Blueberries and blackberries grown
at various locations in Georgia
were collected and analyzed for flavonoids, total anthocyanins, total
polyphenols, and Trolox-equivalent antioxidant capacity (TEAC). Each sample was
analyzed for phenolic acids (gallic acid, p-hydroxybenzoic acid, caffeic
acid, ferulic acid, and ellagic acid) and flavonoids (catechin, epicatechin,
myricetin, quercetin, and kaempferol). A high-performance liquid
chromatographic (HPLC) method with photodiode array detection was used for analysis.
Compounds were analyzed as aglycons after acid hydrolysis with 1.2 M HCl.
Identification of each compound was based on retention time and UV spectra by
comparison with pure commercial standards. Phenolic acids ranged from 0.19 to
258.90 mg/100 g fresh weight (FW), and flavonoids ranged from 2.50 to 387.48
mg/100 g FW. Total polyphenols ranged from 261.95 to 929.62 mg/100 g FW, and
total anthocyanins ranged from 12.70 to 197.34 mg/100 g FW. TEAC values varied
from 8.11 to a maximum of 38.29 M/g FW. A linear relationship was observed
between TEAC values and total polyphenols or total anthocyanins. The data
indicate that blueberries and blackberries are rich sources of antioxidants.