鸭跖草总黄酮的大孔树脂纯化工艺及抗氧化活性研究

Study on Total Flavonoids Purification by Macroporous Resin and Antioxidant Activity of Flavonoids in Commelinae Herba

目的研究鸭跖草总黄酮的大孔树脂纯化工艺及其抗氧化活性。方法以静态饱和吸附量和解析率为指标,对3种大孔树脂(D101,NKA-9,AB-8)进行筛选,并以回收率为指标,通过L9(34)正交表设计实验,确立纯化总黄酮的最佳条件;以VC为对照品,采用DPPH·法、邻苯三酚自氧化法和邻二氮菲法分别测定鸭跖草总黄酮对1,1-二苯基-2-苦肼基自由基(DPPH·)、超氧阴离子(O_2^-)和羟基自由基(·OH)的抗氧化活性。结果 AB-8纯化鸭跖草总黄酮效果最好。最佳纯化工艺:上样液质量浓度为1.482 mg·mL^(-1),淋洗pH为4,乙醇洗脱液体积分数为70%,洗脱流速为2 mL·min^(-1);鸭跖草总黄酮对3种自由基的清除效率与浓度呈正相关,清除DPPH·、O_2^-和·OH的半数抑制浓度(IC50)分别为0.017 0,0.005 5,1.932 7 mg·mL^(-1),对DPPH·和·OH的清除作用弱于Vc,而对O_2^-的清除作用强于Vc,其中鸭跖草对O_2^-的清除能力最强。结论大孔树脂纯化鸭跖草总黄酮的效果显著,鸭跖草黄酮类化合物具有较强的抗氧化活性,值得进一步开发。

OBJECTIVE To study the total flavonoids purification by macropnrous resin and antioxidant activity of flavonoids in Commelinae Herba.METHODS Three types of macroporous resins including D101,NKA-9 and AB-8 were used to purify flavonoids with static adsorption capacity and elution ratio as evaluation factors.The optimum purification conditions were investigated with L9（34） orthogonal experimental design.The antioxidant activity of the extract was tested by using methods of DPPH·,pyrogallol autoxidation and phenan throline with Vc as reference.RESULTS AB-8 resin was better than D101 and NKA-9 resin.After experimental study,optimal purification condition of total flavonoids from AB-8 resin were as follows： the concentration of sample was 1.482 mg·mL^（-1）,the washing pH value was 4,the flow rate of 70% ethanol was 2 mL·min^（-1）.Total flavonoids of Commelinae Herba had antioxidant capacity,with a dose effect relationship.The IC50 of antioxidant activity by DPPH·,pyrogallol autoxidation and phenan throline were 0.017 0,0.005 5,1.932 7 mg·mL^（-1） respectively.The scavenging effect of Commelinae Herba on DPPH· radical and hydroxyl radical was weaker than that of Vc,while the superoxide anion scavenging effect was stronger than that of Vc.Superoxide anion free radical scavenging capacity of Commelinae Herba was the strongest.CONCLUSION The macroporous resin showes significant effect on the purification of flavonoids from Commelinae Herba which has strong antioxid antactivity,and can be further developed.