• 제목/요약/키워드: Shrimp protease

검색결과 26건 처리시간 0.022초

저염 새우젓 제조를 위한 최적 숙성직전의 감마선 조사시 화학적 품질변화 (Changes of Chemical Properties in Processing of Low Salted and Fermented Shrimp Using Gamma Irradiation immediately before Optimum Fermentation)

  • 이경행;안현주;이철호;김영지;변명우
    • 한국식품과학회지
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    • 제32권5호
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    • pp.1051-1057
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    • 2000
  • 관능적 품질이 우수하고 저장성을 향상시킨 저염 새우젓 개발을 위해 감마선 조사기술을 이용하였다. 식염농도를 15% 및 20%로 조절한 새우젓을 제조하여 $15^{\circ}C$에서 발효시키면서, 최적 숙성기에 도달하기 직전 아미노태 질소의 함량이 400mg% 수준에서 5 kGy 및 10 kGy 선량의 감마선을 조사하였으며, 대조구로는 30% 식염농도의 새우젓을 제조하여 저장기간 동안 화학적 품질을 평가하였다. 최적 숙성직전 감마선을 조사한 결과, 감마선 조사직후 아미노태 질소, 휘발성 염기태 질소, trimethylamine 및 효소활성은 감마선 조사에 의한 영향은 나타나지 않았다. 저장기간에 따른 성분의 변화는 식염함량 및 감마선 조사선량이 증가할수록 낮았으며, 효소활성은 발효 4∼5주까지 계속 증가하다가 감소하는 경향으로 대조구와 유사한 활성을 나타내었다. 특히 15% 식염과 10 kGy의 감마선 조사 및 20% 식염과 5 kGy 이상의 감마선을 최적 숙성직전 조사한 새우젓의 경우 젓갈의 화학적 품질지표인 아미노태 질소, 휘발성 염기태 질소, trimethylamine 함량 및 단백질분해 효소활성이 30% 고염농도인 대조구와 비슷한 수준으로, 발효기간 동안 적정수준의 함량 및 활성을 나타내어 양호한 품질특성을 보였다.

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Artemia franciscana cyst의 세포내 산성 Protease (Characterization of Cytosol Acid Protease from Dormant Cyst of Artemia franciscana)

  • 최희선;최경희;류태형
    • 생명과학회지
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    • 제7권3호
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    • pp.228-233
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    • 1997
  • Artemia franciscana의 cyst에서 protease를 정제하가 위해 세포를 파쇄하여 원심 분리한 후 상등액을 회수하였다. 그상등액에서 40-60% 황산암모늄을 첨가하여 침전시켜서 염을 제가한 후, Sphadex G-200 및 DEAE-Sephadex A-50 column chromatography를 하여 정제한 후 본 효소의 특성을 조사한바 그 특성은 아래와 같았다. 정제 과정을 거치는 동안, 비활성은 13.64배 증가하였고, 수율은 7%였다. 그리고 이효소는 pH 6에서는 안정하였으나, pH 8이상에서는 대부분의 활성이 실활 되었고, 최적 pH는 3.0이었다. 따라서 이 효소는 전형적인 산성 pro-tease로 판정되었다. 본 효소는 60$^{\circ}$C이상의 온도에서 대부분 실활 되었고, 최적 활성 반응 온도는 35$^{\circ}$C였다. 금속 이온의 영향을 알아본 결과, $Cu^{++}$, Z$Zn^{++}$, $Fe^{++}$가 효소의 활성을 저해하였고, 중금속 chelator인 EDTA는 반대로 효소 활성을 증가시켰다. 단백질분해효소에 특이적인저해제를 첨가하여 실험한 결과 thiol protease ingibitor인 antipain, chymostatin, leupeptin, E-64, iodoacetate등에 효과적으로 효소활성이 저해받으므로 본 효소는 acid thiol protease라 판정했다.

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Purification and Characterization of Trypsins Affecting on the Autolysis of Shrimp, Penaeus japonicus

  • KIM Hyeung-Rak;KIM Doo-Sang;AHN Chang-Bum;PYEUN Jae-Hyeung
    • 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.

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Comparative Biochemical Properties of Proteinases from the Hepatopancreas of Shrimp. -II. Purification of Trypsin from the Hepatopancreas of Penaeus orientalis-

  • Oh Eun-Sil;Kim Doo-Sang;Jung Kyoo-Jin;Pyeun Jae-Hyeung;Heu Min-Soo;Kim Hyeung-Rak
    • Fisheries and Aquatic Sciences
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    • 제1권2호
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    • pp.209-215
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    • 1998
  • Trypsin-like enzyme was purified from shrimp hepatopancreas through Q-Sepharose ionic exchange, benzamidine Sepharose-6B affinity, and Superdex 75 gel chromatography. Purity of trypsin-like enzyme was increased 69-fold with $44\%$ yield. The enzyme consisted of a single polypeptide chain with a molecular weight (M.W.) of 32 kDa judged by sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme was completely inactivated by serine enzyme inhibitors such as soybean trypsin inhibitor (SBTI), tosyl-L­lysine chloromethyl ketone (TLCK), and leupeptin. However, the enzyme was not affected by tosyl-L-phenylalanine chloromethyl ketone (TPCK) which is a chymotrypsin specific inhibitor. The enzyme had no activity against benzoyl-tyrosine ethyl ester (BTEE) which is a chymotrypsin specific substrate. The enzyme showed high activity on the carboxyl terminal of Phe, Tyr. Glu, Arg, and Asp. However. no activity was detected against the carboxyl terminal of Pro, Trp, Cys, Gly, Val, and Ala.

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사료 내 Silymarin의 첨가가 흰다리새우(Litopenaeus vannamei)의 성장, 사료효율, 비특이적 면역력 및 항산화력에 미치는 영향 (Effects of Dietary Silymarin on Growth Performance, Feed Utilization, Innate Immunity and Antioxidant Capacity of Pacific White Shrimp Litopenaeus vannamei)

  • 신단비;;김한세;윤관식;이경준
    • 한국수산과학회지
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    • 제55권6호
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    • pp.886-893
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    • 2022
  • This study was conducted to evaluate the effects of dietary silymarin supplementation on the growth performance, feed utilization, innate immunity and antioxidant capacity of Pacific white shrimp Litopenaeus vannamei. Four experimental diets were formulated to contain 0, 0.025, 0.05 and 0.1% silymarin (designated as Con, S0025, S005 and S01, respectively). Triplicate groups of shrimp (initial body weight: 0.70 g) were fed each of the diets for 6 weeks. After the feeding trial, weight gain and specific growth rate were significantly higher in silymarin-supplemented groups compared to Con group. Dietary silymarin significantly enhanced protein efficiency ratio of S01 group and reduced feed conversion ratio of S005 and S01 groups. Phenoloxidase and anti-protease activities were significantly higher in S01 group compared to Con group. Glutathione peroxidase and catalase activities were significantly higher in silymarin-supplemented groups compared to those of Con group. The results of this study indicate that dietary silymarin could improve the growth performance, feed utilization, innate immunity and antioxidant capacity of Pacific white shrimp. The optimum level of silymarin in diet for Pacific white shrimp is suggested to be ≥0.025%.

시판식품에서 분리된 단백분해성이 강한 Streptococcus sp.의 특성 (Characterization of Proteolytic Streptococcus sp. Isolated from Market Foods)

  • 장동석;이종선
    • 한국수산과학회지
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    • 제16권3호
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    • pp.225-230
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    • 1983
  • 본 연구는 단백질 분해성이 강한 세균을 분리하고 그 균의 특성과 균이 생성하는 효소의 성질을 알기 위하여 시판식품 즉 ground beef, cooked shrimp meat, perch fillet, oyster meat, beef with textured vegetable protein, fish digest 등에서 세균을 분리하였다. 분리된 740균주중에서 $30.8\%$에 해당하는 228균주가 단백질 분해성이 있었으며 이 중에서 단백질 분해성이 제일 강한 균주는 Streptococcus sp.였다. 본 균주는 배지에 $KH_{2}PO_4\;0.15\%,\;K_{2}HPO_4\;0.4\%$를 첨가하여 $37^{\circ}C$에서 6시간 배양했을 때 maximum growth에 도달하였고 균체외 단백질 분해효소의 활성은 배양 7시간경에 최고에 달하였다. 그리고 본 Streptococcus sp.가 생성한 균체외 단백분해효소는 EDTA나 o-phenanthroline에 강한 조해작용을 받고 phenylmethylsulfonylfluoride나 p-hydroxymercuribenzoate에 영향을 받지 않는 metal-chelator sensitive protease임을 알 수 있었다.

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새우젓에서 alkaline pretease의 정제 및 특성 (Purification and Characterization of Alkaline Protease from saewoo-jeot, salted and fermented shrimp (Acetes japonicus))

  • 남은정;오세욱;조진호;김영명;양차범
    • 한국식품과학회지
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    • 제30권1호
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    • pp.82-89
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    • 1998
  • 새우젓에서 protease를 추출, 정제하여 이의 효소학적 특성을 조사하였다. 새우젓 protease를 추출, 전기투석으로 탈염, ammonium sulfate로 단백질을 분획 시킨 후 Sephadex G-100 column chromatography와 DEAE-cellulose column chromatography를 행하여 정제하였으며 정제 효소는 전기영동상 단일 band로 나타났으며 분자량은 24 kDa, 수율은 14%, 비활성역가는 8.4 unit/mg, 정제배수는 9.8이었다. 정제효소의 최적 pH는 8.0이었고 $pH\;7.0{\sim}10.0$의 범위에서 안정하였다. 단백질 분해 효소 활성의 최적 온도는 $40^{\circ}C$이었고 $30{\sim}60^{\circ}C$의 온도 범위에서 안정성을 나타내었다. 기질에 대한 특이성으로 합성기질인 BAPNA, TAME에는 활성을 보였으며 hammersten casein을 기질로 사용하였을때의 Km값은 $5.1{\times}10^{-7}\;M$이었다. 금속 이온의 영향으로는 $M^{++}$만이 활성이 증가되었고 다른 금속 이온들에 의해서는 저해되었다. 저해제의 효과에서는 STI차 TLCK에 의해 현저하게 저해되었다. 이상의 성질에서 새우젓에서 분리된 protease는 serine계의 trypsin-like enzyme으로 추정되었다.

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Protease의 전처리에 의한 새우껍질로부터 키틴의 분리와 정제 (Isolation and Purification of Chitin from Shrimp Shells by Protease Pretreatment)

  • 류병호;이상훈
    • 한국식품과학회지
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    • 제27권1호
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    • pp.6-10
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    • 1995
  • 대롱새우껍질로부터 Neutrase처리로 단백질을 제거하고 0.1 M EDTA 2Na로 무기질을 제거하여 키틴을 분리 정제하였다. 키틴의 정제시 Neutrase 3 mg/ml을 첨가하여 pH 6.0, $50^{\circ}C$에서 처리하였을 때 단백질 제거 효과가 제일 좋았다. Neutrase처리에 의한 단백질 제거, 탈 아세틸화도 그리고 칼슘, 인함량은 시판 키틴과 거의 비슷하였다. 분자량은 $1.2{\times}10^{8}$ dalton이었고 키틴의 수율은 28.5%이었다.

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Purification and Characterization of Phocaecin PI80: An Anti-Listerial Bacteriocin Produced by Streptococcus phocae PI80 Isolated from the Gut of Peneaus indicus (Indian White Shrimp)

  • Satish Kumar, Ramraj;Arul, Venkatesan
    • 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.

젓갈 성숙과정(成熟過程)에 있어 Protease 및 Formonitrogen의 변화(變化)에 관(關)한 연구(硏究)(1) (Changes in Protease and Formonitrogen of Salted Fish and Shellfish (1))

  • 서명자
    • Journal of Nutrition and Health
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    • 제6권2호
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    • pp.45-56
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    • 1973
  • Salted fish and shellfish have been widely used in Korea from olden times as side-dishes, although the processes and methods of pickling have varied depending on localities. The common raw materials for these subsidiary food articles include anchovy, shrimp, yellow corvina, oysters, octopus, top-shell, shellfish, pollack roe and pollack intestines. It must be pointed out here, however, that the salted stuffs now marketed locally are highly unscientific and unsanitary in the way they are processed and sold, and this has prompted this writer to undertake a study on these native food articles. The following findings have been obtained from this study on the changes in Formonitrogen and Protease Activity, effected by the density of salt and the degree of storing temperature, of the pickles of cedfish gills, codfish intestines, pollack intestines, shellfish, oysters, cuttle fish and octopus. 1) Codfish Gills The Protease Activity of the pickled codfish gills was greater in the groups of lesser doses of salt and higher degrees of storing temperature. The same was true in the case of Formonifrogen, too. The Formonitrogen of the pickled codfish gills was larger in the groups of lesser salt and higher teimperature. 2) Codfish Intestines The amount of Formonitrogen of the pickled codfiah intestines became greater, as time went by, in the groups of lesser salt than those of larger doses of salt, with the speed of its formation getting faster as the storing temperature rose from $5^{\circ}C$ to $15^{\circ}C$ and $30^{\circ}C$. The Protease Activity was also greater in the groups of lesser salt and higher temperature. The group, stored at 10% salt and $30^{\circ}C$, rotted in five days. 3) Pollack Intestines The amount of Formonitrogen of the pickled pollack intestines was greater in the groups of lesser amount of salt and higher degrees of storing temperature. The Protease Activity of the pickled pollack intestines began decreasing from the 11th day after the pickling in the groups stored at colmparatively high degrees of temperature$(15^{\circ}C-30^{\circ}C)$, while that of the group stored at $5^{\circ}C$ kept rising. The effects of the amount of salt were little. The group stored at 15% salt and $30^{\circ}C$ started rotting on the 13th day while that stored at $30^{\circ}C$ decayed on the 7th day. The group stored at 20% salt and $30^{\circ}C$ rotted on the 9th day. 4) Oysters The amount of Formonitrogen of the pickled oysters became greater as the storing temperature rose and the doses of salt were lowered. The Protease Activity was not affected at any measurable degree by the density of salt in the group stored at $5^{\circ}C$, but became greater as the storing temperature rose to $15^{\circ}C$ and $30^{\circ}C$. The group stored at 10% salt and $30^{\circ}C$ rotted on the 5th day while that stored at 20% salt and $30^{\circ}C$ on the 13th day. 5) Shellfish The amount of Formonitrogen of the pickled shellfish became greater, as time went by, it the groups of lower consistency of salt than the groups of higher density of salt, although the decay of the former groups was faster than the latter groups. The density of salt best fitted for the pickling appeared to be about 20% with the storing temperature to be $15^{\circ}C$, at which the pickled stuff became most tasty on the 7th day. The oysters stored in three groups at $5^{\circ}C$, $15^{\circ}C$ and $30^{\circ}C$ respectively showed the greatest Protease Activity alike at 0% of salt, but the activity declined as the density of salt increased. The Protease Activity of each group rose for the first 11 days after the pickling, but began declining from the 13th day onward, with the groups of higher temperature retaining higher Protease Activity than the groups of lower temperature. 6) Cuttlefish Both the amount of Formonitrogen and the degree of Protease Activity of the pickled cuttlefish were greater in the groups of lower density of salt and higher degree of storing temperature. The oysters pickled at 10% salt and $15^{\circ}C$ degenerated on the 13th day while that of 10% salt and $30^{\circ}C$ deteriorated on the 7th day. 7) Octopus Both the Formonitrogen and the Protease Activity of the pickled octopus were greater in the groups of lower density of salt, but as time went by, the Protease Activity in all groups dwindled after a climbing. In general, the Formonitrogen and the Protease Activity of the pickled oysters became greater as the storing temperature got higher. One group stored at 10% salt and $15^{\circ}C$ rotted in 13days while another group stored at $30^{\circ}C$ decayed in 7 days.

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