Majumder AB, Shah S, Gupta MN. Enantioselective transacetylation of (R,S)-beta-citronellol by propanol rinsed immobilized Rhizomucor miehei lipase.
Chem Cent J 2007;
1:10. [PMID:
17880741 PMCID:
PMC1994055 DOI:
10.1186/1752-153x-1-10]
[Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2007] [Accepted: 04/18/2007] [Indexed: 11/14/2022] Open
Abstract
Background
Use of enzymes in low water media is now widely used for synthesis and kinetic resolution of organic compounds. The frequently used enzyme form is the freeze-dried powders. It has been shown earlier that removal of water molecules from enzyme by rinsing with n-propanol gives preparation (PREP) which show higher activity in low water media. The present work evaluates PREP of the lipase (from Rhizomucor miehei) for kinetic resolution of (R,S)-β-citronellol. The acylating agent was vinyl acetate and the reaction was carried out in solvent free media.
Results
The PREP, with 0.75% (v/v, reaction media) water, was indeed found to be more efficient and gave 95% conversion to the ester. Using this PREP, with no added water, 90% ee for (R)-(+)-β-citronellyl acetate at 45% conversion (E = 42) was obtained in 4 h. The control with freeze-dried enzyme, with zero water content, gave 78% ee at 30% conversion (E = 13). FT-IR analysis showed that PREP had retained the α-helical content of the enzyme. On the other hand, freeze-dried enzyme showed considerable loss in the α-helical content.
Conclusion
The results show that PREP may be a superior biocatalyst for enantioselective conversion by enzymes in low-water media.
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