• 미생물과산업
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• 제20권1호
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• pp.23-27
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• 1994

본고에서는 화학적수법으로 다양한 특이한 기질을 제조하여 여기에 입체특이적 성질(stereospecificity)과 입체선택적 성질(steroselectivity)이 높은 생물학적 방법들 중에서 주로 lipase를 이용한 부제가수분해반응(asymmetric hydrolysis)과 그 역반응인 에스테르화반응(esterification)등을 도입한 chiral building block의 제조와 이를 이용한 곤충 생리활성물질인 pheromone의 합성에 대한 최근의 많은 예들중 상품화를 시도하고 있는 매미나방의 pheromne인 (+)-disparlure에 대하여 간단히 소개하고자 한다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권4호
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• pp.329-333
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• 2005

This study was designed to investigate the stability of a lipase fused with a cellulose­binding domain (CBD) to cellulase. The fusion protein was derived from a gene cluster of a CBD fragment of a cellulase gene in Trichoderma hazianum and a lipase gene in Bacillus stearother­mophilus L1. Due to the CBD, this lipase can be immobilized to a cellulose material. Factors affecting the lipase stability were divided into the reaction-independent factors (RIF), and the re­action-dependent factors (RDF). RIF includes the reaction conditions such as pH and tempera­ture, whereas substrate limitation and product inhibition are examples of RDF. As pH 10 and $50^{\circ}C$ were found to be optimum reaction conditions for oil hydrolysis by this lipase, the stability of the free and the immobilized lipase was studied under these conditions. Avicel (microcrystal­line cellulose) was used as a support for lipase immobilization. The effects of both RIF and RDF on the enzyme activity were less for the immobilized lipase than for the free lipase. Due to the irreversible binding of CBD to Avicel and the high stability of the immobilized lipase, the enzyme activity after five times of use was over $70\%$ of the initial activity.

• Archives of Pharmacal Research
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• 제26권12호
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• pp.997-1001
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• 2003

This paper deals with chiral enzymatic resolution of 4-arylthio-2-butanols by lipase to prepare potential intermediates of $\beta$-lactam antibiotics. Among several lipases employed, lipase P type enzyme gave the highest ee value to prepare (R)-4-arylthio-2-butyl acetate. The enzymatic resolution of phenyl substituted alcohol (6a) using lipase P showed the highest ee value (99.7%) among those of 4-arylthio-2-butanol derivatives. Lipase P mediated hydrolysis of acylester 7a gave also (R)-alcohol 6a selectively. For determination of enantiomeric purity of these enzymatic resolved analytes, liquid chromatographic analysis was performed using two coupled Chiralcel OD and (R,R)-WhelkO chiral column.

• BMB Reports
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• 제34권5호
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• pp.457-462
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• 2001

Using the monomolecular film technique, we compared the interfacial properties of Staphylococcus simulans lipase (SSL) and Staphylococcus aureus lipase (SAL). These two enzymes act specifically on glycerides without any detectable phospholipase activity when using various phospholipids. Our results show that the maximum rate of racemic dicaprin (rac-dicaprin) hydrolysis was displayed at pH 8.5, or 6.5 with Staphylococcus simulans lipase or Staphylococcus aureus lipase, respectively The two enzymes interact strongly with egg-phosphatidyl choline (egg-PC) monomolecular films, evidenced by a critical surface pressure value of around $23\;mN{\cdot}m^{-1}$. In contrast to pancreatic lipases, $\beta$-lactoglobulin, a tensioactive protein, failed to inhibit Staphylococcus simulans lipase and Staphylococcus aureus lipase. A kinetic study on the surface pressure dependency, stereoselectivity, and regioselectivity of Staphylococcus simulans lipase and Staphylococcus aureus lipase was performed using optically pure stereoisomers of diglycerides (1,2-sn-dicaprin and 2,3-sn-dicaprin) and a prochiral isomer (1,3-sn-dicaprin) that were spread as monomolecular films at the air-water interface. Both staphylococcal lipases acted preferentially on distal carboxylic ester groups of the diglyceride isomer (1,3-sn-dicaprin). Furthermore, Staphylococcus simulans lipase was found to be markedly stereoselective for the sn-3 position of the 2,3-sn-dicaprin isomer.

• 한국미생물·생명공학회지
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• 제50권1호
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• pp.71-80
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• 2022

Lipases (triacylglycerol acylhydrolases [EC 3.1.1.3]) are water-soluble enzymes. They catalyze the hydrolysis of fats and oils. A cold-active lipase from marine Bacillus cereus HSS, isolated from the Mediterranean Sea, Alexandria, Egypt, was purified and characterized. The total purification depending on lipase activity was 438.9 fold purification recording 632 U/mg protein. The molecular weight of the purified lipase was estimated to be 65 kDa using sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. The optimum substrate concentration, enzyme concentration, pH, and temperature were 1.5 mM, 100 µl, pH 6 and 10℃, respectively. The lipase was tolerant to NaCl concentrations ranging from 1.5 to 4.5%. The lipase was affected by the tested metal ions, and its activity was inhibited by 16% in the presence of 0.05 M SDS. The application of the cold-active lipase for the removal of an oil stain from a white cotton cloth showed that it is a promising biological agent for the treatment of oily wastes and other related applications. To the best of our knowledge, this is the first report of the purification and characterization of a lipase from marine B. cereus HSS isolated from the Mediterranean Sea.

• 대한화학회지
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• 제41권9호
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• pp.483-487
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• 1997

Chromobacterium chocolatum의 whole cell을 polyacrylamide의 matrix안에 고정화 하였으며 이를 이용하여 dimethyl-cis-1,3-dibenzyl-2-oxoimidazolidine-4,5-dicarboxlyate를 가수분해 하였다. 고정화된 mycelium을 이용하여 가수분해하는 최적조건을 연구하였다. 기질의 농도, 반응시간, 용액의 pH변화에 다른 lipase의 안정성및 반응의 영향을 연구하였다. 고정회된 mycelium의 리파아제의 활동도는 4주이상 지속되었고 wet cell 2g을 고정화 하여 200 mg의 기질을 pH=7의 반응조건에서 반응시켰을 때 최대 수율로 생성물이 얻어졌다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권3호
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• pp.211-214
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• 2006

Immobilized Candida antarctica lipase was used to catalyze the separation of ketoprofen into its components by means of esterification followed by the enzymatic hydrolysis of the ester product. In this study, ketoprofen underwent esterification to ethanol in the presence of isooctane. When the reaction was complete, 58.3% of the ketoprofen had been transformed into an ester. The ketoprofen remaining in solution after the reaction was complete consisted primarily of its S-enantiomer (83.0%), while the 59.4% of the ketoprofen component of the ester consisted of its R-enantiomer. We then subjected the ester product to enzymatic hydrolysis in the presence of the same enzyme and produced a ketoprofen product rich in the R-enantiomer; 77% of this product consisted of the R-enantiomer when 50% of the ester had been hydrolyzed, and 90% of it consisted of the R-enantiomer when 30% of the ester had been hydrolyzed. By contrast, the R-enantiomer levels only reached approximately 42 and 65%, respectively, when 50 and 30% of the racemic ester was hydrolyzed under the same conditions.

• KSBB Journal
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• 제14권3호
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• pp.259-263
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• 1999

물고기 기름에 대한 Aspergillus oryzae 유래의 Lipolase-100T의 가수분해 특성을 규명하였다. Lipolase-100T는 트리글리세라이드의 1과 3의 위치에 작용하여 이 위치에 결합되어 있는 아실 체인을 유리지방산으로 가수분해시키는 1,3-위채특이성을 보였다. 또한 Lipolase-100T는 물고기 기름을 구성하는 다중불포화지방산 보다 포화지방산을 쉽게 가수분해시키는 특성도 나타내었다. 이 특성으로 인하여 가수분해 시간에 따라서 생성되는 글리세라이드 혼합물내의 다중 불포화 지방산중 n-3 PUFAs인 C16:4, C20:5 및 C22:6의 농도는 모두 증가하였으며 특히 C22:6의 농도증가가 가장 뚜렷하였다. 이 결과로부터 물고기 기름을 구성하는 n-3 PUFAs는 트리글리세라이드의 2번 위치에 결합하고 있음을 알 수 있었다. 지방산의 결합위치특이성과 Lipolase-100T 1,3-위치특이성으로 인하여 Lipolase-100T를 반응물의 0.4 wt%사용하여 물고기 기름을 120시간 가수분해 시켰을 때 생성된 글리세라이드 혼합물내의 n-3 PUFAs농도는 50 wt%까지 상승하였다.

• BMB Reports
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• 제36권4호
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• pp.417-420
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• 2003

The present work describes a colorimetric microplate assay for lipase activity based on the reaction between 5,5'-dithiobis(2-nitro benzoic acid) (DTNB) and the hydrolysis product of 2,3-dimercapto-1-propanol tributyrate (DMPTB). Reaction mixtures containing DTNB, DMPTB, and lipase were prepared in microplate wells, and the absorbance at 405nm was recorded after incubation at $37^{\circ}C$ for 30 min. A linear relationship was obtained in the range of 0.1-1 U of lipase activity by this method. The reaction conditions were also optimized for the range of 0.01-0.1 U or 1-10 U. When assaying crude tissue extracts, the reaction of DTNB with non-specific reducing agents created a major source of error. However, this error was corrected by the use of blank samples that did not contain DMPTB.

• Natural Product Sciences
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• 제18권2호
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• pp.116-120
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• 2012

Pancreatic lipase digests dietary fats by hydrolysis, which is a key enzyme for lipid absorption. Therefore, reduction of fat absorption by the inhibition of pancreatic lipase is suggested to be a therapeutic strategy for obesity. We previously reported coumarins and secoiridoids of Fraxinus rhynchophylla as inhibitory constituents on adipocyte differentiation. Further investigation on F. rhynchophylla led to the isolation of lignan derivatives such as lignans (1 - 10), sesquilignans (11 - 14) and coumarinolignans (15 - 17). Among them, coumarinolignans and sesquilignans were first reported from Fraxinus species. Among the constituents isolated, sesquilignans showed the significant inhibition on pancreatic lipase, whereas lignans and coumarinolignans exerted weak effects.