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Enzymatic Synthesis of Epoxidized Metabolites of Docosahexaenoic, Eicosapentaenoic, and Arachidonic Acids
Published on: June 28, 2019
Chemo-enzymatic epoxidation-process options for improving biocatalytic productivity.
Anna E V Hagström1, Ulrika Törnvall, Mathias Nordblad
1Dept. of Biotechnology, Center for Chemistry and Chemical Engineering, Lund University, Lund, Sweden. anna.hagstrom@biotek.lu.se
Biotechnology Progress
|February 12, 2011
Summary
Enzyme inactivation by hydrogen peroxide (H(2)O(2)) hinders chemo-enzymatic epoxidation. Controlled fed-batch reactors and multistage designs significantly improved enzyme stability and productivity in solvent-free systems.
Area of Science:
- Biocatalysis and Green Chemistry
- Chemical Engineering and Process Design
Background:
- Enzyme inactivation by hydrogen peroxide (H(2)O(2)) is a major challenge in chemo-enzymatic epoxidation processes.
- Rapeseed methyl ester (RME) is used as a substrate in a solvent-free system.
Purpose of the Study:
- Investigate reaction parameters to minimize enzyme inactivation.
- Optimize operating strategies for improved reaction performance and enzyme stability.
- Enhance productivity in solvent-free chemo-enzymatic epoxidation.
Main Methods:
- Utilized a controlled fed-batch reactor to maintain specific H(2)O(2) concentrations.
- Implemented a multistage reactor design separating reaction and substrate saturation.
- Analyzed the impact of H(2)O(2) concentration on reaction rate and enzyme inactivation.
Main Results:
- Controlled fed-batch reactor maintaining H(2)O(2) at 1.5 M increased productivity to 76 g product/g biocatalyst with enhanced enzyme activity retention.
- Multistage design demonstrated strong dependence of reaction rate and enzyme inactivation on H(2)O(2) concentration.
- Significant improvements in enzyme efficiency are needed for economic feasibility.
Conclusions:
- Reactor design and controlled H(2)O(2) levels are critical for mitigating enzyme inactivation in chemo-enzymatic epoxidation.
- A 20-fold increase in enzymatic efficiency, through enzyme modification and process design, is necessary for an economically viable process.
- Solvent-free systems with optimized reactor strategies offer potential for sustainable biocatalysis.
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