5α-reductase inhibitory compounds produced by polymerization of resveratrol with horseradish peroxidase

To produce 5alpha-reductase inhibitory compounds. resveratrol was enzymatically oxidized in a horseradish peroxidase (HRP)/H2O2 system. Ethyl acetate extract of the oxidation products showed strong 5alpha-reductase inhibitory activity with 10%-15% organic solvents in the system, whereas without organic solvent little inhibitory activity was exhibited. The optimum pH of enzymatic oxidation for acquisition of the inhibitory activity was 4.5. The inhibitory compounds were isolated and identified as resveratrol traps-dehydrodimer and resveratrol cis-dehydrodimer by comparing with published nuclear magnetic resonance data. The two resveratrol dehydrodimers have stronger inhibitory activity than natural resveratrol dimers and trimers found in Shorea species.