Researchers from Cornell University, Ithaca, NY, have placed blueberries atop a short list of foods in terms of antioxidant activity. The test employed is called the cellular antioxidant activity (CAA) assay, which measures the bioactivity inside cells. The results of this research were published in the Oct. 31 issue of the Journal of Agricultural and Food Chemistry.
The Cornell researchers used the CAA assay to determine how antioxidants react with cells. The antioxidant activities of selected phytochemicals and fruit extracts, including those from in wild blueberries, cranberries, apples, and red and green grapes, were evaluated using the assay. They note that among the fruits tested, blueberry had the highest CAA value, followed by cranberry, apple and red grapes, and green grapes. The researchers note that “the CAA assay is a more biologically relevant method than the popular chemistry antioxidant activity assays because it accounts for some aspects of uptake, metabolism, and location of antioxidant compounds within cells.”
Rui Hai Liu, Ph.D., associate professor, Department of Food Science, Cornell University, and lead author of the study, notes that oxygen radical absorbance capacity (ORAC) tests are still valuable, but that the CAA assay helps advance antioxidant research to “see how these compounds react with cells. We believe this is a stronger measure of how antioxidant compounds could potentially react in the body.”
