Enhanced Enzymatic Synthesis of Nicotinamide in Laminar Flow Intensified Microreactors: Models and Simulations

Abstract

The intracellular level of nicotinamide adenine dinucleotide (NAD+) decreases with age, and this depletion seems to worsen during complex SARS-CoV-2 infections. Increasing the level of NAD+ via nicotinamide and nicotinamide riboside kinase routes may re-establish the antiviral poly-ADP-ribose polymerase functions of infected elderly persons and may potentially restrict SARS-CoV-2 infection by boosting innate immunity. In this work, we simulated nicotinamide synthesis in laminar flow microreactors with nitrile hydratase enzyme uniformly attached on the microchannel wall and/or immobilized on the surface of microparticles dispersed in the liquid phase. Hydrodynamic/diffusional limitations of laminar flow microreactors are greatly alleviated in intensified flow microreactors and microreactors with an enhanced enzymatic process, which greatly improves when nitrile hydratase loading on the surface of microparticles increases (more enzyme works as a free solution-phase enzyme). Enhanced nicotinamide synthesis in intensified flow microreactors generates high conversions even if an enzymatic module (attached enzyme on the channel wall or microparticle surface) does no work at optimal parameters. ©