大孔树脂纯化白及多酚及其体外抗氧化活性研究

Purification of Bletilla striata Polyphenols by Macroporous Resin and Its Antioxidant Activities in Vitro

对比了10种大孔树脂对白及多酚粗提液的静态吸附与解吸效果,并对优选的LSA-21树脂纯化白及多酚粗提液的工艺进行了探讨,对纯化前后的白及多酚提取液的体外抗氧化活性进行检测。研究结果表明:室温下,多酚粗提液质量浓度0.4~0.6 g/L,pH值4,上样流速 2.0 mL/min为LSA-21树脂吸附白及多酚粗提液的最佳工艺;乙醇体积分数80%,解吸液pH值6,上样流速1.0 mL/min为最佳解吸工艺。以100 mL质量浓度为0.47 g/L粗提液在最佳工艺条件下纯化,白及多酚纯度由4.48%提高到 27.61%,纯化效果较好。纯化后的白及多酚清除自由基能力有显著提升,其对DPPH自由基、羟基自由基和超氧阴离子自由基的半数抑制浓度(IC 50 )分别为7.72、8.65和205.39 mg/L。

The static adsorption and desorption effects of ten kinds of macroporous resins on B. striata polyphenols crude extract were compared, and the optimal process of purifying with LSA-21 resin was discussed. Furthermore, the antioxidant activities of the pre- and post-purification B. striata polyphenols were tested in vitro . The results showed that, at room temperature, the optimal process parameters for adsorption of crude extract with LSA-21 resin were as follows: the mass concentration of polyphenol crude extract 0.4-0.6 g/L, pH vlaue 4, and the loading velocity 2.0 mL/min. The optimal process parameters for desorption were as follows: desorption solution ethanol volume fraction 80%, pH vlaue 6, and elution flow rate 1.0 mL/min. The purity increased from 4.48% to 27.61% after purifying 100 mL of 0.47g/L crude extract under the optimal technological conditions, and the purification effect was good. The DPPH · scavenging activity of the purified B. striata polyphenols was obviously improved. The IC 50 of DPPH ·、OH · and O - 2 · free radicals were 7.72, 8.65 and 205.39 mg/L respectively.