The antioxidant effects of aqueous and organic extracts of Panax quinquefolium, Panax notoginseng, Codonopsis pilosula, Pseudostellaria heterophylla and Glehnia littoralis.

The roots of Panax quinquefolium, Panax notoginseng, Glehnia littoralis, Codonopsis pilosula and Pseudostellaria heterophylla were extracted with an aqueous extraction method and also with an organic extraction method. The aqueous extracts of Glehnia littoralis and Codonopsis pilosula were the most potent in inhibiting erythrocyte hemolysis. The aqueous extracts of Panax quinquefolium and Panax notoginseng had lower potencies while the aqueous extract of Pseudostellaria heterophylla and the organic extract of Panax quinquefolium were only weakly active. The organic extracts of Glehnia littoralis, Panax heterophylla and Panax quinquefolium were potent in inhibiting lipid peroxidation while the organic extracts of Codonopsis pilosula and Panax notoginseng had weaker potencies. The aqueous extracts possessed much lower potencies the corresponding organic extracts. However, the Glehnia littoralis extract was the most potent aqueous extract. The results suggest that Glehnia littoralis, Codonopsis pilosula, Panax notoginseng and Panax heterophylla are cheaper substitutes of Panax quinquefolium with regard to antioxidant activity.