Two membrane electrochemical reactors (MER) were designed and applied to HLADH-catalysed reduction of cyclohexanone to cyclohexanol. The regeneration of the cofactor NADH was ensured electrochemically, using either methyl viologen or a rhodium complex as electrochemical mediator. A semi-permeable membrane (dialysis or ultra-filtration) was integrated in the filter-press electrochemical reactor ...

The enzymatic production of fructose 1,6-diphosphate (FDP) from glucose was performed in a batch reactor and a semibatch reactor using the crude cell extract of Bacillus stearothermophilus which contains all four enzymes required for the synthesis. The experimental results of the yield and the time courses of FDP production obtained using various enzyme concentrations were in good agreement wit...

The limited deamidating ability of peptidoglutaminase {PGase) toward intact food proteins (0-6% deamidation) can be significantly enhanced by prior protein hydrolysis and altering protein conformation by such means as moist heat. PGase deamidation increases protein solubility and improves emulsifying and other physical properties under mildly acidic conditions. A batch reactor method was develo...

Despite their sustainability, the potential of biocatalytic processes in industrial production is far from being realized. The main challenges this field are development highly active, robust, and stable biocatalysts, efficient regeneration cofactors, prevention biocatalyst deactivation under harsh conditions. In addition to engineering, enzyme cell immobilization plays a crucial role process f...

Enzyme activity and stability in a membrane reactor for wine aroma enhancement can be higher than when the enzyme is present in a free state since the catalyst would only be in contact with the low molecular mass components of this beverage. To test this hypothesis, the activity and stability of two commercial -glucosidases were measured in the presence of Tannat wine and of its low molecular m...

Many natural and synthetic estrogens are amenable to oxidation through the catalytic action of oxidative enzymes such as the fungal laccase Trametes versicolor. This study focused on characterizing the conversion of estradiol (E(2)) using laccase that had been immobilized by covalent bonding onto silica beads contained in a bench-scale continuous-flow packed bed reactor. Conversion of E(2) acco...

Two commercial proteases from Bacillus licheniformis (Alcalase 2.4 L FG and Alcalase 2.5 L, Type DX) were screened for the production of Z-Ala-Phe-NH2 in batch reaction. Alcalase 2.4 L FG was the most efficient enzyme for the C-terminal amidation of Z-Ala-Phe-OMe using ammonium carbamate as ammonium source. Immobilization of protease has been achieved by the sol-gel method, using dimethyldimeth...

An aminotransferase capable of transaminating 2-oxo-4-[(hydroxy)(methyl)phosphinoyl]butyric acid to L-phosphinothricin [L-homoalanine-4-yl-(methyl)phosphinic acid], the active ingredient of the herbicide Basta (Hoechst AG), was purified to apparent homogeneity from Escherichia coli K-12. The enzyme catalyzes the transamination of L-phosphinothricin and various analogs with 2-ketoglutarate as th...