A comparative study between kojic acid and its methylated derivatives as antioxidant related to maltol and alomaltol

Kojic acid is a natural product produced by many species of fungi and has a wide range of applications in the cosmetics, medicines, food, agriculture and chemical industries. Several biological activities are reported in the literature, mostly related to both its chelating and antioxidant capacity. This study aimed to evaluate, theoretically by Density Functional Theory (DFT) method using B3LYP functional and 6–311++g(2d,2p) basis set, the antioxidant capacity of kojic acid and three methylated derivatives comparing with maltol. The values of Highest Occupied Molecular Orbital (HOMO), Lowest Un-occupied Molecular Orbital (LUMO), Gap, Ionization Potential (IP), Bond Dissociation Energy of enolic hydroxyl (BDEOH), Hydrogen Atom Transfer (HAT), Single Electron Transfer (SET), Sequential Proton Loss-Electron Transfer (SPLET), and spin density showed that methylation in position 2 produces the derivative with greater antioxidant capacity compared to maltol.