Abstract: Herein, we investigated the protective effects of tocopheryl (VE), α-tocopheryl succinate (α-TOS) and tocopheryl polyethylene glycol 1000 succinate (TPGS) on free radical-induced oxidative damage to protein, lipid and DNA, as well as the inhibitory effect on the proliferation of human HepG2 hepatoma cells. The results showed that TPGS had the most protective effect on oxidative damage to biological macromolecules, followed by α-TOS and VE. Both α-TOS and TPGS could significantly decrease cell viability (P < 0.05), and TPGS was more effective. However, VE showed little effect on cell activity (P ﹥ 0.05). This could be due to the amphipathicity of TPGS, whose hydrophobic ends are adsorbed on the surface of biological macromolecules, while the hydrophilic ends are fully extended in the buffer, causing large steric hindrance to protect the biological macromolecules from being attacked by free radicals. Because of its good water solubility, TPGS could easily pass through the biofilm, increasing its effective concentration in HepG2 cells. This work will provide a theoretical basis for the application of tocopheryl derivatives in healthy nutritious foods and pharmaceuticals.

Key words: tocopheryl, α-tocopheryl succinate, tocopheryl polyethylene glycol 1000 succinate, biological macromolecules, HepG2 cells