Effect of extraction conditions on antioxidant activity of barberry (Berberis vulgaris L.) fruit extracts

Barberry fruit is consumed in different forms including dried fruit, juice, jam and marmalade in Iran. This fruit is also used as a food additive (flavoring and colorant) in soup and rice dishes. In present study, antioxidant activities of acetone, ethanol and water (infusion and decoction) extracts of barberry (Berberis vulgaris) fruit were investigated using 2,2-azinobis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and reducing power methods. Total phenolic contents of the extracts were also estimated using Folin-Ciocalteu assay. In ABTS assay, acetone and ethanol extracts showed the highest radical scavenging activity, while in DPPH and reducing power methods, acetone extract and decoction exhibited the strongest antioxidant activity. Meanwhile, the antioxidant potential of water extracts increased with increasing heating time (antioxidant activity of decoction was higher than that of infusion). The highest total phenolic content was found in the acetone extract (92.75 mg GAE per g). It was concluded that the acetone extract and decoction of barberry fruit can be used as an effective natural antioxidant in food industry.