Abstract: In this study,the water-extraction and ethanol precipitation was used to extract polysaccharides from Platycodon grandiflorum. The anti-fatigue effects and effective doses of P.grandiflorum polysaccharide on mice were analyzed using Panax quinquefolius as positive control,distilled water as blank control.Three concentrations of P.grandiflorum polysaccharide (0.2 mg/mL,0.5 mg/mL and 0.8 mg/mL) were applied to mice.After 21 days’ treatment,the loaded swimming time,blood urea nitrogen，hepatic glycogen and blood lactate of mice were determined.The results indicated that P.grandiflorum polysaccharide obviously prolonged the loaded swimming time,reduced blood urea nitrogen and blood lactate,increased hepatic glycogen (P<0.01) of mice.The 3 cocentration groups of P.grandiflorum polysaccharide can improve the anti-fatigue ability of mice effectively,and the 0.8 mg/mL of P.grandiflorum polysaccharide group showed the highest activity.

Key words: Platycodon grandiflorum polysaccharide, mice, anti-fatigue