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Published on: July 24, 2021
Working at controlled water activity in a continuous process: the gas/solid system as a solution.
1Laboratoire du Génie Protéique et Cellulaire, Université de La Rochelle, Avenue Marillac, 17000 La Rochelle, France.
Biotechnology and Bioengineering
|March 5, 1995
Summary
This study explored enzymatic transesterification using Fusarium solani cutinase and Candida cylindracea lipase in a continuous gas/solid bioreactor. Optimal water activity (a(w)) and immobilization techniques were key for biocatalyst stability and activity in biotransforming volatile esters.
Area of Science:
- Biocatalysis and enzyme technology
- Chemical engineering and process development
- Green chemistry and sustainable processes
Background:
- Enzymatic transesterification offers a sustainable route for ester synthesis.
- Continuous gas/solid bioreactors provide efficient reaction environments.
- Enzyme immobilization is crucial for enhancing stability and reusability.
Purpose of the Study:
- To investigate the use of Fusarium solani cutinase and Candida cylindracea lipase in a continuous gas/solid bioreactor for transesterification.
- To evaluate the impact of immobilization techniques and water activity (a(w)) on enzyme performance and stability.
- To explore the potential of this system for the biotransformation of volatile esters.
Main Methods:
- Utilized Fusarium solani cutinase and Candida cylindracea lipase.
- Employed a continuous gas/solid bioreactor with a packed enzymatic preparation.
- Investigated various immobilization conditions and controlled water activity (a(w)).
- Compared immobilized enzymes with non-supported enzymes.
Main Results:
- Enzymatic activity was highly dependent on water activity (a(w)).
- Biocatalyst stability was significantly influenced by water activity and immobilization method.
- Optimal water requirements for free and adsorbed enzymes correlated with hydration coverage and sorption isotherms.
- Demonstrated successful operation of a continuous system at controlled water activity.
Conclusions:
- A continuous gas/solid bioreactor system operating at controlled water activity is feasible for enzymatic transesterification.
- Water activity is a critical parameter for optimizing enzyme activity and stability in this system.
- Lipolytic enzymes in this continuous system represent a novel approach for volatile ester biotransformation.
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