Sustainable and Continuous Synthesis of Enantiopure l‐Amino Acids by Using a Versatile Immobilised Multienzyme System

The enzymatic synthesis of -amino acids appears as a sustainable and efficient alternative to chemical processes, where achieving enantiopure products is a hard task. To more efficiently adress this synthesis, we desinged and fabricate a hierarchical architecture that irreversibly co-immobilises an amino acid dehydrogenase with polyethyleneimine on porous agarose beads. The cationic polymer acts as an irreversible anchoring layer for the formate dehydrogenase. In this architecture, the two enzymes and the polymer co-localise across the whole microstructure of the porous carrier. This multi-functional heterogeneous biocatalyst was kinetically characterized and applied to the enantioselective synthesis of a variety of canonical and non-canonical -amino acids both in discontinuous(batch) and continuous modes. The co-immobilised bi-enzymatic system conserves more than 50% of its initial effectiveness after 5 batch cycles and 8 days of continuous operation. Additionally, we semi-quantitatively calculated the environmental impact of this process and compared it with the state-of-art.