Levels of phenolic compounds and their effects on antioxidant capacity of wild Vaccinium arctostaphylos L. (Qare-Qat) collected from different regions of Iran

Antioxidant activities in the leaves and fruits of wild Vaccinium arctostaphylos (locally named Qare-Qat) from different regions of Iran were evaluated using the stable 1, 1-diphenyl-2-picrylhydrazyl free radical and ferric reducing/antioxidant power methods. Variations in antioxidant activity, total phenolic, anthocyanin, and flavonoid content in fruit samples among genotypes was much greater than the variation observed between growing seasons, indicating that genetics plays a more important role than growing season in V. arctostaphylos fruits. The data indicated that the fruits of the Kelardasht genotype had the highest total phenolic content [42.73 ± 1.5 mg gallic acid equivalents (GAE) g^-1 DW], anthocyanin content (1.00 ± 76 mg g^-1), and antioxidant activity while the Masouleh genotype had the lowest antioxidant activity. Significant main effects for genotype, growing season, and genotype × growing season were observed for anthocyanin and antioxidant activity, while variation in polyphenolic content indicated that genotype plays more of a role than growing season in the leaves of V. arctostaphylos. Correlation analyses indicated that there was a linear relationship between antioxidant activity and the total phenolic and anthocyanin content in fruits and leaves. Over both growing seasons the flavonoids did not play an important role in the antioxidant potential of the leaves.