Applications of Lipases

Lipases are being used in several reactions of synthesis for the production of valuable compounds. Biodegradable polymers, like butyl oleate and some polyesters, have been synthesized by esterification and transesterification reactions with lipases 

Some other miscellaneous applications of lipases have bee reported, including their use in diagnostics and biosensors (Hasan et al. 2006). A comprehensive analysis of lipase applications can be found in http //www.au-kbc. org/beta/bioproj2/index. html. 

New applications of lipases are expected to develop vigorously in the forthcoming years in view of its remarkable versatility, selectivity and robustness, which are well appreciated attributes for performing chemical synthesis. In the next section, a novel application of lipase for the selective transesterification of wood sterols will be described. 

Transesterification of the Stanol Fraction of Wood Sterols with Immobilized Lipases 

Pulp and paper industry is quite relevant to Chilean economy. Kraft process for cellulose production is based on the chemical digestion of wood chips with sodium hydroxide and sodium sulfide at high pressure to extract the lignin and recover the 

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Dynamic kinetic resolution enables the limit of 50 % theoretical yield of kinetic resolution to be overcome. The application of lipase-catalyzed enzymatic resolution with in situ thiyl radical-mediated racemization enables the dynamic kinetic resolution of non-benzylic amines to be obtained. This protocol leads to (/f)-amides with high enantioselectivities. It can be applied either to the conversion of racemic mixtures or to the inversion of (5)-enantiomers. 

Chapter 3 describes the application of lipases, proteases and sulfatases for the kinetic resolution of a range of interesting molecules. A selection of dynamic kinetic resolution (DKR) procedures is disclosed in Chapter 4. DKRs are attracting a significant amount of... 

The main current potential application of lipase-catalyzed fat-modification processes is in the production of valuable confectionery fats for instance, alternative methods of obtaining cocoa-butter equivalents by converting cheap palm-oil fats and stearic acid to cocoa-butter-like fats. The reaction is executed in a water-poor medium, such as hexane, to prevent hydrolysis. At least one commercial apphcation exists. Loders Croklaan (Unilever) has an enzymatic interesterification plant in Wormerveer, the Netherlands. Many other new potential applications of lipases have been proposed of which some will certainly be economically feasible. Examples and details can be found in chapter 9 of this book. 

The application of lipases in synthetic biotransformations encompasses a wide range of solvolytic reactions of the carboxyl group, such as esterification, transesterification (alcoholysis), perhydrolysis, and aminolysis (amide synthesis) [103]. Transesterification and amide synthesis are preferably performed in an anhydrous medium, often in the presence of activated zeolite, to suppress unwanted hydrolytic side reactions. CaLB (which readily tolerates such conditions [104,105]), PsL, and PcL are often used as the biocatalyst [106]. 

The resolution of chiral alcohols through lipase-mediated enantioselective acylation (transesterification) is one of the major industrial applications of lipases [50]. Hence, the effects of ionic liquid reaction media on the resolution of various... 

The asymmetric acylation reaction has proven utility in the synthesis of biologically relevant targets. This is demonstrated by the plethora of applications of lipases and esterases in total syntheses [ 1 ]. While these enzymes often display superb selectivities, their application to a broad class of substrates may be difficult and unpredictable [2]. To increase access to these materials in optically pure form, over the past decade several groups have developed small molecule catalysts for the asymmetric acylation reaction [3,4], In addition, these catalysts... 

Applications of Lipases and Esterases in Pharma 13.4.3.1 LTD4 Antagonist MK-0571... 

The lipase-catalysed access to enantiomerically pure compounds remains a versatile method for the separation of enantiomers. The selected examples shown in this survey demonstrate the broad applicability of lipases in terms of substrate structures and enantioselectivity. More recently, modem molecular biology methods such as rational protein design and especially directed evolution103 will further boost the development of tailor-made lipases for future applications in the synthesis of optically pure compounds. It has been already shown that a virtually non-enantioselective lipase (E=l.l in the resolution of 2-methyldecanoate) could be evolved to become an effective biocatalyst (E>50). Furthermore, variants were identified which showed opposite enantiopreference. 

Haraldsson, G. The application of lipases in organic synthesis in The chemistry of acid derivatives edited by S. Patai, John Wiley Sons Ltd 1992, vol. 2, 1396-1467. 

Shimada, Y. 2001c. Application of lipase reactions to separate and purification of useful materials. INFORM, 12,1168-1174. 

Shimada, Y., Watanabe, Y., and Nagao, T. 2005a. Application of lipases to industrial-scale purification of oil- and fat-related compounds. In C. T. Hou (Ed.), Handbook of Industrial Biocatalysis (Chap. 8). Boca Raton, FL CRC Press, Taylor Francis Group. 

There is considerable worldwide interest in the application of lipases for fat modification and ester synthesis. In systems with low water activity, lipases are able to catalyze ester synthesis as well as interesterification reactions in fats. The lipase reactions under low water activity can be performed in several ways. We consider batch or continuous reactions in melted fats by use of immobilized lipases as the most relevant way for the industry. 

Ghanem A, Aboul-Enein HY. Application of lipases in kinetic... 

Jaeger, K.E. Dijkstra, B.W. Reetz, M.T. Bacterial biocatalysts molecular biology, three-dimensional structures, and biotechnological applications of lipases. Ann. Rev. Microbiol. 1999,53 (1), 315-351. 

In addition to hydrolyzing carboxylic ester bonds, lipases can catalyze a variety of esterification reactions in non-aqueous media. Industrial applications of lipases have focused on their enantioselectivity, regioselectively and substrate... 

An application of lipases in the pharmaceutical industry can he found in the manufacture of Ihuprofen (Houde et al., 2004). Ihuprofen is a racemic mixture, where the (S)-ihuprofen molecules is 160 times more potent that the (R)-ihuprofen one. Resolution of racemic ihuprofen can he achieved hy esterification of (S)-ibuprofen with methanol or hutanol, in organic media using lipase, leading to synthesis of the corresponding (S)-ester. This ester can be separated from (R)-ibuprofen and chemical transformed to (S)-ibuprofen. 

Lipases (triacyl glycerol acyl hydrolases, E.C. 3.1.1.3) are a unique class of hydrolases i113-115 for asymmetric synthesis based on prochiral or racemic substrates. The application of lipases as biocatalysts has been reviewed emphasizing different... 

Of the six main classes of enzymes, hydrolases, oxidoreductases and transferases have been the three most useful in kinetic resolution. Among the hydrolases, lipases are extensively used. The molecular machinery of lipases consists of a catalytic triad of the amino acids serine, histidine, and aspartic (or glutamic) acid. The enzyme first transfers the acyl group of an ester to the hydroxyl group of the serine residue to form the acylated enzyme. The acyl group is subsequently transferred to an external nucleophile with the return of the enzyme to its pre-acylated state to start the process again. A variety of nucleophiles can participate in this process water results in hydrolysis, an amine results in amidation, an alcohol results in esterification or transesterification, and hydrogen peroxide results in the formation of perac-id. Another reason which favored the relatively wide applicability of lipases in enzymatic... 

Hasan F, Shah AA, Hameed A (2006) Industrial applications of lipases. Enzyme Microb Technol... 

Houssam ER, Perrard A, Pierre AC (2004) Application of lipase encapsulated in silica aerogels to a transesterification reaction in hydrophobic and hydrophilic solvents bi-bi ping-pong kinetics. J Mol Catal B Enzym 30(3 ) 137-150... 

Schoevaait R, Wolbers MW, Golubovic M et al. (2004) Preparation, optimization and structures of cross-Unked enzyme aggregates (CLEAs). Biotechnol Bioeng 87 754-762 Schulz T, Plesis J, Schmid RD (2000) Stereoselectivity of Pseudomonas cepacia lipase toward secondtuy alcohols a quantitative model. Protein Sci 9 1053-1062 Secundo F, Cturea, G, Tarabiono C et al. (2006) The lid is a stmctural and functional determinant of lipase activity and selectivity. J Mol Catal B Enzym 39 166-170 Seitz EW (1974) Industrial application of microbial lipases a review. JAOCS 51(2) 12-16 Sharma R, Chisti Y, Baneijee UC (2(X)1) Production, purification, characterization and application of lipases. Botechnol Adv 19 627-662... 

Vulfson EN (1994) Industrial applications of lipases. In Woolley P, Peterson SB (eds). Lipases their structure, biochemistry and applications. Cambridge University Press, Cambridge, pp 271-288... 

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