密蒙花黄酮的纯化及抗氧化活性研究

摘要

为考察密蒙花黄酮纯化工艺参数,并评估密蒙花黄酮的抗氧化活性.以总黄酮含量为指标,采用大孔吸附树脂法对密蒙花黄酮进行纯化,考察5种不同类型大孔吸附树脂对密蒙花黄酮的动态吸附及解吸附能力,筛选出最佳树脂类型和纯化工艺,以1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picryl-hydrazyl,DPPH)自由基清除活性等4种抗氧化指标评价密蒙花抗氧化活性并与黄酮含量进行相关分析.筛选出X-5型树脂,并确定最佳纯化工艺为:样品上样质量浓度6.00 mg/mL,上样流速2 BV/h,上样量20 BV,解吸附流速1.5 BV/h,解吸附剂用量2 BV,80 %乙醇解吸附效果最好.密蒙花粗提物经纯化后,其总黄酮、毛蕊糖苷和蒙花苷含量分别提高2.28倍、2.72倍和2.00倍,纯化后密蒙花抗氧化活性显著增强,且与黄酮含量之间存在显著相关性.筛选出大孔树脂法纯化密蒙花黄酮的最佳条件,黄酮对密蒙花抗氧化活性具有显著作用.%In order to explore the purification process parameters of flavonoids and evaluate the antioxidant property of the Buddlejae flos. The content of the total flavonoids was used as the determination index, the macroporous adsorption resin was used to purify the flavonoids.Taking the five types of macroporous adsorption resin of the dynamic adsorption and desorption capacity of the total flavonoids as the indexes,the best sorbent and purification parameters of the total flavonoids was chosen. 1,1-diphenyl-2-picryl-hydrazyl(DPPH) radical scavenging activity and the other three antioxidant indices were used to evaluate the antioxidant activity of the Buddlejae flos. The correlation between antioxidant ability and the content of the total flavonoids was analysized. X-5 was the best sorbent and the optimal purification parameters were as follows: sample concentration was 6.00 mg/mL; loading rate was 2 BV/h;sampling amount was 20 BV;eluent flow rate was 1.5 BV/h; eluent volume was 2 BV; and the optimal desorption solvent was 80 % ethanol. The contents of buddleoside and acteoside were determined by high performance liquid chromatography(HPLC). After purification,the contents of the total flavonoids,buddleoside and acteoside were increased by 2.28,2.72 and 2.00 times respectively. Results indicated the crude extract of Buddlejae flos has strong antioxidant ability, which is further enhanced after purification. The antioxidant ability of Buddlejae flos was correlated with the total flavonoids content significantly. The optimal parameters of dynamic adsorption and desorption for flavonoids purification of the Buddlejae flos were obtained.The total flavonoids played the important role for the antioxidant activity of the Buddlejae flos.