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

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 D101and 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.