Candida antartica lipase B

Chemo-enzymatic epoxidation of unsaturated fatty acids with aqueous H2O2 has been conducted with considerable success and here we have a remarkable situation that undesirable ring opening of the epoxide does not occur. Excellent activity and stability has been realized with Novozym 435, a Candida antartica lipase B immobilized on polyacryl. This enzyme is readily separable, can be used several times without loss of activity, and has a turnover of more than 2,00,000 moles of products per mole of catalyst (Bierman et al., 2000). 

De Diego, T., Lozano, R, Gmouh, S., Vaultier, M., Iborra, J.L., Understanding structure-stability relationships of Candida antartica lipase B in ionic liquids, Biomacromol., 6,1457-1464, 2005. 

To achieve better results a series of lipases was screened using the Chirazyme screening kit and analysis by gas chromatography with a chiral stationary phase. Candida antartica Lipase B, available as Novozyme 435, was chosen for further development with the acyl transfer agent vinyl propionate. 

Candida antartica lipase B Na2C03 (1 mmol) AcOCMe=CH2 (1.5 mmol) toluene, 25 °C... 

Kumar, A., and Gross, R.A. (2000) Candida antartica lipase B catalyzed polycaprolactone synthesis effects of organic media and temperature. Biomacromolecules, 1, 133-138. 

The synthesis of DPP-IV inhibitor Saxagliptin 5 also required (55)-5-amino-carbonyl-4,5-dihydro-lH-pyrrole-l-carboxylic acid, l-(l,l-dimethylethyl)ester 10 (Figure 16.3C). Direct chemical ammonolyses were hindered by the requirement for aggressive reaction conditions, which resulted in unacceptable levels of amide race-mization and side-product formation, while milder two-step hydrolysis-condensation protocols using coupling agents such as 4-(4,6-dimethoxy-l,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) [41] were compromised by reduced overall yields. To address this issue, a biocatalytic procedure was developed based on the Candida antartica lipase B (CALB)-mediated ammonolysis of (55)-4,5-dihydro-lH-pyrrole-l,5-dicarboxylic acid, l-(l,l-dimethylethyl)-5-ethyl ester 9 with ammonium carbamate to furnish 10 without racemization and with low levels of side-product formation. 

Vaidya, A. Xie, W. Gao, W. Bohling, J.C. Miller, M.E. Gross, R. A. Enzyme immobilization without a support Candida antartica lipase B (CALB) Self-crosslinked aggregates ACS Polymer Preprints, 2006, 47(2), 236. 

Table 1. Candida antartica Lipase B (CALB) immobilization on MM A resins of differing particle size enzyme loading, fraction of active lipase,...

Zhou, Y, Oostenbrink, C., van Maanen, E.M.T., Hagen, W.R., de Leeuw, S.W., Jongejan, J.A. Molecular modeling of the enantioselectivity of Candida antartica lipase b— free energy calculation, J. Comp. Chem, in press. 

Biocatalysts can also be used in the complete absence of water. Candida antartica lipase B (CaLB), used either as the free enzyme or in an immobilized form, catalyzes transesterification, ammonolysis andperhydrolysis. For example, octanoic acid was quantitatively transformed to amide 107 in 4 days (Scheme 46) - a significant rate... 

Lozano P, Pdrez-Mann A B, De Diego T, Gomez D, Paolucci-Jeanjean D, Belleville M P, Rios G M, Iborra J L (2002), Active membranes coated with Candida antartica Lipase B preparation and application for continuous butyl butirate synthesis in organic media , J. Membrane Sci., 201,55-64. 

Chiral phosphonous acid diester induces the kinetic resolution of racemic a-substituted y-unsaturated carboxylic acids through asymmetric protolac-tonization (Scheme 53) (130L2838). Dinamic kinetic resolution with Candida antartica lipase B and the ruthenium catalyst [RuCl(CO)2(T -C5Ph5)] of several homoallylic alcohols is applied in the key step to the synthesis of enantiomericaUy pure 5,6-dihydro-2ff-pyran-2-ones ( [13CEJ13859]). 

A popular and effective lipase is Novozym 435, an immobilized Candida antartica Lipase B (CALB), available commercially fi om Novozymes A/S. This enzyme was invoked in at least 11 of the articles in this book (16,20,25-33). 

The modification of polysaccharides using enzymes has been studied to attain more uniformly substituted products under mild reaction conditions. Hydroxyethylcellulose (HEC) particles were suspended in dimethylacetamide and acylated with vinyl stearate using Candida antartica Lipase B (CAL-B) as the catalyst. After 48 hrs, a product with degree of substitution (D.S.) of 0.1 was formed(8). HEC in film or powder form was modified using lipase-catalysis and e-caprolactone (CL) to form low D.S. HEC-g-PCL copolymers(9). Problems that limit the utility of these reactions include the use of polar aprotic solvents that strip the critical water from enzymes lowering their activities(lO) and the use of heterogeneous reaction conditions that restrict the modification of large particles and films to a small fraction of the substrate that resides at die surface. 

For example Kumar, A., and Gross, R. A., 2000, Candida antarctica Lipase B-Catalyzed Transesterification New Synthetic Routes to Copolyesters. J. Am. Chem. Soc. 122 11767-11770 Kumar, A., and Gross, R. A., 2000, Candida antartica lipase B catalyzed polycaprolactone synthesis effects of organic media and temperature. Biomacromolecules 1 133-138 Kobayashi, S, Uyama, H., Namekawa, S., and Hayakawa, H., 1998, Enzymic Ring-Opening Polymerization and Copolymerization of 8-Octanolide by Lipase Catalyst. Macromolecules 31 5655. 

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