Preparative application of 2-hydroxybiphenyl 3-monooxygenase with enzymatic cofactor regeneration in organic-aqueous reaction media

Catalytic Hydroxylation in Biphasic Systems using CYP102A1 Mutants

“…[54] While volumetric productivities reported here are quite low (maximum 0.15 g l -1 h -1 ), higher values found in literature (up to 1 g l -1 h -1 ) [8] are usually calculated for reaction times of 10 h or less compared to up to 100 h in our P450-mediated approach.Switching the cofactor specificity of CYP102A1 to NADH allows to reduce the cofactor costs to about 20%. Further investigations concerning the stability and general applicability of the NAD + -dependent reaction system are required.…”

Rational Design and Engineering of Quantum‐Dot‐Sensitized TiO2 Nanotube Arrays for Artificial Photosynthesis

“…For example, conventional biocatalytic regeneration methods have critical problems such as by-product formation and the requirement of a secondary enzyme, which cause an increase in regeneration cost and pose a signifi cant hurdle for their practical implementation. [10][11][12] To avoid such problems, researchers investigated electrochemical [13][14][15] methods that use the reducing power of electrons supplied from the electrode connected to an external power supply for cofactor regeneration. Compared to the electrochemical methods, photochemical regeneration is considered to be more promising in terms of scale-up of the reactor and energy consumption because it utilizes a renewable energy source (i.e., solar energy) without complex design and installation of the reactor for the external power supply.…”

“…Thus, numerous efforts have been made over the past decades to accomplish in situ cofactor regeneration from their oxidized counterpart. [6][7][8][9] For example, researchers found that NAD(P)H can be successfully regenerated by introducing secondary enzymes [10][11][12] that reduce its oxidized counterpart (i.e., NAD(P) + ) or electrodes [13][14][15] with an external power supply into reaction media. However, these approaches present intrinsic drawbacks (e.g., by-product formation and requirement of secondary enzymes for biocatalytic regeneration, as well as extremely low yield and high overpotential for electrochemical regeneration) that hindered their practical application beyond the laboratory scale.…”

H2‐driven cofactor regeneration with NAD(P)+‐reducing hydrogenases

“…A widely used system involves the coupling of NAD + reduction with the oxidation of formate to CO 2 by formate dehydrogenase (FDH), but this system suffers from the low activity of this enzyme and solution acidification by the product, CO 2 . Additional enzyme‐coupled cofactor regeneration systems have been developed on the basis of phosphite dehydrogenases , ADHs , glucose 6‐phospate dehydrogenase , and glucose dehydrogenases . However, these NADH regeneration approaches show poor atom efficiencies, and also generate byproducts that must be separated from the product of interest, thereby compromising the economic and environmental viability for applications in bulk synthesis .…”

“…A widely used system involves the coupling of NAD + reduction with the oxidation of formate to CO 2 by formate dehydrogenase (FDH), but this system suffers from the low activity of this enzyme and solution acidification by the product, CO 2 [12,13]. Additional enzyme-coupled cofactor regeneration systems have been developed on the basis of phosphite dehydrogenases [14,15], ADHs [16], glucose 6-phospate dehydrogenase [17,18], and glucose dehydrogenases [19,20].…”