Lipases cylindracea

Candida cylindracea, phosphate buffer pH 7, Bu20. The 6-0-acetyl of Q -methyl peracetylglucose was selectively removed. Porcine pancreatic lipase will also hydrolyze acetyl groups from carbohydrates. These lipases are not specific for acetate since they hydrolyze other esters as well. In general selectivity is dependent on the ester and the substrate. ... 

Candida cylindracea lipase, BuOH, hexane, 3 h, 25°, 40-100% yield. 

Williams and coworkers have reported a DKR of ot-bromo [56a] and a-chloro esters [56b]. In the latter case, the KR is catalyzed by commerdally available cross-linked enzyme crystals derived from Candida cylindracea lipase. The racemization takes place through halide 5 2 displacement. The DKR is possible because the racemization of the substrate is faster than that of the produd (carboxylate). For the ester, the empty ii (C=0) orbital is able to stabilize the Sn2 transition state by accepting... 

The resolution of racemic ethyl 2-chloropropionate with aliphatic and aromatic amines using Candida cylindracea lipase (CCL) [28] was one of the first examples that showed the possibilities of this kind of processes for the resolution of racemic esters or the preparation of chiral amides in benign conditions. Normally, in these enzymatic aminolysis reactions the enzyme is selective toward the (S)-isomer of the ester. Recently, the resolution ofthis ester has been carried out through a dynamic kinetic resolution (DKR) via aminolysis catalyzed by encapsulated CCL in the presence of triphenylphosphonium chloride immobilized on Merrifield resin (Scheme 7.13). This process has allowed the preparation of (S)-amides with high isolated yields and good enantiomeric excesses [29]. 

Various cyclic esters have been subjected to hpase-catalyzed ring-opening polymerization. Lipase catalyzed the ring-opening polymerization of 4- to 17-membered non-substituted lactones.In 1993, it was first demonstrated that medium-size lactones, 8-valerolactone (8-VL, six-membered) and e-caprolactone (e-CL, seven-membered), were polymerized by lipases derived from Candida cylindracea, Burkholderia cepacia (lipase BC), Pseudomonas fluorescens (lipase PF), and porcine pancreas (PPL). °... 

Stirred-tank reactor Alcoholysis of 1-phenyl ethyl butyrate and 1-heptanol Lipase from Candida cylindracea 120... 

A continuous stirred tank reactor has been reported for the hydrolysis of the triglycerides existing in vegetable oil in the presence of the aqueous phase and for synthesis reactions (Table 5). A microfilter can be used to prevent the immobilized enzyme from leaving the reactor. Kawano et al. [115] investigated the hydrolysis of olive oil in octane with Candida cylindracea lipase in aqueous solution in a Vibro Mixer reactor containing vibration plates connected to the crankshaft of a motor and oscillated with fixed rates. 

Enantiomerically pure japonilure [(4JR,5Z)-5-tetradecen-4-olide, 26] is commercially important to attract the Japanese beetle (Popillia japonica), because only pure (4.R,5Z)-26 is bioactive, while ( )-26 is totally inactive. Synthesis of (4 ,5Z)-26 via enzymatic resolution of racemic intermediates was first reported by Sugai [63], and then further studied by Fukusaki [64] to establish the process as summarized in Scheme 39. Lipase PS (Amano) from Pseudomonas sp. and lipase OF (Meito) from Candida cylindracea were shown to be the enzymes of choice. 

Enzyme activity varies greatly depending on solvent choice, as illustrated by Zaks and Klibanov for the transesterification of tributyrin and heptanol by three different lipases. Using these data, Laane et found that enzyme activity correlates closely with solvent hydrophobicity (log P) for the lipases from Mucor sp. (MML) and Candida cylindracea... 

CCL lipase from Candida cylindracea (now known as lipase from... 

To test the selectivity of the self-screening process, six other enzymes belonging to the hydrolase family were tested under the same set of conditions as in DCL-A. These enzymes were butyrylcholinesterase, horse fiver esterase (HLE, EC 3.1.1.1), Candida cylindracea lipase (CCL, EC 3.1.1.3), (3-galactosidase ((3-Gal, EC 3.2.1.23), trypsin (EC 3.4.21.4), and... 

Hydrolysis of Polyester by Lipase. Aliphatic polyester, PEA and PCL were hydrolyzed by lipases from Achromobacter sp., C. cylindracea,... 

Rua, M L., Diaz-Maurino, T. Fernandez, V.M., Otero, C. and Ballesteros, A. (1993) Purification and partial characterization of two distinct lipases from Candida cylindracea. Biochim. Biophys. Acta., 1156, 181-189. 

Kinetic optical resolution of racemic alcohols and carboxylic acids by enzymatic acyl transfer reactions has received enormous attention in recent years56. The enzymes generally employed are commercially available lipases and esterases, preferentially porcine liver esterase (PLE) or porcine pancreatic lipase (PPL). Lipases from microorganisms, such as Candida cylindracea, Rhizopus arrhizus or Chromobacterium viscosum, are also fairly common. A list of suitable enzymes is found in reference 57. Standard procedures are described in reference 58. Some examples of the resolution of racemic alcohols are given39. 

Lipases (triacyl glycerol acyl hydrolases, E.C 3.1.1.3) are a unique class of hydrolases for asymmetric synthesis86,87,S9,90e, They are available from fungi, bacteria and mammalians. The lipases most commonly used so far are the commercially supplied pig pancreas lipase (PPL)136, Pseudomonas cepacia lipase (PCL)89,137 and Candida cylindracea lipase (CCL). In most cases only the crude lipases, consisting of a mixture of proteins which may even be other hydrolases, are successfully applied1373. 

It has been demonstrated that the activity of the lipase Candida cylindracea) catalyzed transesterification reaction between methylmethacrylate and 2-ethylhexanol in... 

It is known that enantioselectivity of enzymes depends on many different parameters such as temperature, substrate structure, reaction medium, and presence of water. Enantiopreference of enzymes can be greatly affected, even reversed, by changing the reaction solvent. Such an example was reported by Ueji et al. in 1992 for Candida cylindracea lipase-catalyzed esterification of ( )-2-phenoxy propionic acid with 1-butanol [29]. 

If the bonded water is extracted by dry CO2 the enzyme is denaturated and loses its activity. Therefore a certain amount of water is necessary in the supercritical fluid because acting with water-saturated CO2 again causes an inhibition of the enzyme and consequent loss of activity. The optimal water concentration has to be determined for each enzyme separately. Table 9.2-1 shows the residual activity of lipase from Candida cylindracea, esterase from Mucor mihei, and esterase from Porcine liver after a incubation time of 22 hours in supercritical CO2 at 40°C. It is obvious that higher water concentrations cause a strong reduction in the residual activity compared to the activity of the untreated enzyme, which was set as 100 %. Further, the system-pressure has an influence because at higher pressures the activity-loss is lower with a larger amount of water in the system [7,8],... 

Residual activity at different CO2 humidity at 40°C, 22 hours incubation time and 170 mL total volume of the system (I, lipase from Candida cylindracea II, esterase from Mucor mihev, III, esterase from Porcine liver) ... 

Residual activity of different enzymes after 1 hour treatment in supercritical CO2 at 150 bar (I, lipase from Candida cylindracea If, lipase Amano AY III, lipase from Pseudomonas sp. IV, esterase EP10 from Burkholderia gladioli) ... 

Candida antarctica (enantioselective) Candida cylindracea lipase (enantioselective)... 

However, it seems that empirical trials are still necessary in order to achieve a successful synthesis several enzymes from different natural sources should be tested, and even enzymes having different specificities. For laboratory-scale preparations, the cost of such enzymes as the lipases from porcine pancreas (PPL), Candida cylindracea (CCL), and Chromobacterium viscosum (CVL), and Protease N (Amano) is negligible. Subtilisin, a protease, is much more expensive. 

Resolution of racemic alcohols by acylation (Table 6) is as popular as that by hydrolysis. Because of the simplicity of reactions in nonaqueous media, acylation routes are often preferred. As in hydrolytic reactions, selectivity of esterification may depend on the structure of the acylating agent. Whereas Candida cylindracea lipase-catalyzed acylation of racemic-Ot-methylbenzyl alcohol [98-85-1] (59) with butyric acid has an enantiomeric value E of 20, acylation with dodecanoic acid increases the E value to 46 (16). Not only acids but also anhydrides are used as acylating agents. Pseudomonasjl. lipase (PFL), for example, catalyzed acylation of OC-phenethanol [98-85-1] (59) with acetic anhydride in 42% yield and 92% selectivity (74). 

A number of steroids have been regioselectively acylated in a similar manner (99,104). Chromobacterium viscosum lipase esterifies 5a-androstane-3p,17p-diol [571-20-0] (75) with 2,2,2-trifluoroethyl butyrate in acetone with high selectivity. The lipase acylates exclusively the hydroxy group in the 3-position giving the 3p-(monobutyryl ester) of (75) in 83% yield. In contrast, bacillus subtilis protease (subtilisin) displays a marked preference for the C-17 hydroxyl. Candida cylindracea lipase (CCL) suspended in anhydrous benzene regioselectively acylates the 3a-hydroxyl group of several bile acid derivatives (104). 

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