Increased enantioselectivity and remarkable acceleration of lipase-catalyzed transesterification by using an imidazolium PEG-alkyl sulfate ionic liquid.
Several types of imidazolium salt ionic liquids were prepared derived from poly(oxyethylene)alkyl sulfate and used as an additive or coating material for lipase-catalyzed transesterification in an organic solvent. A remarkably increased enantioselectivity was obtained when the salt was added at 3-10 mol % versus substrate in the Burkholderia cepacia lipase (lipase PS-C)-catalyzed transesterification of 1-phenylethanol by using vinyl acetate in diisopropyl ether or a hexane solvent system. In particular, a remarkable acceleration was accomplished by the ionic liquid coating with lipase PS in an iPr(2)O solvent system while maintaining excellent enantioselectivity; it reached approximately 500- to 1000-fold acceleration for some substrates with excellent enantioselectivity. A similar acceleration was also observed for IL 1-coated Candida rugosa lipase. MALDI-TOF mass spectrometry experiments of the ionic-liquid-coated lipase PS suggest that ionic liquid binds with lipase protein.
Itoh
Toshiyuki
T
Department of Materials Sciences, Faculty of Engineering, Tottori University, 4-101 Koyama-minami, Tottori 680-8552, Japan. titoh@chem.tottori-u.ac.jp
Matsushita
Yuichi
Y
Abe
Yoshikazu
Y
Han
Shi-Hui
SH
Wada
Shohei
S
Hayase
Shuichi
S
Kawatsura
Motoi
M
Takai
Shigeomi
S
Morimoto
Minoru
M
Hirose
Yoshihiko
Y
D002175:Candida / Q000201:enzymology; D002384:Catalysis; D004951:Esterification; D007093:Imidazoles / Q000737:chemistry*; D008049:Lipase / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000737:chemistry*; D013237:Stereoisomerism; D013431:Sulfates / Q000737:chemistry*
D007093:Imidazoles; D013431:Sulfates; D011092:Polyethylene Glycols; D008049:Lipase