Abstract:

The in vivo and in vitro antioxidant properties of flavonoids extracted with ethanol from the dry leaves of
Phragmites communis Trin. (PCF) were studied by measuring the effects on hemolysis of rat red blood cells (RBCs) and
MDA generation in liver homogenate and mitochondria in vitro. Results indicated that PCF in the concentration range of
0.5–10 mg/mL could inhibit the hemolysis of rat RBCs and the generation of MDA in rat liver homogenate and mitochondria
in a dose-dependent manner, suggesting obvious antioxidant activity in vitro. Increased concentrations of PCF could enhance
the activities of GSH-Px and SOD and reduce MDA levels in the serum of S180 tumor-bearing mice so as to have elevated
antioxidant activity. PCF at the dose of 300 mg/(kg·d) had antioxidant activity comparable to that of 5-FU at 10 mL/(kg·d)
for tumor-bearing mice in vivo.

Key words: Phragmites communis Trin. leaves, flavonoids, antioxidant activity, in vivo and in vitro