Efficient enzymatic acrylation through transesterification at controlled water activity.

Area of Science:

• Biocatalysis
• Enzyme kinetics
• Chemical synthesis

Background:

• Enzymatic acrylation is crucial for the chemical industry.
• Direct esterification with acrylic acid faces challenges like slow rates and inhibition at high concentrations.

Purpose of the Study:

• To investigate and optimize enzymatic acrylation of 1-octanol using different acrylic group donors.
• To determine the effect of water activity on ester synthesis rates for various substrates.

Main Methods:

• Utilized immobilized Candida antarctica lipase B (Novozym 435) as a biocatalyst.
• Compared acrylation rates using acrylic acid versus ethyl acrylate as the acrylic source.
• Investigated the impact of varying water activity on reaction kinetics.

Main Results:

• Acrylation of 1-octanol with ethyl acrylate was up to ten times faster than with acrylic acid.
• Optimal water activity for esterification with acrylic acid was 0.75.
• Optimal water activity for transesterification with ethyl acrylate was 0.3, and for propionic acid esterification was 0.45.

Conclusions:

• Ethyl acrylate is a more efficient acrylic group donor for enzymatic acrylation of 1-octanol.
• Water activity is a critical factor influencing enzyme specificity, substrate solvation, and mass transfer, thereby affecting optimal reaction conditions.