超声法提取小叶苦丁茶多糖及其抗氧化活性研究

Ultrasonic extraction of polysaccharide from Ligustrum robustum and its antioxidant activity study

目的通过单因素实验和响应面设计优化超声法提取小叶苦丁茶多糖,并对其进行体外抗氧化活性研究。方法分别考察超声时间、超声功率、液固比3个因素对提取率的影响,再通过实验进行响应面优化设计,得到最佳的提取条件;考察多糖提取物对DPPH自由基、ABTS自由基的清除能力及金属离子的螯合能力,用于评价其体外抗氧化活性。结果多糖的最佳提取条件为:超声时间41 min,超声提取功率240 W,液固比31 mL/g,在此条件下,多糖的提取率为15.20%。体外抗氧化活性评价结果显示其清除DPPH·、ABTS^(·+)自由基清除的IC_(50)值分别为(47.22±1.21)μg/mL和(12.74±1.04)μg/mL,对金属离子螯合的IC_(50)值为(121.54±0.98)μg/mL。结论该提取工艺简便、高效、稳定、省时,所获得的小叶苦丁茶多糖具有潜在体外抗氧化活性。

Objective To optimize the ultrasonic extraction process of polysaccharide from Ligustrum robustum based on the single factor and response surface design.And the in vitro antioxidant activity of polysaccharide was investigated.Methods The effects of three factors,namely,ultrasonic time,ultrasonic power and liquid-to-solid ratio,on the extraction rate were investigated separately.Then the response surface optimization design was carried out to obtain the optimal extraction conditions.Moreover,the in vitro antioxidant activities of polysaccharide extract were evaluated through the investigation by DPPH free radical scavenging ability,ABTS free radical scavenging ability and metal ion chelating ability.Results The optimal extraction conditions of polysaccharides were:ultrasonic time 41 min,ultrasonic extraction power 240 W,liquid-solid ratio 31 mL/g,and the extraction rate of polysaccharides was 15.20%under these conditions.The results of in vitro antioxidant activity showed that the IC_(50)of DPPH·and ABTS^(·+)were(47.22±1.21)μg/mL and(12.74±1.04)μg/mL,respectively.The IC_(50)for metal ion chelation was(121.54±0.98)μg/mL.Conclusion The extraction process has the advantages of being simple,efficient,stable and time-saving,and the obtained polysaccharides from Ligustrum robustum has potential in vitro antioxidant activity.