Solvent effect on lipase enantioselectivity. Evidence for the presence of two thermodynamic states

Pl, Overbeeke; Ja, Jongejan; Heijnen, J. J.

doi:10.1002/1097-0290(20001105)70:3<278::aid-bit5>3.0.co;2-i

Cited by 34 publications

(14 citation statements)

References 57 publications

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“…As expected for primary alcohols, 6 the enantioselectivity obtained in the transesterification with lipase PS (Burkholderia cepacia) in ether was low (E 7 = 17 at best) at room temperature despite considerable efforts such as screening of lipases, solvents, additives, and acylating agents. [8][9][10][11][12] As the final choice, we examined the reaction at low temperatures, and found that lowering the temperature to À40°C (Fig. 2) increased the E value of 17 (at 30°C) to a practically acceptable level of 99, and the plot of the temperature effect between ln E and 1/T showed a linear correlation, obeying EyringÕs equation (1).…”

Section: Discovery and Applicability Of The 'Low-temperature Method' mentioning

confidence: 99%

‘Low-temperature method’ for a dramatic improvement in enantioselectivity in lipase-catalyzed reactions

Sakai

2004

Tetrahedron: Asymmetry

102

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Section: Discovery and Applicability Of The 'Low-temperature Method' mentioning

confidence: 99%

‘Low-temperature method’ for a dramatic improvement in enantioselectivity in lipase-catalyzed reactions

Sakai

2004

Tetrahedron: Asymmetry

102

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“…The proposed implication of temperature on enantioselectivity was supported by a number of studies where the enantiopreference of enzymes showed better results at low temperatures , . However, the report stated that enantioselectivity is normally reduced at lower temperatures .…”

Section: Resultsmentioning

confidence: 96%

“…While Δ ( R − S ) ΔG ‡ is defined as the difference between enthalpy, Δ ( R − S ) ΔH ‡ and entropy, Δ ( R − S ) ΔS ‡ of activation. This relationship can be further described by the Arrhenius‐type model of R ln E against the inverse of reaction temperature as presented by:, …”

Section: Resultsmentioning

confidence: 99%

“…In terms of differential activation entropy (Δ ( R − S ) ΔS ‡ ), no significant change was observed between the two media, and almost the same values of Δ ( R − S ) ΔS ‡ (0.25 kJ mol −1 K −1 ) were obtained, indicating that there was no enthalpy–entropy compensation effect occurring upon addition of 2% (v/v) DMSO. Overbeeke and co‐workers reported that the enthalpy–entropy compensation effect was caused by changes in activation enthalpy difference and activation entropy difference during the reaction . This effect might occur if higher concentrations of DMSO were introduced into the system.…”

Section: Resultsmentioning

confidence: 99%

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Effect of co‐solvent addition on the reaction kinetics of the lipase‐catalyzed resolution of ibuprofen ester

Gonawan¹,

Yon²,

Kamaruddin³

et al. 2012

J of Chemical Tech & Biotech

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BACKGROUND: The addition of co‐solvent is not limited to enhancing the catalytic rate, it could also assist in situ racemization in the dynamic kinetic resolution of racemic compounds by increasing the reactivity of the base catalyst employed. In the current work, reaction media with the presence of DMSO were investigated in Candida rugosa lipase (EC 3.1.1.3)‐catalyzed hydrolysis of ibuprofen ester that focuses on the thermodynamic effect, reaction stability and implication for the kinetic parameters. RESULTS: The introduction of 2% DMSO increased the reaction rate, conversion, and enantioselectivity of the Candida rugosa lipase‐mediated resolution. However, the performance of the particular enzymatic reaction was reduced when a higher DMSO concentration was added. At lower reaction temperatures, the medium with 2% DMSO exhibited an increase in enantioselectivity, which was attributed to a higher activation energy difference between the fast‐ and slow‐reacting enantiomers compared with the water‐isooctane medium. Additionally, the presence of DMSO had a significant effect on the kinetic parameters, shown by a lower value of Michaelis constant compared with that of a normal reaction without DMSO, which resulted in a fast reaction rate. Finally, inhibition due to the uncompetitive substrate inhibitor was reduced, while the non‐competitive product inhibitor consequently increased. CONCLUSION: This work has demonstrated that only 2% of DMSO can be tolerated by the free Candida rugosa lipase in the resolution of ibuprofen ester. However, it is still able to give significant positive effects on the hydrolysis rate, kinetic parameters and enantioselectivity as well as reaction stability. © 2012 Society of Chemical Industry

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“…In recent years, lipases have been used for the chiral resolution of (R,S)-ibuprofen through mainly direct enantioselective esterification in organic media [11,13,24,29] or enantioselective hydrolysis of its chemically synthesized racemic ester [18,23,25,28]. Microbial lipases have a great potential for commercial applications due to their stability, enantioselectivity and broad substrate specificity [15].…”

Section: Introductionmentioning

confidence: 99%

Optimization of enantioselective resolution of racemic ibuprofen by native lipase from Aspergillus niger

Carvalho¹,

Contesini²,

Bizaco³

et al. 2006

J IND MICROBIOL BIOTECHNOL

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Resolution of (R,S)-ibuprofen (2-(4-isobutylphenyl)propionic acid) enantiomers by esterification reaction with 1-propanol in different organic solvents was studied using native Aspergillus niger lipase. The main variables controlling the process (enzyme concentration and 1-propanol:ibuprofen molar ratio) have been optimized using response surface methodology based on a five-level, two-variable central composite rotatable design, in which the selected objective function was enantioselectivity. This enzyme preparation showed preferentially catalyzes the esterification of R(-)-ibuprofen, and under optimum conditions (7% w/v of enzyme and molar ratio of 2.41:1) the enantiomeric excess of active S(+)-ibuprofen and total conversion values were 79.1 and 48.0%, respectively, and the E-value was 32, after 168 h of reaction in isooctane.

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Solvent effect on lipase enantioselectivity. Evidence for the presence of two thermodynamic states

Cited by 34 publications

References 57 publications

‘Low-temperature method’ for a dramatic improvement in enantioselectivity in lipase-catalyzed reactions

‘Low-temperature method’ for a dramatic improvement in enantioselectivity in lipase-catalyzed reactions

Effect of co‐solvent addition on the reaction kinetics of the lipase‐catalyzed resolution of ibuprofen ester

Optimization of enantioselective resolution of racemic ibuprofen by native lipase from Aspergillus niger

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