Objective: To evaluate the total antioxidant activity of extracts from Polygonum lapathifolium in vitro. Method: 1

1-diphenyl-2-picryl-2-picrylhydrazyl (DPPH) radical scavenging

diammonium salt (ABTS) radical scavenging

and ferric reducing antioxidant power (FRAP) assay were used to analyze the antioxidant activity. Result: Compared with 6-hydroxy-2

5

7

8-tetramethylchroman-2-carboxylic acid (Trolox) and positive control propyl gallate (PG)

butylated hydroxyanisole (BHA) and 2

6-di-tert-butyl-4-methylphenol (BHT)

the ethyl acetate extract and the methanol extract showed higher scavenging activity against DPPH radical

ABTS radical

and reducing antioxidant power of TPTZ than that of BHT

lower than that of PG and BHA. Conclusion: P. lapathifolium exhibited the good total antioxidant activity. In three extracts of P. lapathifolium

the ethyl acetate extract showed higher total antioxidant activity than that of the methanol extract

and the petroleum ether extract hardly had antioxidant activity.