Abstract:
Curcumin influences the transition point, the concentration of denaturant required to effect 50percent of the total change, of myoglobin denaturation. Curcumin enhances absorbance of myoglobin at 280nm with a binding constant K=3.0×104M-1 whereas fluorescence of curcumin is quenched by myoglobin with a Stern-Volmer association constant of 2.5×105M-1. Unfolding process of myoglobin-curcumin induces a recovery in fluorescence lifetime loss. The gain in time-resolved fluorescence lifetime during unfolding has been again lost during refolding of curcumin-myoglobin complex by dilution process suggesting partial reversibility of unfolding process for both myoglobin and curcumin-myoglobin complex. © 2012 Elsevier B.V.