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

Abstract

Carrier-free enzyme immobilization techniques are an important development in the field of efficient and streamlined continuous synthetic processes using microreactors. Here, the use of monolithic, self-assembling all-enzyme hydrogels is expanded to phenolic acid decarboxylases. This provides access to the continuous flow production of p-hydroxystyrene from p-coumaric acid for more than 10 h with conversions ≥98% and space time yields of 57.7 g·(d·L)−1. Furthermore, modulation of the degree of crosslinking in the hydrogels resulted in a defined variation of the rheological behavior in terms of elasticity and mesh size of the corresponding materials. This work is addressing the demand of sustainable strategies for defunctionalization of renewable feedstocks.

Microfluidic cultivation and analysis of productive biofilms

“…The EsPAD selectively converts HCA 4 to 4‐vinylphenol (VP) 5 (Figure 2c) (Peng et al, 2019). All three enzymes have been immobilized in isolated form in biocatalytic flow reactors in previous work and showed enzymatic activity for at least 40 h, highlighting the stability of these enzymes (Bitterwolf et al, 2019; Mittmann, Gallus, et al, 2019; Mittmann, Hu, et al, 2019; Peschke et al, 2018; Peschke, Rabe, et al, 2017; Peschke, Skoupi, et al, 2017).…”

Synthetic Enzyme‐Catalyzed CO2 Fixation Reactions

“…It may be necessary to employ green organic co‐solvents or biphasic systems to improve substrate solubility, prevent product inhibition and enhance the performance of the system. Additionally, improving performance of enzymatic carboxylation maybe achieved using immobilization techniques, [142] and investigating the suitability of batch or flow processes for individual reactions.…”

The rise of continuous flow biocatalysis – fundamentals, very recent developments and future perspectives

“…138 Reaction Chemistry & Engineering Review remarkable that these hydrogels have a three-dimensional structure leading to a significant increase in the enzymatic activity per reactor volume. 148 Hence, they offer an effective use of volume occupied by the enzymes immobilized in gels.…”