A Phenolic Acid Decarboxylase-Based All-Enzyme Hydrogel for Flow Reactor Technology

Area of Science:

• Biocatalysis and Enzyme Engineering
• Materials Science
• Sustainable Chemistry

Background:

• Carrier-free enzyme immobilization is crucial for efficient continuous synthesis in microreactors.
• All-enzyme hydrogels offer a promising platform for streamlined enzymatic processes.

Purpose of the Study:

• To expand the application of self-assembling all-enzyme hydrogels to phenolic acid decarboxylases.
• To develop a continuous flow process for p-hydroxystyrene production from p-coumaric acid.
• To investigate the relationship between hydrogel crosslinking and rheological properties.

Main Methods:

• Utilized monolithic, self-assembling all-enzyme hydrogels for enzyme immobilization.
• Employed phenolic acid decarboxylases for the conversion of p-coumaric acid.
• Performed continuous flow reactions in microreactors.
• Modulated hydrogel crosslinking to alter rheological behavior.

Main Results:

• Achieved continuous flow production of p-hydroxystyrene from p-coumaric acid for over 10 hours.
• Reported high conversions (≥98%) and space-time yields (57.7 g·(d·L)⁻¹).
• Demonstrated tunable rheological properties (elasticity, mesh size) by adjusting hydrogel crosslinking.

Conclusions:

• Self-assembling all-enzyme hydrogels are effective for carrier-free immobilization of phenolic acid decarboxylases.
• This approach enables efficient and sustainable continuous production of valuable chemicals from renewable feedstocks.
• Hydrogel material properties can be precisely controlled to optimize biocatalytic performance.