厚朴花低聚糖、多糖的分离纯化及其体外抗氧化活性研究

Study on the Separation and Purification of Oligosaccharide and Polysaccharide from the Flowers of Magnolia officinalis and Their in vitro Antioxidant Activity

目的：从厚朴花中分离、纯化其低聚糖、多糖组分并考察其体外抗氧化活性。方法：取厚朴花先以80%乙醇为提取溶剂,采用回流提取法及柱色谱分段纯化得到厚朴花低聚糖组分;再以厚朴花低聚糖提取后的药渣为原料,用热水回流提取法及分段纯化得到厚朴花多糖组分。以2,6-二叔丁基-4-甲基苯酚（BHT）为阳性对照,通过1,1-二苯基-2-三硝基苯肼（DPPH）自由基清除率、还原能力、总抗氧化能力试验考察不同质量浓度（0.1、0.2、0.4、0.6、0.8、1.0、1.2 mg/ml）厚朴花低聚糖及多糖组分的体外抗氧化活性。结果：厚朴花的低聚糖、多糖组分在质量浓度为0.1~1.0 mg/ml时其DPPH自由基清除作用、还原能力和总抗氧化能力均随质量浓度的增加而增强;且在3个试验中,低聚糖组分分别在0.8~1.0、0.2~1.0、0.1~1.0 mg/ml时各抗氧化指标与BHT相当（P〉0.05）;各试验中低聚糖组分的指标数据略高于多糖组分,但二者间比较多数指标差异无统计学意义（P〉0.05）。结论：厚朴花中的低聚糖和多糖组分均具有较强的体外抗氧化活性,低聚糖组分的体外抗氧化活性略优于多糖组分。

OBJECTIVE：To separate and purify oligosaccharide and polysaccharide from the flowers of Magnolia officinalis,and to investigate their in vitro antioxidant capacity.METHODS：Using 80% ethanol as extraction solvent,the flowers of M.officinalis were extracted by reflux extraction and purified by column chromatogram to obtain oligosaccharide.The dregs of oligosaccharide extraction was used as raw material,and were extracted by hot water reflux extraction and purified by segmentation purification to obtain polysaccharide.Using 2,6-di-tert-butyl-4-methylphenol（BHT）as positive control,in vitro antioxidant capacity of different concentrations of oligosaccharide and polysaccharide from the flowers of M.officinalis（0.1,0.2,0.4,0.6,0.8,1.0,1.2mg/ml）were investigated through clearance rate test,reducing capacity test,total antioxidant activity test of 1,1-diphenyl-2-trinitrophenylhydrazine（DPPH） free radical.RESULTS：DPPH free radical clearance,reducing capacity and total antioxidant activity were enhanced as the increase of oligosaccharide and polysaccharide concentration,when the concentration of oligosaccharide and polysaccharide ranged 0.1-1.0 mg/ml.In 3 tests,antioxidant activity index of oligosaccharide were similar to those of BHT（P〉0.05）when the concentrations were 0.8-1.0,0.2-1.0,0.1-1.0 mg/ml.In 3 tests,most of antioxidant activity index of oligosaccharide were slightly higher than those of polysaccharide,without statistical significance（P〉0.05）.CONCLUSIONS：The oligosaccharide and polysaccharide from the flowers of M.officinalis show good in vitro antioxidant capacity,and in vitro antioxidant capacity of oligosaccharide is better than that of polysaccharide.