Zeynep KALAYCIOĞLU, Nurgül KARADAŞ, Mehmet Emin ÇINAR, Sibel AYŞIL ÖZKAN, Durişehvar ÖZER ÜNAL, Ayşegül GÖLCÜ, Fatma Bedia BERKER

Electrochemical oxidation of curcuminoids: an experimental and computational investigation

ISSN: 1300-0527
Yayın Aralığı: 6
Yayıncı: TÜBİTAK

Curcuminoids, reported to have important biological properties, such as antioxidant, anti-Alzheimer, and antidiabetic properties, comprise curcumin (CRM; 1,7-bis [4-hydroxy-3-methoxyphenyl]-1,6-heptadiene-3,5-dione) and its derivatives demethoxycurcumin (DMC; (E,6E)-1-(3,4-dimethoxy-cyclohexyl)-7-(3,4-dimethoxyphenyl)hepta-1,6-diene-3,5-dione) and bisdemethoxycurcumin (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.

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