• The Microorganisms and Industry
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• v.20 no.1
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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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• v.10 no.4
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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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• v.26 no.12
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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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• v.34 no.5
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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.

• Microbiology and Biotechnology Letters
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• v.50 no.1
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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.

• Journal of the Korean Chemical Society
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• v.41 no.9
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• pp.483-487
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• 1997

The whole cells of Chromobacterium chocolatum was immobilized in the matrix of polyacrylamide and then used for the hydrolysis of dimethyl-cis-1,3-dibenzyl-2-oxoimidazolidine-4,5-dicarboxylate. This hydrolysis yielded the optically active monoester ( > 96% ee) which is useful as an synthetic intermediate of (+)-biotin. We have studied the optimum condition of hydrolysis by using immobilized cells under variable concentration of substrate, reaction time and pH levels. The activity of lipase in immobilized cell was retained for longer than 4 weeks. The best conversion yield of product was obtained when 2 g of wet cell was immobilized and then reacted with 200 mg of substrate at pH 7.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.3
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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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• v.14 no.3
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• pp.259-263
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• 1999

Fish oil was hydrolyzed with Aspergillus oryzae lipase, Lipolase-100T. The hydrolysis characteristics of Lipolsae-100T were investigated. Lipolase-100T showed 1,3-positional specificity which hydrolyzed acyl chains combined on the 1 or 3 position of triglyceride into free fatty acids. Lipolase-100T represented another property that the saturated fatty acids composing the triglyceride were hydrolyzed more easily that the polyunsaturated fatty acids(PUFAs). n-3 PUFAs, such as C16:4, C20:5 and C22:6, were hardly hydrolyzed, so that the concentrations of those in the mixture of glycerides were increased according to hydrolysis time. Especially docosahexaenoic acid(DHA), C22:6 showed the highest increase in the concentration. This result explained that n-3 PUFAs were combined on 2-position of triglyceride. When the hydrolysis of fish oil with Lipolase-100T 0.4 wt% was performed for 120 hr, n-3 PUFAs wt% was increased to 50 wt% in the mixture of glycerides. This result was obtained due to the 1,3-positional specificity of Lipolase-100T and positional specificity of n-3 PUFAs.

• BMB Reports
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• v.36 no.4
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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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• v.18 no.2
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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.