Bioactive compounds and antioxidant activity of highbush blueberry ( Vaccinium corymbosum ) grown in southern Spain

To study whether the content of bioactive compounds and antioxidant activity depends on the variety of blueberries grown, the content of flavonoids, resveratrol, total tannins and vitamin C of 4 varieties grown in southern Spain (Huelva) have been analyzed. After the analyses carried out, it can be verified that all the compounds identified, as well as the antioxidant activity, present significant differences between the varieties under study. Millennia was the variety with the highest concentration of monomeric anthocyanins, which showed more than double of concentration of Star variety. However, the latter had the highest concentration of flavan-3-ol derivatives. Only a flavonol could be identified in Millennia and Star varieties. Jewel was the variety with the highest resveratrol content, while Windsor had the highest concentration in total tannins and the best antioxidant activity values. A multivariate principal component analysis showed that the varieties can be differentiated mainly by their composition in flavonoid compounds. Finally, a multiple regression analysis showed that bioactive compounds influence antioxidant activity jointly and not individually