Mucor miehei lipase

The ability of lipases to synthesize the amide bond has been shown (26). Mucor miehei lipase (NOVO tipozyme) has been used in the reaction of laurylamine and oleic acid at 60°C. Water was shown to inhibit the synthesis of this Ai-lauryloleamide (27). 

Conduritols and inositols are cyclic polyalcohols with significant biological activity. The presence of four stereogenic centers in the stmcture of conduritols allows the existence of 10 stereoisomers. Enzymatic methods have been reported for the resolution of racemic mixtures or the desymmetrization of meso-conduritols. For example, Mucor miehei lipase (MML) showed enantiomeric discrimination between all-(R) and all-(S) stereoisomers ofconduritol E tetraacetate (Figure 6.52). Alcoholysis resulted in the removal of the four acetyl groups ofthe all-(R) enantiomer whereas the all-(S) enantiomer was recovered [141]. 

Immobilized Mucor miehei lipase (lipase MM) induced the polycondensation of adipic acid and 1,4-butanediol in ether solvents [26]. A horizontal two-chamber reactor was employed to facilitate the use of the molecular sieves. A low disper-sity polyester with DP = 20 was obtained by two-stage polymerization. 

Mucor miehei lipase (ITGL) [59] Seri 44 Leul45 Ser82 Ser82 OG ... 

The stability of the ester surfactants against enzymatic hydrolysis by two different microbial Upases, Mucor miehei lipase (MML) and Candida antarc-tica lipase B (CALB) added separately to the surfactant solutions, was also investigated, see Fig. 5 [19]. It is obvious that hydrolysis of the unsubstituted surfactant is much faster with both CALB and MML than that of the substituted surfactants, i.e., increased steric hindrance near the ester bond leads to decreased hydrolysis rate. Since the specificity of the enzyme against its substrate is determined by the structure of the active site, it can be concluded, as expected, that the straight chain surfactant most easily fits into the active site of both enzymes. 

The activity of three ester spHtting enzymes, Candida antarctica lipase B (CALB), Mucor miehei lipase (MML) and esterase, towards the carbonate surfactant was studied. While CALB and esterase were found to catalyze the hydrolysis of the carbonate bond, MML showed no activity. 

Lipases are serine hydrolases that catalyse the hydrolysis of lipids to fatty acids and glycerol [2]. In contrast to esterases, they work at the lipid-water interface and show only little activity in aqueous solutions. Studies of the X-ray structures of human lipase [3,4] and Mucor miehei lipase [5,6] revealed a change in conformation at the lipid-water interface, which explains the increase of activity. 

Lipolysed milk fat was one of the first flavours produced with the help of enzymes. The original process was based on the controlled lipase-catalysed hydrolysis of cream [18]. For instance, Mucor miehei lipase possesses a high selectivity towards flavour-active short-chain fatty acids. Additionally, lipases that prefer long-chain fatty acids or lipases without particular preferences can be found. The free fatty acids produced can be isolated by steam distillation and further purified. Thus, it is possible to obtain pure short-chain fatty acids like butanoic, hexanoic, octanoic and decanoic acid. 

Methylbutanoates and methylbutyl esters are essential flavour compounds in fruit flavours they can be produced biotechnologically as mentioned before. Chowdary et al. [33] have described the production of a fruit-like flavour isoamyl isovalerate by direct esterification of isoamyl alcohol and isovaleric acid in hexane with the help of Mucor miehei lipase immobilised on a weak anion-exchange resin. 

TIL Thermomyces lanuginosus lipase, RdL Rhizopus delemar lipase, RnL Rhizopus niveus lipase, MmE Mucor miehei esterase, PsL Pseudomonas sp. lipase, MmL Mucor miehei lipase, RoL Rhizopus orvzae lipase, CaLA Candida antarctica lipase A, CaLB Candida antarctica lipase B, PLE Pig liver esterase, EP Enteropeptidase, PKA Porcine kidney acylase, CE Cholesterol esterase Figure 8.1 (S)-Selective enzyme hits from hydrolase screening. ... 

Activity maxima at certain aw values have also been found with many other enzymes, such as optima at aw = 0.55 for Mucor miehei lipase-catalyzed reaction in several solvents of different polarity from hexane to 3-pentanone (Valivety, 1992a). In comparing five different lipases, considerable variations not just of the optima of aw but also the dependence of activity on aw itself were found (Valivety, 1992b). Moreover, in polar solvents, correlations of activity with aw often cannot be found at all, probably owing to solvent effects beyond those controlling hydration of the enzyme (Bell, 1997). 

A part from vinyl acetate, vinyl benzoate was used as acylating agent in the Mucor miehei lipase (MML) and Candida antarctica lipase (CAL)-catalysed benzoylation of 1,2-diols in organic solvents 87.87 The reaction proceeded with high regioselectivity and moderate enantioselectivity. 

Ester Synthesis Catalyzed by Mucor miehei Lipase Immobilized on Magnetic Polysiloxane-Polyvinyl Alcohol Particles... 

Here, we report the application of this procedure for immobilizing Mucor miehei lipase. A catalytic test was aimed at producing esters by direct esterification reactions with a large range of carboxylic acids (from C4 to C16), and a diversity of alcohols (from C4 to C8). Several reaction model systems are analyzed in order to illustrate the kind of products that can be made by using an experimental preparation of lipase immobilized on POS-PVA particles. 

Mucor miehei lipase (4.79 0.21 U/mg of protein) was kindly donated by Novozymes (Araucaria, PR, Brazil). TEOS was from Aldrich (Milwau-... 

Lypozyme IM-20 (Mucor miehei lipase immobilized on a weak anion-exchange resin) was kindly supplied by Novo Nordisk (Bagsvaerd, Denmark). The gas chromatography (GC) standards (mono-, di-, and trilaurin) were obtained from Sigma (St. Louis, MO). Analytical-grade glycerol, lauric acid (99.9%), n-hexane, ethyl acetate, acetone, and ethanol were purchased from Merck (Darmstadt, Germany). 

The three dimensional structures of human pancreatic Lipase and Rhizo-mucor miehei lipase have recently been elucidated 1141-1431. Among the lipases purified foam different sources—mammals, bacteria, fungi, and plants-—the fungal lipases from Rhizopuj species exhibit a remarkably broad pH zone of stability and activity, extending from pH 3 to 9. 

For industrial applications, thermostable lipases are desirable in order to work in melted fat. Thermostable, positional specific lipases are well known. One example is Mucor miehei lipase which we have developed into an immobilized commercial product (Lipozyme)... 

This fatty acid specificity may lead to the assumption that the activity in acidolysis of polyunsaturated fatty acids would be negligible. We have tested the incorporation of polyunsaturated fatty acids isolated from menhaden oil into trilaurin, and found that both immobilized Lipase A and the immobilized crude enzyme are quite active, and more active than the immobilized Mucor miehei lipase (Lipozyme). 

Lipases liberated from the testa and the cross cells promote rapid hydrolysis of the oil, and therefore, it should be extracted within hours of milling. Attempts have been made to upgrade oil with 30% free acid by reaction with glycerol and the enzyme Lipozyme Mucor miehei lipase) followed by neutralization. The major acids in rice bran oil are palmitic (12-18%, typically 16%) oleic (40-50%, typically 42%), and linoleic acid (29 2%, typically 37%). The oil contains phospholipids ( 5%), a wax that may be removed and finds industrial use, and unsaponifiable matter including sterols, 4-methylsterols, triterpene alcohols, tocopherols, and squalene among others. 

Candida antractica lipase B- and immobilised Mucor miehei lipase- catalysed alcoholysis and C-rugosa lipase- catalysed hydrolysis have been successfully used for the highly effective synthesis of optically active trifluoromethylated 1-and 2-hydroxyalkane-phosphonates (268) and (269) from their racemic O-acylated precursors (270) and (271) (Scheme 68). ... 

Enzymatic alcoholysis of 3-chloro-2-chloroacetoxy, 3-azido-2-chloroacetoxy and l-chloro-2-chloroacetoxypropyl phosphonates (285), (286) and (287) catalysed by immobilized mucor miehei lipase (IM) and Candida antarectica lipase B was a particularly effective method for the formation of the corresponding highly enriched enantiomerically chloroacetoxyphosphonates (288), (289) and (290). Kinetic resolution by specially selected reaction sequences led to phosphocarnitine (291), phosphogabob (292) and phosphomycin (293) respectively (Scheme 73). ... 

The use of lipase-catalyzed ester hydrolyses or transesterification reactions has led, interestingly, to an efficient method for synthesizing the N-benzoyl-(21 ,3S)-3-phenyl isoserine moiety, the C-13 side chain of taxol. The Mucor miehei lipase proved to be uniquely suited for the stereospecific transesterification of racemic methyl fra s-/l-phenyl glycidate. Further improvement of this reaction led to the choice of an isobutanol-hexane mixture (1 1 vol/vol) as the... 

Table 11.1-11. Lipase-catalyzed enantiotopos-differentiating hydrolysis of prochiral cyclic diol dialkanoates in aqueous solution (CCL Candida cylindracea lipase, PFL Pseudomonas jiuorescens lipase, MML Mucor miehei lipase, CVL Chromobacterium viscosum lipase, PPL pig pancreas lipase, MJL Mucor javanicus lipase, RSL Rhizopus sp. lipase, PCL Pseudomonas cepacia lipase, CCL, Ceotricum candidum lipase, ANL Aspergillus niger lipase, FSPC Fusarium solani pisi cutinase, CRL Candida rugosa lipase, CAL-B Candida antarctica B lipase, LIP Pseudomonas sp. lipase-Toyobo, RDL Rhizopus delemar lipase, MSL Mucor sp. lipase, CAL Candida antarctica lipase, not specified).

MML Mucor miehei lipase, CAL-B Candida antarctica B lipase, LIP Pseudomonas sp. lipase -Toyobo, HSL Humicola sp. lipase). 

PCL Pseudomonas cepacia lipase, CCL Candida cylindracea lipase, MML Mucor miehei lipase,... 

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