Comparative Polyphenolic Content and Antioxidant Activities of Some Wild and Cultivated Blueberries from Romania

Abstract

Two wild and three cultivated blueberry varieties (‘Elliot’, ‘Bluecrop’ and ‘Duke’) from Romania were analyzed comparatively in order to determine the total polyphenols, total anthocyanins, total flavonoids content and measuring the antioxidant activity using three different single electron transfer-based assays, Trolox equivalent antioxidant capacity (ABTS), ferric reducing ability (FRAP), 2,2-diphenylpicrylhydrazil radical scavenging capacity (DPPH) and one hydrogen atom transfer-assay, oxygen radical absorbance capacity (ORAC). Total polyphenols content ranged from 424.84 - 819.12 mg GAE/100 g FW, total flavonoids ranged from 84.33-112.5 mg QE /100 g FW and total anthocyanins ranged from 100.58-300.02 C3GE/100g FW. The anthocyanins were separated and quantified using RP-HPLC-DAD. In Vaccinium myrtillus, petunidin-3-glucoside and delphinidin-3-glucoside have the highest contribution to the anthocyanin content while in Vaccinium corymbosum, peonidin-3-galactoside represent the major anthocyanin. Except for ORAC assay (r=0.765), all antioxidant activity values obtained were highly correlated with total polyphenol content (0.923≤ r ≤0.986). Wild blueberries had higher total polyphenols content and also antioxidant activity compared with cultivated ones.