厚朴花低聚糖、多糖的分离纯化及其体外抗氧化活性研究

摘要

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. offici-nalis were extracted by reflux extraction and purified by column chromatogram to obtain oligosaccharide. The dregs of oligosaccha-ride extraction was used as raw material,and were extracted by hot water reflux extraction and purified by segmentation purifica-tion to obtain polysaccharide. Using 2,6-di-tert-butyl-4-methylphenol(BHT)as positive control,in vitro antioxidant capacity of dif-ferent concentrations of oligosaccharide and polysaccharide from the flowers of M. officinalis (0.1,0.2,0.4,0.6,0.8,1.0,1.2 mg/ml)were investigated through clearance rate test,reducing capacity test,total antioxidant activity test of 1,1-diphenyl-2-trinitro-phenylhydrazine (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 oligosaccha-ride were slightly higher than those of polysaccharide,without statistical significance (P>0.05). CONCLUSIONS:The oligosac-charide and polysaccharide from the flowers of M. officinalis show good in vitro antioxidant capacity,and in vitro antioxidant capac-ity of oligosaccharide is better than that of polysaccharide.