Abstract: The epoxidation of cyclohexene catalyzed by a vanadium bromoperoxidase from the red algae Corallina officinalis has been investigated. The reaction was performed in a water-organic solvent biphasic system. The effects of oxidants and their loading method, pH, temperature, and the concentration of vanadium bromoperoxidase and KBr on the epoxidation were studied. The optimal conditions were as follows: the reaction temperature was 55 ℃, and 50 μl of 2.29 mol/L H2O2 was added every 10 min to the Tris-HCl buffer at pH 6.0 containing 50 mmol/L of KBr and 32 U/ml of the enzyme (final concentration). Under these conditions, the maximum epoxy cyclohexane yield and selectivity were 41.5% and 82.2%, respectively.

Key words: bromoperoxidase, cyclohexene, epoxidation, epoxy cyclohexane