白骨壤叶中生物碱的提取及抗氧化活性研究

Study on Extraction and Antioxidant Activity of Alkaloids fromLeaves of Avicennia marina

[目的]确定白骨壤叶中生物碱的提取工艺和初步鉴定该物质的活性。[方法]以生物碱的提取得率为评价指标,采用正交试验法,优选超声提取白骨壤中生物碱的工艺,考察乙醇体积分数、超声提取时间、超声提取温度和溶液pH对提取工艺的影响。采用硫酸亚铁-水杨酸法、DPPH反应法比较体外清除自由基作用,测定白骨壤叶中总生物碱的抗氧化活性。[结果]影响白骨壤叶中生物碱提取率的主要因素是提取溶液pH,最佳提取工艺条件为乙醇体积分数70%、提取时间20 min、提取温度70℃、提取溶液pH=3。优选之后的提取工艺最佳得率为14.12%,方便快捷可行、稳定性好。清除自由基的强弱为DPPH自由基大于羟基自由基。[结论]该研究为生物碱的应用提供理论依据。

[Objective]The research aimed to determine the extraction process of alkaloids in the leaves of Avicennia marina and the preliminary identification of the activity of the substance. [Method]Taking the extraction rate of alkaloids as the evaluation index,orthogonal experiment was used to optimize the ultrasonic extraction of alkaloids from Avicennia marina. The effects of ethanol volume fraction,ultrasonic extraction time,ultrasonic extraction temperature and solution pH on extraction process were investigated. The antioxidant activity of total alkaloids in Avicennia marina was determined by the method of ferrous sulfate-salicylic acid oxidation,DPPH reaction in vitro. [Result]The main factor affecting the extraction rate of alkaloids in Avicennia marina leaves was the pH of the extraction solution. The optimal extraction conditions were ethanol concentration 70%,extraction time 20 min,extraction temperature 70 ℃,extraction solution pH = 3. The optimum extraction rate after optimization was 14. 12%,which was convenient,feasible and stable. The order of scavenging free radicals was DPPH radical hydroxyl radical. [Conclusion]The study provides a theoretical basis for the application of alkaloids.