Resolution of d,l-menthol by interesterification with triacetin using the free and immobilized lipase of Candida cylindracea

Lokotsch, Wolfram; Fritsche, Kirsten; Syldatk, Christoph

doi:10.1007/bf00270778

Cited by 28 publications

(15 citation statements)

References 15 publications

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“…At 30°C, nearly 50% of (−)-menthol was converted to the ester form after 48 h incubation. The reaction rate was comparable to enzymatic resolutions of (±)-menthol obtained previously with lipase from C. cylindracea (1,12).…”

Section: Resultssupporting

confidence: 81%

Stereoselective acylation of Dl‐menthol in organic solvents by an immobilized lipase from Pseudomonas cepacia with vinyl propionate

Akoh

Phillips

1997

J Americ Oil Chem Soc

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An effective lipase-catalyzed stereoselective transesterification of (±)-menthol in organic solvent with vinyl propionate as acylating agent is described. Immobilization by adsorption and the presence of molecular sieves improved the formation of (±)-menthyl propionate by lipase (PS-30) from Pseudomonas cepacia. The reaction time course, mole ratio of substrates, temperature, amount of enzyme, as well as the effect of various organic solvents, were examined for their influence on the enzymatic stereoselective formation of (−)-menthyl propionate. Among the parameters studied, the stereospecificity toward (−)-menthol decreased significantly as temperature increased but the yields of both enantiomers increased. Organic solvents with log P (partition coefficient) values above 3.5 gave higher yield and stereoselectivity than solvents with lower log P values. JAOCS 74, 435-439 (1997).

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Section: Resultssupporting

confidence: 81%

Stereoselective acylation of Dl‐menthol in organic solvents by an immobilized lipase from Pseudomonas cepacia with vinyl propionate

Akoh

Phillips

1997

J Americ Oil Chem Soc

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“…2). As for enantioselectivity, it was verified, using a previously reported CrL-mediated esterification between L-and D-menthol and lauric acid in isooctane (33) as the model reaction, that imprinting resulted in a considerable increase of activity towards the L-isomer (preferred isomer) without appreciable loss of enzyme enantiodiscrimination. Finally, when interface-unrelated, nonlipolytic enzymes such a-chymotrypsin and subtilisin were assayed for an N-acetyl amino acid ester transesterification model reaction, it was verified that they could not be activated under conditions optimal for imprinting of lipases.…”

Section: Resultsmentioning

confidence: 69%

Interfacial activation-based molecular bioimprinting of lipolytic enzymes.

Mingarro

Abad

Braco

1995

Proc. Natl. Acad. Sci. U.S.A.

140

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Interfacial activation-based molecular (bio)-imprinting (IAMI) has been developed to rationally improve the performance of lipolytic enzymes in nonaqueous environments. The strategy combinedly exploits (i) the known dramatic enhancement of the protein conformational rigidity in a water-restricted milieu and (ii) the reported conformational changes associated with the activation of these enzymes at lipid-water interfaces, which basically involves an increased substrate accessibility to the active site and/or an induction of a more competent catalytic machinery. Six model enzymes have been assayed in several model reactions in nonaqueous media. The results, rationalized in light of the present biochemical and structural knowledge, show that the IAMI approach represents a straightforward, versatile method to generate manageable, activated (kinetically trapped) forms of lipolytic enzymes, providing under optimal conditions nonaqueous rate enhancements of up to two orders of magnitude. It is also shown that imprintability of lipolytic enzymes depends not only on the nature of the enzyme but also on the "quality" of the interface used as the template.Nonaqueous enzymology has emerged in the last decade as a promising research field (for reviews, see, for example, refs. 1-3), not only because of a large number of widely recognized advantages (2) but especially as a result of the realization that enzymes placed in nearly anhydrous environments can exhibit exciting features, such as an increased conformational rigidity, which confers on the protein greatly enhanced (thermo)stability (4), or a profoundly altered substrate specificity (5). In particular, one interesting facet of the exploitation of the drastically lowered flexibility of a protein in very low-water media is the so-called ligand-induced enzyme "memory" (or simply ligand memory) (6), presumably based on inducing, upon ligand binding, an enzyme conformational change that (after freeze-drying of the solution) will be preserved in the lyophilized sample when exposed to anhydrous solvents. This strategy, also referred to as molecular (bio)imprinting (7,8), has been extended to nonenzymic proteins and other macromolecules (9, 10) and shares a conceptual analogy with the previously known molecular imprinting of polymers (for a review, see ref. 11). In the case of enzyme (bio)imprinting, only scarce efforts have been reported so far, which have focused on a very few related proteases and made use of competitive inhibitors (amino acid derivatives) as print molecules (6-8). Although these preliminary results seem indeed encouraging in terms of an activity enhancement or even an apparent (stereo)selectivity alteration in the organic milieu, the nature of the presumptive conformational changes induced has not been characterized, and the molecular reasons for the experimental observations are still open to debate (12).Paradoxically, in this context, no effort aimed at assessing the possibility of imprinting lipolytic enzymes has been reThe publication costs of th...

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“…Previously it has been shown that when using a fixed concentration of dodecanol or tetradecanol as acyl acceptor and crude C. rugosa lipase, the enantioselectivity was markedly decreased with a decreased water activity (Hligberg et at., 1993). However, it is known that the rates of esterification is less dependent on water content when using immobilised compared with crude C. rugosa iipase (Lokotsch et al, 1989). The commercial lipase from C. rugosa contains isoenzymes with slightly different properties, as has been pointed out by several authors (e.g.…”

Section: Discussionmentioning

confidence: 92%

Alcohols as enantioselective inhibitors in a lipase catalysed esterification of a chiral acyl donor

et al. 1995

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Increased reaction rates and increased enantioselectivities were observed with decreased concentrations of n-alkanols when resolving 2-methyldecanoic acid by esterification catalysed by imrnobilised lipase from Candida rugosu at controlled water activities in cyclohexane. The enantioselectivity was found to be independent of the water activity in the reaction medium at the n-heptanol concentrations investigated. However, when ndecanol was used as the acyl acceptor, not only the alcohol concentration but also the water activity in the reaction medium, influenced the enantioselectivity. The results obtained showed that the low enantioselectivity seen at a high alcohol concentration could be explained by the alcohol influencing the apparent V,S,, and V&x differently.

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Resolution of d,l-menthol by interesterification with triacetin using the free and immobilized lipase of Candida cylindracea

Cited by 28 publications

References 15 publications

Stereoselective acylation of Dl‐menthol in organic solvents by an immobilized lipase from Pseudomonas cepacia with vinyl propionate

Stereoselective acylation of Dl‐menthol in organic solvents by an immobilized lipase from Pseudomonas cepacia with vinyl propionate

Interfacial activation-based molecular bioimprinting of lipolytic enzymes.

Alcohols as enantioselective inhibitors in a lipase catalysed esterification of a chiral acyl donor

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