T. MADHUJITH1, A. K. Muhammad1, C.-T. Ho2, and F. Shahidi1. (1) Dept. of Biochemistry, Memorial Univ. of Newfoundland, 300 Prince Phillip Dr., Saint John's, NF A1B 3X9, Canada, (2) Dept. of Food Science, Rutgers, The State Univ. of New Jersey, 65 Dudley Rd., New Brunswick, NJ 08901-8520
Epidemiological studies have shown that consumption of fruits and vegetables may reduce the risk of several forms of cardiovascular diseases and cancer by providing enhanced antioxidant protection in the human body. Recent interest in possible protective effects of dietary antioxidants has prompted investigations of different plant foods, including blueberries. Canada and the United States supply about 95% of blueberries used by food industry and this emphasizes for us the significance of investigating the health effects of the fruit.
The objective of this study was to examine twelve farmed and wild blueberry cultivars grown in six different locations of three provinces of Canada for their antioxidant properties.
Blueberry fruits were extracted with water and centrifuged to remove the cellular debris. The extracts so obtained were analyzed for their total phenolic content. Antioxidative activity of the extracts was quantified by Trolox equivalent antioxidative capacity (TEAC), oxygen radical absorbance capacity (ORAC) and a chemoluminescence technique using Photochem®.
The total phenolic content showed a strong relationship (r=0.84) with the antioxidant activity as measured by Photochem®. Total phenloic content varied from 84 to 278 mg/g of fresh fruit while TEAC values ranged from 1.07 to 1.34. The ORAC values ranged from 14.31 to 15.18 µmol of Trolox equivalents/gram fresh fruit. The highest inhibition (75%) was exhibited by farmed blueberries grown in Newfoundland while the lowest (36%) was exhibited by wild blueberries from Quebec. The results showed that the antioxidant capacity depended on the cultivar and the location where they were grown.
Session 33F, Nutraceuticals & Functional Foods: Antioxidants and phytochemical analysis