicator microorganisms (viable cell count, coliforms, and Escherichia coli), food poisoning bacteria (Staphylococcus aureus, Vibrio parahaemolyticus, and Listeria monocytogenes), preservatives (dehydroacetic acid, sorbic acid, benzoic acid, and its salt, parahydroxybenzoate), tar colorants, and sensory properties. Domestic and foreign standards were also investigated for S-SS. Commercial S-SS ranged from to 6.2-7.3 for pH, 13.7-39.1 mg/100 g for VBN, and 4.6-6.9 log CFU/g for viable cells. The coliforms and E. coli of commercial S-SS were from ND to 3.4 log CFU/g and negative, respectively. Food poisoning bacteria, preservatives, and tar colorants were not detected in commercial S-SS. Only the coliform count and presence of E. coli in commercial S-SS exceeded the set standards of vietnam, while all items were within domestic and foreign standards.

• 미생물학회지
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• 제44권1호
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• pp.49-55
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• 2008

흰반점 바이러스(white spot syndrome virus, WSSV)는 양식산 새우에 감염하여 대량폐사를 일으키는 전염성이 매우 강한 병원성 바이러스이다. 본 연구에서는 강화도에 위치한 대하(Fenneropenaeus chinensis) 양식장의 양식수와 양식장으로 유입되는 해수에서 WSSV를 막여과법을 이용하여 농축하였으며, 새롭게 디자인한 primer와 Taqman probe를 사용하여 정량 실시간 PCR (quantitative real-time PCR, QRT-PCR)을 적용하여 WSSV를 정량하였다. 농도표준을 사용한 QRT-PCR 결과, 제작된 primer와 probe를 이용하여 WSSV가 정확하고 민감하게 검출됨을 확인하였다. 해수에 존재하는 WSSV와 물리화학적, 생물학적 환경요인간의 상관관계를 도출하기 위하여 양식수와 해수 유입수에서 대하 양식기간인 2007년 6월부터 9월까지 총 8회에 거쳐 다양한 환경요인을 분석하였다. 양식수 1L에 존재하는 WSSV의 양은 3,814-121,545 copy였으며, 이는 분원성 enterococci ($r^2=0.9$, p=0.02), 엽록소${\alpha}$ ($r^2=0.8$, p=0.03), 생화학적 산소요구량($r^2=0.8$, p=0.07)과 상관관계를 나타내었다. 결론적으로 본 연구에서 정립된 WSSV의 농축법 및 QRT-PCR 방법은 해수에 존재하는 WSSV를 정량하는데 효과적이었으며, 해수에 존재하는 WSSV의 양은 물리화학적 환경요인보다 생물학적 환경요인과 밀접한 관련을 보였다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권1호
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• pp.82-87
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• 2001

A feeding trial was conducted to evaluate the effects of replacing fish meal (FM) with ensiled shrimp by-product (ESB) in a cassava root meal and rice bran-based diet on the performance and carcass characteristics of growing pigs. Thirty six crossbred (Large White$\times$Mong Cai) pigs, with an average initial BW of 19.4 kg, were randomly allocated to one of three different dietary treatments in which the crude protein of the FM was replaced with 0, 50 or 100% ESB. The animals were fed restrictedly and at the end of the experiment at a BW of about 90 kg, 6 representative animals in each treatment group were slaughtered for carcass quality evaluation. Animal growth performance and daily feed intake were significantly reduced (p<0.05) by the inclusion of shrimp by-products in the diets, whereas feed conversion ratios and carcass measurements were not significantly affected (p>0.05). Daily weight gains of the pigs fed the 100% FM diet and 50% ESB diet were significantly (p<0.05) higher than those of pigs fed the 100% ESB diet. In conclusion, from an economical as well as performance point of view, ESB can replace 50% of the crude protein of FM in cassava root meal and rice bran-based diets for growing pigs with a low genetic growth potential.

• 센서학회지
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• 제30권3호
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• pp.154-164
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• 2021

RAS(Recirculating aquaculture system) 방식 또는 바이오플락 기술를 사용한 흰다리 새우의 육상 양식을 통해서 새우 개체의 생존율과 고밀도 생산율을 향상시키기 위한 양식의 원리 및 장치 구성, 국내외 수질 모니터링 센서, 현재의 양식 모니터링 시스템의 문제점 파악 및 미래의 양식 모니터링을 위한 대책을 분석 하였다. 흰다리 새우 양식을 위해서는 수조별 온도, pH, DO, 염도 측정이 기본적으로 필요하며, 암모니아성 질소, 질산성 질소, 아질산성 질소, 생장 관리를 위한 이온성 물질의 측정이 필요하다. 특히 센서재질에 있어서는 SUS304도 부식이 되는 고염도 환경에서 견딜수 있어야 하며, 고탁도 및 부유물질에 의한 생물 부착에 견딜 수 있는 센서가 사용되어야 한다. 또한 내구성 및 측정값 신뢰도, 가격 경쟁력 있는 센서 및 시스템 공급이 필요하다. 바이오플락 양식 환경에서는 고염분, 고부유물 환경에서 견딜 수 있는 센서의 내구성과 데이터 안정성, 신뢰도가 무엇보다 중요하다. 향후 흰다리 새우 및 수산 양식을 위한 최적 양식환경을 확보하기 위해서는 양식 생육 환경 현장의 수질을 측정하고 적정 환경을 결정하며, 자동제어 시스템을 이용하여 제어하고 축적된 데이터를 활용 및 분석하여 지능적으로 관리하는 기술을 개발하는 것이 필요하다.

• 한국수산과학회지
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• 제55권6호
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• pp.817-826
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• 2022

This study was conducted to determinean optimal soaking solution for inhibiting the texture softening of shrimp Litopenaeus vannamei pressured at high temperature (S-P/HT) in a retort, and also to optimize concentrations of 0.5% calcium chloride (CC) and 5.0% potato starch (PS) for preparation of a mixed solution (MS) and soaking time (ST) in the MS. On the basis of the results of expressible drip (4.6%), water holding capacity (95.1%), hardness (18.4 N/cm²) and sensory texture (7.2 score), the MS was found to be the optimal soaking solution for inhibition of texture softening under S-P/HT conditions, The concentrations of CC (X₁, %), PS (X₂, %), and ST (X₃, min) were selected as independent variables, and hardness (Y₁), springiness (Y₂) and sensory texture (Y₃) were selected as dependent variables. The optimal conditions of X₁, X₂, and X₃ were 0.51%, 6.34%, and 364 min, respectively. Under the optimal conditions, the experimental values of Y₁, Y₂ and Y₃ were 18.3±0.8 N/cm², 4.4±0.3 mm and 7.7±0.2, respectively, which did not diffr significantly from the predicted values (P>0.05). In conclusion, the optimized models of X₁, X₂, and X₃ for the preparation of S-P/HT using CC-PS were suitably fitted.

• 한국어병학회지
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• 제25권3호
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• pp.271-277
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• 2012

2012년 5월에서 11월 사이에 우리나라 넙치, 조피볼락, 무지개송어, 뱀장어, 흰다리새우, 전복 양식장에서 발생하는 폐사피해를 표본조사를 통해 모니터링하였다. 조사의 방식은 해당 양식장과 거래하고 있거나 관계를 맺고 있는 전국의 수산질병관리사 조사요원의 직접 현장 방문을 통한 면접과 표준 매뉴얼을 통한 진단을 통하여 실시하였다. 조사기간 중 넙치 양식장에서는 총 27.9%의 누적 피해율을 보여주었고, 이중 스쿠티카병, 연쇄구균병, VHS, 비감염성 원인에 의한 폐사, 비브리오병, 활주세균병의 순으로 폐사피해가 높은 것으로 나타났다. 조피볼락 양식장에서는 13.6%의 누적 피해율을 보여주었고, 아가미 흡충병, 연쇄구균병, 비브리오병, 활주세균병, 비감염성 원인에 의한 폐사 순의 폐사피해가 나타났다. 무지개송어의 경우 총 17.1%의 피해율을 기록하였고, 비감염성 원인에 의한 폐사와 백점병이 주된 폐사 원인으로 집계되었다. 뱀장어의 경우 비교적 낮은 0.6%의 피해율을 기록하였으며, 에드워드병, 백점병, 아가미흡충병이 주된 피해요인이었다. 흰다리새우는 71.2%의 피해율을 보였으며, 대부분 비감염성 원인에 의한 폐사으로 집계되었고, 바이러스성 흰반점병도 12.5%의 피해를 준 것으로 나타났다. 전복의 경우 10.7%의 피해율 모두가 비감염성 원인에 의한 폐사 피해인 것으로 조사되었다.