IMPROVEMENT OF THE TOTAL TURNOVER NUMBER AND SPACE-TIME YIELD FOR CHLOROPEROXIDASE CATALYZED OXIDATION

Chloroperoxidase from Caldariomyces fumago was applied for the oxidati on of indole to oxindole using hydrogen peroxide as the oxidant in aqu eous t-butyl alcohol medium. Different ways of adding the oxidant, var ious reactor types, and the use of a hydrogen peroxide-stat were compa red, resulting in a 20-fold increase of the total turnover number (ttn ) and space-time yield (sty). The highest ttn of >860,000 was obtained in a fed-batch reactor, whereas the highest sty of 120 g/(L.d) was re ached in a continuously operated enzyme membrane reactor. The results were compared to other enzyme systems already established for the synt hesis of amino acids and carbohydrates. (C) 1997 John Wiley & Sons, In c.