Abstract: Objective: To study the antioxidant activity of seed oil from Eucommia ulmoides Oliver key fruits in vitro. Methods: The reducing power and superoxide anion radical scavenging rate of the oil were measured by trichloroacetic acid method and NBT photoreduction method, respectively. The scavenging rate against hydroxyl radicals generated in Fenton system was determined by NBT photoreduction method. The cell membrane-protecting effect was determined by oxidative hemolysis of erythrocytes and the inhibitory effect against lipid peroxidation was evaluated by determining the relative content of MDA in mouse liver homogenate. Vitamin C was used as the control. Results: The oil had strong reducing power so that it could remarkably eliminate superoxide anion free radicals and hydroxyl free radicals. In addition, the oil could also inhibit the generation of MDA in mouse liver homogenate, reduce H2O2-mediated oxidation hemolysis of erythrocytes and spontaneous lipid peroxidation of mouse liver tissue in a dose-dependent manner. The oil at the concentration of 9 mg/mL revealed the strongest effect. Conclusion: Seed oil from Eucommia ulmoides Oliver key fruits has antioxidant capability in vitro.

Key words: seed oil from Eucommia ulmoides Oliver key fruits, antioxidant capability, free radicals