Protective effects of equimolar mixtures of monomer and dimer of dehydrozingerone with α-tocopherol and/or ascorbyl palmitate during bulk lipid autoxidation

• Protective effects of monomer and dimer of dehydrozingerone were studied.
• Antioxidant activity of dimer was higher than of monomer.
• Mixtures of monomer with α-tocopherol and ascorbyl palmitate showed synergism.
• Regeneration of α-tocopherol was proved with determination of its content by HPLC.

Protective effects of recently synthesised dehydrozingerone, M1OH (which is one half of the molecule of curcumin) and dimer of dehydrozingerone, D1(OH)2, as individual compounds (1 mM) and as equimolar binary (1:1) and ternary (1:1:1) mixtures with α-tocopherol (TOH) and/or ascorbyl palmitate (AscPH), were studied during bulk lipid autoxidation at 80 °C. The highest oxidation stability of lipid substrate, in the presence of individual compounds, was found for TOH, followed by D1(OH)2 and M1OH, determined from the main kinetic parameters (antioxidant efficiency, reactivity and capacity). AscPH did not show any protective effect. Synergism was obtained for the binary mixtures of (TOH + AscPH) [42.4%], (M1OH + TOH) [32.4%] and (M1OH + AscPH) [35.6%] and for the ternary mixture of (M1OH + TOH + AscPH) [28.7%]. Different protective effects observed were explained on the basis (of results) of TOH regeneration and its content determined by HPLC. These antioxidant binary and ternary mixtures can be used as functional components of foods with health-promoting effects.