射干总黄酮提取工艺优化及其抗氧化活性研究

Optimization of Extraction Process of Total Flavonoids from Belamcanda chinensis and Its Antioxidant Activity

采用超声辅助提取射干总黄酮,在单因素试验的基础上,采用正交试验设计,对射干总黄酮提取工艺进行优化;然后,采用优化后的工艺对射干不同部位(须根、主根、花梗、叶、花、茎)的总黄酮进行提取,通过DPPH自由基清除率和ABTS^(+)自由基清除率2个指标对射干不同部位提取物的抗氧化能力进行了比较。结果表明:射干总黄酮超声提取的最佳工艺条件为乙醇浓度60%、液料比1∶20、提取温度70℃、超声波功率80 W,该提取条件下射干不同部位的总黄酮含量具有显著差异,其中叶的总黄酮含量最高、茎的总黄酮含量相对较低。射干不同部位提取物对DPPH和ABTS^(+)自由基的清除能力存在着一定差异,其中,花梗提取物对DPPH自由基的清除能力最强,IC_(50)为0.48 mg/mL;须根和叶提取物对ABTS^(+)自由基的清除作用较好,清除率分别为97.98%和96.90%。射干总黄酮含量与其抗氧化活性的相关性分析结果显示,射干总黄酮含量与其DPPH自由基的清除能力相关不显著,但与ABTS^(+)自由基的清除能力呈极显著正相关。

Ultrasonic assisted extraction was used to extract total flavonoids from Belamcanda chinensis.On the basis of single factor experiment,orthogonal design was used to optimize the extraction process of total flavonoids.Then,the optimized process was used to extract the total flavonoids from different parts(fibrous root,taproot,pedicel,leaf,flower and stem)of B.chinensis.The antioxidant capacity of the extracts from different parts was compared through DPPH free radical scavenging rate and ABTS^(+)free radical scavenging rate.The results showed that the optimum conditions for ultrasonic extraction of total flavonoids from B.chinensis were ethanol concentration of 60%,liquid material ratio of 1:20,extraction temperature of 70℃,and ultrasonic power of 80 W.Under this extraction condition,the total flavone content in different parts had significant differences,among which the total flavone content in leaf was the highest and that in stem was relatively low.The scavenging ability of extracts from different parts of B.belamcanda to DPPH and ABTS^(+)free radicals was different,among which,the pedicel extract had the strongest scavenging ability to DPPH free radicals,and the IC_(50) was 0.48 mg/mL.The extracts of fibrous roots and leaves had good scavenging effects on ABTS^(+)free radicals,with the scavenging rates of 97.98%and 96.90%,respectively.The correlation analysis showed that the total flavone content of B.chinensis had no significant correlation with its DPPH free radical scavenging ability,but had a very significant positive correlation with the ABTS^(+)free radical scavenging ability.