Abstract:

The gluathione peroxidase (GPx) activities of 6A,6A′-dianilino-6B,6B′-diselenide-bis-β-cyclodextrin (6-AnSeCD) in the reduction of H₂O₂, tertbutylhydroperoxide (t-BuOOH) and cumenyl hydroperoxide (CumOOH) by glutathione (GSH) were assessed in classical coupled reductase assay, and the steadystate kinetics of 6AnSeCD in the reduction of three hydrogen peroxides was studied. The 6-AnSeCD displayed best GPx activity for the reduction of CumOOH by GSH. A pingpong mechanism was observed in the steadystate kinetic studies on the 6-AnSeCDcatalyzed reactions. We further compared k_max, K_m and secondorder rate constant of 6-AnSeCD. The results show the CumOOH is the most preferred substrate for 6-AnSeCD.

Key words: gluathione peroxidase, mimic, cyclodextrin, steady state kinetics