The findings appear in the Feb. 26 print edition of the Journal of Agricultural and Food Chemistry, a peer-reviewed journal of the American Chemical Society, the world's largest scientific society. The article was initially published Jan. 25 on the journal's Web site.
Flavonoids are phenolic compounds that have potent antioxidant activity. Many are produced in plants in response to environmental stressors, such as insects or competing plants.
"If an aphid is nibbling on a leaf, the plant produces phenolics to defend itself," says Alyson Mitchell, Ph.D., a food scientist at the University of California, Davis, and lead author of the paper. "Bitter or harsh phenolics guard the plant against these pests."
The need for these natural safeguards decreases with the use of herbicides and pesticides in conventional agriculture. This decrease is reflected in the total amount of antioxidants the plants produce. "This helps explain why the level of antioxidants is so much higher in organically grown food," Mitchell says. "By synthetically protecting the produce from these pests, we decrease their need to produce antioxidants. It suggests that maybe we are doing something to our food inadvertently."
Mitchell measured antioxidants found in corn, strawberries and a type of blackberry called a marionberry. "We started with these three due to plant availability," Mitchell explains, "but we intend to widen our search to include tomatoes, peppers, broccoli and a variety of othe
Contact: Allison Byrum
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