Abstract:This study utilized Epimedium as the raw material，with the yield of total flavonoids serving as the evaluation index. The ultrasonic method was employed to extract the total flavonoids from Epimedium. The extraction conditions were optimized through single-factor experiments and orthogonal experiments. The in vitro antioxidant activity of the total flavonoids was assessed using the DPPH free radical scavenging assay，ABTS+free radical scavenging assay，O2- free radical scavenging assay，and total reducing capacity test. The results demonstrated that the optimal extraction process for the total flavonoids from Epimedium involved a solid-to-liquid ratio of 1∶30（g/mL），an ultrasonic temperature of 50 ℃，an ultrasonic time of 40 min，and an ethanol concentration of 60%. Under these conditions，the yield of total flavonoids reached（10.39±0.01）%.The antioxidant results demonstrated that the total flavonoids extracted from Epimedium exhibited a robust total reducing capacity.Specifically，at a concentration of 1.040 mg/mL，the scavenging efficiency of DPPH free radicals reached（75.15±0.43）%；the scavenging efficiency of ABTS+free radicals reached（71.19±1.38）%，and the scavenging efficiency of O2-free radicals reached（81.82±0.95）%.These findings indicated that the total flavonoids from Epimedium possessed significant antioxidant activity.