大孔吸附树脂纯化黄芪茎总黄酮的工艺及其抗氧化性

PURIFICATION OF TOTAL FLAVONOIDS FROM ASTRAGALUS STEMS WITH MACROPOROUS RESIN AND THEIR ANTIOXIDANT ABILITY

考察了LX-36型大孔吸附树脂纯化黄芪茎总黄酮的工艺条件及其体外抗氧化性。以总黄酮的吸附率及解吸率为参考指标,采用单因素和正交试验法对黄芪茎总黄酮的纯化工艺进行优化;通过黄芪茎总黄酮样品液对DPPH·(二苯代苦味酰基自由基)、·OH(羟基自由基)的清除率来考察其体外抗氧化活性。结果表明,黄芪茎总黄酮的最佳纯化工艺条件为:样品液的生药质量浓度为0.06 g/m L,pH为3.5,样品液体积/树脂质量为15 m L/g。振荡吸附时间为3.0 h,洗脱剂为80%(体积分数)的乙醇溶液,振荡解吸时间为1 h,解吸液体积/树脂质量为25 m L/g,在此条件下,黄芪茎浸膏中总黄酮的含量由7.16%提高到13.55%;黄芪茎总黄酮样品液对DPPH·、·OH具有较强的清除能力,而且其清除活性随黄芪茎总黄酮样品液质量浓度的增加而增强。

The purification technology of total flavonoids （TFs） from Astragalus stems with LX-36 type macroporous resin and theirs antioxidant ability in vitro were investigated in this study. The purification process of TFs was optimized by single factor and orthogonal test while adsorption and desorption ratio as evaluation indexes. The antioxidant ability of TFs extraction solution in vitro were measured by DPPH. and .OH scavenging experiments. The results showed that the optimum purification conditions of TFs were as follows： the crude drug concentration of 0.06 g/mL; pH of sample solution of 3.5; solution volume to resin mass ratio of 15 mL/g; shaking adsorption time of 3.0 h; eluent of 80% ethanol solution （volume fraction）; eluent volume to resin mass ratio of 25 mL/g and shaking desorption time of 1.0 h, respectively. The purity of TFs from Astrogalus stems extracts could be enhanced from 7.16% to 13.55% under the optimal conditions. The TFs in Astragalus stems had strong scavenging activity on DPPH· and·OH, and the scavenging activity was increased with the increasing of TFs concentration in the extraction solution.