Electrocatalytic NAD(P)H regeneration for biosynthesis

The highly efficient chemoselectivity, stereoselectivity, and regioselectivity render enzyme catalysis an ideal pathway for the synthesis of various chemicals in broad applications. While the cofactor of an enzyme is necessary but expensive, the conversed state of the cofactor is not beneficial for the positive direction of the reaction. Cofactor regeneration using electrochemical methods has the advantages of simple operation, low cost, easy process monitoring, and easy product separation, and the electrical energy is green and sustainable. Therefore, bioelectrocatalysis has great potential in synthesis by combining electrochemical cofactor regeneration with enzymatic catalysis. In this review, we detail the mechanism of cofactor regeneration and categorize the common electron mediators and enzymes used in cofactor regeneration. The reaction type and the recent progress are summarized in electrochemically coupled enzymatic catalysis. The main challenges of such electroenzymatic catalysis are pointed out and future developments in this field are foreseen.