• 한국연초학회지
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• 제20권1호
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• pp.80-86
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• 1998

Changes in activity and classification of esterase isozymes during the tire cycle or Plodia inteipunctella (Hiibner) were investigated by the native polyacrylamide gel electrophoresis. The stage specificity in esterase activity and isozyme pattern was observed throughout the larvalpupal-adult transformation. The activity esterase was highest at the 3-day old adult stage, and the lowest level at the prepupal stage. A total of 12 esterase bands were identified throughout the development, and the bands showing high enzyme activity was observed in the middle part of gel. Twelve esterases on the basis of inhibition by the three types of inhibitors (organophosphates, eserine sulfate and sulfhydryl reagents) were classified into three class, namely, carboxylesterase (CE), arylesterase (ArE) and cholinesterase (ChE), and these classes contained 7, 3 and 2 isozymes, respectively.

• 한국동물학회지
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• 제33권3호
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• pp.330-336
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• 1990

배추흰나비의 변태에 따른 esterase의 활성변화 및 zymogram pattern의 변화를 조사하였으며 5령말 유충으로부터 3개의 esterase를 순수 분리하였다. Esterase의 활성은 5령초에서 5령말에 이르는 동안 급격히 증가하여 5령말에서 최대의 활성이 나타났으며 전기영동의 결과 whole body와 중장내 esterase band의 수나 강도는 5령말에서 최대로 나타났다. Gel filtration과 ion-exchange chromatography 및 preparative electorphoresis를 통해 정제된 각 esterase의 최종순도는 약 30-60배였다.

• Applied Biological Chemistry
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• 제40권6호
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• pp.484-489
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• 1997

산분해 대두 단백질로 부터 식품 보존료인 p-hydroxybenzoic acid butyl ester를 분해하고, esterase 활성을 갖는 균주들을 분리, 동정하여 그들의 생육 및 효소 생성 특징을 조사하였다. 분리된 균주들은 전부 Baillus sp. 로 동정되었으며, specific growth rate는 균주에 따라 $0.844{\sim}1.213\;h^{-1}$였으며, esterase activity 는 Baillus sp. KB8 균주가 222 mU/ml로 대비균주인 B. subtilis ATCC6633의 21 mU/ml보다 10배 높은 활성을 보였으나 p-hydroxybenzoic acid butyl ester 분해 활성도는 $5.4{\sim}8.1\;mU/ml$로 균주에 따른 큰 차이는 볼 수 없었다. Baillus sp. KB8 균주의 배양시 NaCl 첨가는 생육을 저해시키며, esterase의 세포외 축적과 세포내 합성을 억제시키는 것으로 나타났으며, 특히 NaCl 첨가 농도의 증가는 세포외 축적을 더 억제시키는 것으로 나타났다. 플라스크 배양실험 결과 Baillus sp. KB8 균주의 효소 생성은 생육이 stationary phase 이후 점차 증가하여 배양 64시간에 420 mU/ml를 생성하였다. 온도에 대한 esterase의 활성은 $50^{\circ}C$에서 30분간 실활없이 유지되었으나 $70^{\circ}C$에서는 전부 실활되었다. $60^{\circ}C$와 $65^{\circ}C$ 에서의 효소 활성은 노출 시간에 따라 지수적인 실활 경향을 보여 3시간 후 $60^{\circ}C$에서 76%, $65^{\circ}C$에서는 3%의 잔존 효소활성을 보였다.

• BMB Reports
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• 제40권4호
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• pp.588-594
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• 2007

A novel hot spring thermophile, Anoxybacillus gonensis A4 (A. gonensis A4) was investigated in terms of capability of tributyrin degradation and characterization of its thermostable esterase activity by the hydrolysis of p-nitrophenyl butyrate (PNPB). It was observed that A. gonensis A4 has an esterase with a molecular weight of 62 kDa. The extracellular crude preparation was characterized in terms of substrate specificity, pH and temperature optima and stability, kinetic parameters and inhibition/activation behaviour towards some chemicals and metal ions. Tributyrin agar assay showed that A. gonensis A4 secreted an esterase and $V_{max}$ and $K_m$ values of its activity were found to be 800 U/L and 176.5 ${\mu}M$, respectively in the presence of PNPB substrate. The optimum temperature and pH, for A. gonensis A4 esterase was $60-80^{\circ}C$ and 5.5, respectively. Although the enzyme activity was not significantly changed by incubating crude extract solution at $30-70^{\circ}C$ for 1 h, the enzyme activity was fully lost at $80^{\circ}C$ for same incubation period. The pH-stability profile showed that original crude esterase activity increased nearly 2-fold at pH 6.0. The effect of some chemicals on crude esterase activity indicated that A. gonensis A4 produce an esterase having serine residue in active site and -SH groups were essential for its activity.

• 한국환경농학회지
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• 제9권2호
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• pp.97-103
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• 1990

담수토양중 Diazinon과 Dursban의 분해에 미치는 Monooxygenase 활성과 ${\alpha}$, ${\beta}-esterase$ 활성의 영향을 알아보기 위하여, 실험실 조건에서 항온($30{\pm}1^{\circ}C$)으로 유지하면서 두 약제의 분해율과 두 효소의 활성변화를 측정하였으며, 주요 결과는 아래와 같다. 1. 담수토양중 두 약제의 전체 분해율 중 미생물에 의한 분해율은 5일과 10일 사이에 Diazinon은 29-38%(1X), 34-24%(3X), Dursban은 18-28%(IX), 18-27%(3X)이었다. 2. M. O.활성은 Diazinon 처리구에서 12시간부터, Dursban처리구에서 3일부터 활성을 나타내었다. 3. ${\alpha}-$보다는 ${\beta}-esterase$활성이 10배정도 높았으며, Dursban처리구는 초기(1일)에 활성이 높았지만, Diazinon 처리구는 후기($5{\sim}8$일)에 활성이 높았다. 4. Diazinon의 분해율과는 M.O. 활성이, Dursban의 분해율과는 ${\beta}-esterase$활성이 각각 2배정도 더 큰 영향을 미치는 것을 알 수 있었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권1호
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• pp.53-56
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• 2000

A thermostable esterase from the hyper thermophilic archaeon Sulfolobus solfataricus was partially purified 590-fold with $16.2\%$ recovery. The partially purified esterase had a specific activity of $29.5\;{\mu}mol\;min^{-1}mg^{-1}$ when the enzyme activity was determined using p-nitrophenyl butyrate as a substrate. The apparent molecular weight was about 100 kDa, while the optimum temperature and pH for esterase were $75^{\circ}C$ and 8.0, respectively. The enzyme showed high thermal stability and solvent tolerance in comparison to its mesophilic counterpart. The enzyme also showed chiral resolution activity for (S)-ibuprofen, indicating that S. solfataricus esterase can be used for the production of commercially important chiral drugs.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권4호
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• pp.367-371
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• 2005

About 3,000 bacterial colonies with esterase activities were isolated from soil samples by enrichment culture and halo-size on Luria broth-tributyrin (LT) plates. The colonies were assayed for esterase activity in microtiter plates using enantiomerically pure (R)- and (S)-2-phenylbutyric acid resorufin ester (2PB-O-res) as substrates. Two enantioselective strains (JH2 and JH13) were selected by the ratio of initial rate of hydrolysis of enantiomerically pure (R)- and (S)-2-PB-O-res. When cell pellets were used, both strains showed high apparent enantioselectivity ($E_{app}>100$) for (R)-2PB-O-res and were identified as Exiguobacterium acetylicum. The JH13 strain showed high esterase activity on p-nitrophenyl acetate (pNPA), but showed low lipase activity on p-nitrophenyl palmitate (pNPP). The esterase was located in the soluble fraction of the cell extract. The crude intracellular enzyme preparation was stable at a pH range from 6.0 to 11.0.

• 대한수의학회지
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• 제4권1호
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• pp.15-17
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• 1964

Scabby burley collected in Kyong Sang Nam Do fed to healthy dogs, age less than 2 years, old and determined the Choline-Esterase Activity in blood of dogs. The results obtained in this investigation are summarized as follows. 1. Choline-Esterase Activity in the blood of dogs fed Scabby barley has been decreased. 2. The poisionous component of the Scabby barley thought to be Anticholinesterase.

• 농약과학회지
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• 제11권2호
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• pp.117-124
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• 2007

포식성 무당벌레(Harmonia axyridis)의 난(卵)을 대상으로 저독성 약제를 선발하기 위해 농약 처리 후 esterase 활성에 대해 조사하였다. 무당벌레의 난에는 3개의 esterase bands가 존재하였고 esterase의 활성에 영향을 주는 살충제(Methidation, Chlorpyrifos, Phenthoate)는 유기인계인 것으로 나타났다. 살균제로는 트리아졸계 계통의 Hexaconazole과 Triflumizole 그리고 피리미딘계의 Nuarimol에서 esterase의 활성 저해가 관찰되었다. 선발된 농약을 바탕으로 무당벌레의 산란율과 부화율을 조사하였다. Esterase에 강한 활성저해를 보였던 농약에서는 산란율과 부화율도 낮게 나타났으며, esterase에 약하게 혹은 전혀 영향을 주지 않았던 농약에서도 정도 차이는 있으나 산란율과 부화율에 영향을 주는 것으로 관찰되었다.

• Journal of Microbiology and Biotechnology
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• 제18권5호
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• pp.889-896
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• 2008

A suitable simple model tested by experiments is required to address complex biological reactions like esterase synthesis by Saccharomyces cerevisiae. Such an approach might be the answer to a proper bioprocessing strategy. In this regard, a logistic model for esterase production from Saccharomyces cerevisiae has been developed, which predicts well the cell mass, the carbon source (glucose) consumption, and the esterase activity. The accuracy of the model has been statistically examined by using the Student's t-test. The parameter sensitivity analysis showed that all five parameters (${\mu}_m$, $K_a$, $X_m$, $Y_{x/s}$, and $Y_{p/x}$) have significant influence on the predicted values of esterase activity.