Stereoselective Processes Catalyzed by Nonhydrolytic Enzymes

For example, horse liver alcohol dehydrogenase (HLADH) was noncovalently immobihzed on a membrane and packed into a PBR [74] operated in a recirculated loop mode for the reduction of racemic 2-phenyl-tetrahydropyran-4-one 1 in the presence of NADH. The HLADH-reactor coupled with an enzymic cofactor regeneration system in the mobile phase could convert the substrate to the enantiopure (S,S)- and (R,S)-2. The immobilized HLADH reactor was stable over 6 months when stored at 5 °C. 

An agitated tube reactor (ATR) system was investigated for the KR of D,L-alanine 3 by D-amino acid oxidase [75]. The improved mass transfer under flow conditions 

1 Horse liver alcohol dehydrogenase (HLADH) PER (recirculated loop) (1.5-83) 99 [74] 

3 D-Amino acid oxidase (DAAO) Agitated tube reactor (agitated gas-liquid phases) 50 99 [75] 

5 Thermophilic alcohol dehydrogenase (TADH) Segmented flow capillary reactor 45 — 99 [76] 

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