Antioxidant capacity and flavonoid contents in wild strawberries

Authors: Wang, Shiow; Lewers, Kimberly

Submitted to: Journal American Society Hortscience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/2/2007
Publication Date: 9/1/2007
Citation: Wang, S.Y., Lewers, K.S. 2007. Antioxidant capacity and flavonoid contents in wild strawberries. Journal American Society Hortscience. 132(5):629-637.

Interpretive Summary: Strawberries are a good source of natural antioxidants which play an important role in protecting human health. Wild strawberry species are valued by breeders as sources of novel traits, especially pest resistance and stress tolerance. However, wild strawberry has not been evaluated for their fruit quality or antioxidant capacity. We conducted experiments to evaluate the antioxidant content and antioxidant activities in wild strawberry species, to determine which compounds were closely correlated with antioxidant activity and also to identify the wild strawberry genotypes possessing high antioxidant activity for use in cultivar development. We found that some wild strawberries have high levels of antioxidants, and good fruit quality. Several wild accessions of strawberry were identified for breeders so that they can use the desirable fruit traits from the wild strawberries and still keep antioxidant levels high. Information obtained from this research is useful for other scientists, strawberry growers and consumers interested in antioxidant compounds and in improving human health.

Technical Abstract: Fruit of the cultivated strawberry are a good source of natural antioxidants which play an important role in protecting human health, though antioxidant levels vary considerably among strawberry genotypes. The cultivated strawberry is a hybrid of two very different wild progenitor species: F. virginiana Mill. and F. chiloensis (L.) Mill. Accessions of the progenitor species are valued by strawberry breeders as sources of novel traits but have not been evaluated for antioxidant capacity or levels of antioxidant compounds. Fruit of a total of 19 accessions from each of the three species, cultivated strawberry plus the two progenitor species (F. ×ananassa, F. virginiana and F. chiloensis), were evaluated for levels of antioxidant capacity, total phenolics, total anthocyanins, and flavonoid content. At the species level, F. virginiana fruit had significantly higher (p = 0.05) antioxidant capacity, total phenolics, and total anthocyanins than did the F. chiloensis and F. ×ananassa fruit. Antioxidant capacity was significantly correlated with total phenolics and the total anthocyanin component of total phenolics, but was not significantly correlated with any of the individual compounds, including the predominant anthocyanin, pelargonidin 3-glucoside. Individual wild progenitor accessions that were higher in antioxidant capacity, total phenolics and total anthocyanins than the top-ranking F. ×ananassa accession tested were all F. virginianna accessions: NC 95-19-1, JP 95-1-1, CFRA 0982, NC 96-5-3, and RH 30 fruit were highest in antioxidant capacity and should prove useful towards development of strawberry cultivars with high antioxidant capacities.