黑老虎花总黄酮超声辅助提取工艺优化及其抗氧化性研究

目的:优化黑老虎花总黄酮提取工艺及研究其体外抗氧化活性。方法:通过单因素实验（超声时间、料液比、乙醇浓度、超声温度）及正交试验优化黑老虎花总黄酮的最佳提取工艺；评估最优条件下黑老虎花总黄酮对ABTS、DPPH自由基的清除能力。结果:超声辅助提取最优工艺为:全开期（6月份）、超声时间45 min、料液比1:30 mg/mL、超声温度60 ℃、乙醇浓度85%，该条件下提取量为19.25 mg/g。在0.8 mg/mL，最优条件下黑老虎花总黄酮对DPPH自由基清除率为82.1%，清除能力为维生素C的87.9%；在0.4 mg/mL，对ABTS自由基清除能力与维生素C相当。黑老虎花总黄酮对DPPH、ABTS自由基的IC₅₀分别为0.13、0.046 mg/mL。结论:该提取方法可行，提取工艺条件可靠，黑老虎花总黄酮可作为天然抗氧化剂开发来源。

Study on Optimization of Ultrasonic-Assisted Extraction Technology of Total Flavonoids from Kadsura coccinea Flowers and Its Antioxidant Activity

Objective: To optimize the extraction technology and study the antioxidant activity of total flavonoids from the Kadsura coccinea flowers. Methods: The optimum extraction process of total flavonoids from the Kadsura coccinea flowers was optimized by single factor test (ethanol concentration, ultrasonic time, solid-liquid ratio, ultrasonic temperature) and orthogonal experiment. The scavenging ability of total flavonoids on ABTS and DPPH free radicals was evaluated. Results: Full opening period(June), ultrasonic time 45 min, solid-liquid ratio 1:30 mg/mL, ultrasonic temperature 60 ℃, ethanol concentration 85% were the optimal extraction conditions, the extraction quantity of optimum extraction condition was 19.25 mg/g. When the concentration of total flavonoids was 0.8 mg/mL, the scavenging rate on DPPH free radical was 82.1%, it was 87.9% of that of vitamin C. When the concentration of total flavonoids was 0.4 m, the scavenging ability on ABTS free radical was similar to that of vitamin C. The IC₅₀ of total flavonoids from the Kadsura coccinea flowers against DPPH free radical and ABTS radical were 0.13, 0.046 mg/mL, respectively.Conclusion: The extraction method is feasible and the extraction conditions are reliable, the total flavonoids of Kadsura coccinea flowers can be used as a source of natural antioxidants.