Antioxidant Activity of Ethanol Extracts of Different Buckwheat

The total phenolics and flavonoids and antioxidant capacities along with hydroxyl radical scavenging ability of common buckwheat and tartary buckwheat ethanol extracts in different development stage were examined.The results showed that the total phenolic and the flavonoids contents of common and tartary buckwheat unfolded a similar tendency in their whole growth time,both of which rose then declined and both achieved highest figures in the full-blossoming stage.The contents of the total phenolic and flavonoids of tartary buckwheat was higher than that of common buckwheat and all extracts exhibited good antioxidant activity.In the case of tartary buckwheat,its total antioxidant capacity and hydroxyl radical scavenging ability achieved(57.1%) highest in the full-blossoming stage.Significant and positive linear correlations were found between antioxidant capacities and phenolic contents(R2 0.90),indicated that phenolics were the dominant antioxidant constituents in the buckwheat.