Electrochemical oxidation of curcuminoids: an experimental and computational investigation

Authors : Zeynep KALAYCIOĞLU, Nurgül KARADAŞ, Mehmet Emin ÇINAR, Sibel Ayşil ÖZKAN, Durişehvar Özer ÜNAL, Ayşegül GÖLCÜ, Fatma Bedia ERİM

Pages : 834-845

View : 20 | Download : 9

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :Curcuminoids, reported to have important biological properties, such as antioxidant, anti-Alzheimer, and antidiabetic properties, comprise curcumin insert ignore into journalissuearticles values(CRM; 1,7-bis [4-hydroxy-3-methoxyphenyl]-1,6-heptadiene-3,5-dione); and its derivatives demethoxycurcumin insert ignore into journalissuearticles values(DMC; insert ignore into journalissuearticles values(E,6E);-1-insert ignore into journalissuearticles values(3,4-dimethoxy-cyclohexyl);-7-insert ignore into journalissuearticles values(3,4-dimethoxyphenyl);hepta-1,6-diene-3,5-dione); and bisdemethoxycurcumin insert ignore into journalissuearticles values(BDMC; 1,7-bis[4-hydroxyphenyl]-1,6-heptadiene-3,5-dione);. Their electrochemical oxidations are thoroughly explored by applying cyclic and differential pulse voltammetric techniques. The dependence of current intensities and potentials on pH, concentration, scan rate, and nature of the buffer was investigated. The outcome is supported by density functional theory computations indicating the transfer of 4-e$^{-}$/H$^{+}$, 6-e$^{-}$/H$^{+}$, and 8-e$^{-}$/H$^{+}$ couples involved in the oxidation mechanisms of CRM, DMC, and BDMC, respectively, leading to the formation of the same oxidized product.
Keywords : Cyclic voltammetry, curcuminoids, density functional theory, differential pulse voltammetry