Properties of epoxide hydrolase from Aspergillus niger for the hydrolytic kinetic resolution of epoxides in pure organic media

Karboune, Salwa; Archelas, A.; Baratti, J.

doi:10.1016/j.enzmictec.2005.11.002

Cited by 31 publications

(14 citation statements)

References 42 publications

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“…Ionic liquids as cosolvents help to dissolve hydrophobic substrates and suppress spontaneous hydrolysis, but without inactivating the epoxide hydrolases [37,38]. Traditional organic solvents can reduce the activity of epoxide hydrolases [35,36] :10 vol% ethanol in buffer reduced the activity of epoxide hydrolase from Rhodococcus sp. NCIMB 11216 in half and 10 vol% DMF in buffer reduced the activity by one third [34].…”

Section: Mêçíé~ëéë=~åç=bëíéê~ëéë=mentioning

confidence: 99%

Toward advanced ionic liquids. Polar, enzyme-friendly solvents for biocatalysis

Gorke

Srienc

Kazlauskas

2010

Biotechnol Bioproc E

252

159

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Ionic liquids, also called molten salts, are mixtures of cations and anions that melt below 100 o C. Typical ionic liquids are dialkylimidazolium cations with weakly coordinating anions such as (MeOSO 3 ) or (PF 6 ). Advanced ionic liquids such as choline citrate have biodegradable, less expensive, and less toxic anions and cations. Deep eutectic solvents are also included in the advanced ionic liquids. Deep eutectic solvents are mixtures of salts such as choline chloride and uncharged hydrogen bond donors such as urea, oxalic acid, or glycerol. For example, a mixture of choline chloride and urea in 1:2 molar ratio liquefies to form a deep eutectic solvent. Their properties are similar to those of ionic liquids. Water-miscible ionic liquids as cosolvents with water enhance the solubility of substrates or products. Although traditional water-miscible organic solvents also enhance solubility, they often inactivate enzymes, while ionic liquids do not. The enhanced solubility of substrates can increase the rate of reaction and often increases the regioor enantioselectivity. Ionic liquids can also be solvents for non-aqueous reactions. In these cases, they are especially suited to dissolve polar substrates. Polar organic solvent alternatives inactivate enzymes, but ionic liquids do not even when they have similar polarities. Besides their solubility properties, ionic liquids and deep eutectic solvents may be greener than organic solvents because ionic liquids are nonvolatile, and can be made from nontoxic components. This review covers selected examples of enzyme catalyzed reaction in ionic liquids that demonstrate their advantages and unique properties, and point out opportunities for new applications. Most examples involve hydrolases, but oxidoreductases and even whole cell reactions have been reported in ionic liquids. © KSBB hÉóïçêÇëW=áçåáÅ=äáèìáÇëI=ÇÉÉé=ÉìíÉÅíáÅ=ëçäîÉåíëI=ÜóÇêçä~ëÉëI=çñáÇçêÉÇìÅí~ëÉëI=éçäóãÉêáò~íáçå= = = = = IONIC LIQUIDS AND DEEP EUTECTIC SOLVENTSIonic liquids, also called molten salts, are mixtures of cations and anions that melt below 100 o C. The low melting point stems from a mismatch in the size of the anion and cation that prevents crystallization. Changing the structures of the anions or cations can tune the polarities and other properties. Even though they are salts, their polarities are only moderate, similar to ethanol. Ionic liquids have negligible vapor pressure. Ionic liquids are viscous, typically 0.1 Pas or more, which is similar to glycerol or honey.The first ionic liquid -ethylammonium nitrate (mp 12 o C) -was reported in 1914 [1], but attracted limited use. The first generation of widely studied ionic liquids used the dialkylimmidazolium and related cations reported in 1982 [2], Fig. 1. Varying the cation structure varied the properties of the ionic liquid. The anions were chloroaluminate or other metal halide anions, which react with water and thus are not suited for biotransformations. The second generation of ionic liquids, discovered a decade later [3], replaced the water r...

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Section: Mêçíé~ëéë=~åç=bëíéê~ëéë=mentioning

confidence: 99%

Toward advanced ionic liquids. Polar, enzyme-friendly solvents for biocatalysis

Gorke

Srienc

Kazlauskas

2010

Biotechnol Bioproc E

252

159

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“…The kinetic resolution of p-chlorostyrene oxide 4 in heptane proceeded with a similar level of enantioselectivity as in an aqueous media but with a decreased catalytic efficiency of the epoxide hydrolase. 23 Li et al have kinetically resolved the styrene oxide 1 and its chloro derivatives 4-6 using the epoxide hydrolase from Sphingomonas sp. HXN-200 24,25 in the biphasic system containing n-hexane as an organic phase.…”

Section: Kinetic Resolutionmentioning

confidence: 99%

Recent developments in the asymmetric hydrolytic ring opening of epoxides catalysed by microbial epoxide hydrolase

Bala

Chimni

2010

Tetrahedron: Asymmetry

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“…However, organic solvents decreased the activity and stability of EHs in a twoliquid-phase system due to molecular toxicity and interfacial toxicity (Baldascini and Janssen 2005). The toxicity of organic solvents decreased the catalytic efficiency mainly due to an increase in the K m value (Karboune et al 2006). The diol product inhibition can limit the application of EHs to kinetic resolution at high epoxide substrate concentration.…”

Section: Introductionmentioning

confidence: 98%

Enantioselective resolution of racemic styrene oxide at high concentration using recombinant Pichia pastoris expressing epoxide hydrolase of Rhodotorula glutinis in the presence of surfactant and glycerol

2008

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The reaction medium was optimized to accomplish epoxide hydrolase-catalyzed, batch enantioselective hydrolysis of racemic styrene oxide at high initial substrate concentrations. The recombinant Pichia pastoris containing the epoxide hydrolase gene of Rhodotorula glutinis was used as the biocatalyst. Enantiopure (S)-styrene oxide with 98% ee was obtained with 41% yield (maximum yield = 50%) from 1.8 M racemic styrene oxide at pH 8.0, 4 degrees C in the presence of 40% (v/v) Tween 20 and 5% (v/v) glycerol.

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Properties of epoxide hydrolase from Aspergillus niger for the hydrolytic kinetic resolution of epoxides in pure organic media

Cited by 31 publications

References 42 publications

Toward advanced ionic liquids. Polar, enzyme-friendly solvents for biocatalysis

Toward advanced ionic liquids. Polar, enzyme-friendly solvents for biocatalysis

Recent developments in the asymmetric hydrolytic ring opening of epoxides catalysed by microbial epoxide hydrolase

Enantioselective resolution of racemic styrene oxide at high concentration using recombinant Pichia pastoris expressing epoxide hydrolase of Rhodotorula glutinis in the presence of surfactant and glycerol

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