山楂多糖提取工艺优化及其抗氧化活性研究

Optimization on Extraction Process and Antioxidant Activity of Hawthorn Polysaccharides

目的:优化热水浸提法提取山楂多糖的最佳工艺条件,并研究其结构和体外抗氧化活性。方法:在单因素试验的基础上,以水浴温度、水浴时间、料水比、冷浸时间为因素,通过正交试验设计优化其提取工艺;多糖经纯化后分别采用GPC、GC-MS分析其分子量和单糖组成,并通过对超氧自由、羟自由基、DPPH(1,1-二苯基-2-三硝基苯肼)自由基清除试验测定山楂多糖的抗氧化活性。结果:最佳提取条件为浸提温度90℃、浸提时间6 h、料水比1∶20、冷浸时间为13 h,此条件下提取的多糖经过纯化后,其分子量为5.59×10^(4) Da,单糖含量比例(阿拉伯糖∶木糖∶甘露糖∶葡萄糖∶半乳糖)为1∶1∶28∶8∶12。经测定,多糖具有一定的超氧自由基、羟自由基、DPPH自由基体外清除能力,在0.5~2.5 mg/mL的浓度范围内,清除率分别为12.3%~37.9%、12.3%~40.9%、15.3%~42.6%,说明抗氧化活性较好。结论:本研究可为山楂资源的开发利用和山楂多糖的药理研究提供科学依据。

[Objective]To study the optimum process conditions for extraction of polysaccharides from hawthorn by hot water extraction,and study its structure and antioxidant activity in vitro.[Method]On the basis of single factor experiment,the extraction process was optimized by orthogonal experiment design with water extraction temperature,water extraction time,feed water ratio and cold immersion time.After purification,the polysaccharides were analyzed by GPC and GC-MS for molecular weight and monosaccharide composition.The antioxidant activity of HP was determined by superoxide free radical,hydroxyl radical,DPPH free radical scavenging test.[Result]The optimum extraction conditions were extraction temperature 90℃,extraction time 6 h,ratio of material to water 1∶20,cold soaking time 13 h.After purification of the polysaccharide extracted under this condition,the molecular weight was 5.59×10~4 Da.The ratio of monosaccharide content(arabinose∶xylose∶mannose∶glucose∶galactose)was 1∶1∶28∶8∶12,and the polysaccharide had certain ability to remove superoxide radical,hydroxyl radical and DPPH free radical in vitro,indicating better antioxidant activity.[Conclusion]The research can afford scientific foundation for the development and utilization of hawthorn resources and the pharmacological research on hawthorn polysaccharides.