Public Release: 19-Aug-2007
Evidence from laboratory experiments on rats and on human colon cancer cells also suggests that anthocyanins, the compounds that give color to most red, purple and blue fruits and vegetables appreciably slow the growth of colon cancer cells
In their studies on human colon cancer cells grown in laboratory dishes, the researchers tested the anti-cancer effects of anthocyanin-rich extracts from a variety of fruits and vegetables. They retrieved these anthocyanins from some relatively exotic fruits and other plants, including grapes, radishes, purple corn, chokeberries, bilberries, purple carrots and elderberries.
The plants were chosen due to their extremely deep colors, and therefore high anthocyanin content. Some of these plants are also used as a source of food coloring.
The researchers found that the amount of anthocyanin extract needed to reduce cancer cell growth by 50 percent varied among the plants. Extract derived from purple corn was the most potent, in that it took the least amount of this extract (14 micrograms per milliliter of cell growth solution) to cut cell numbers in half. Chokeberry and bilberry extracts were nearly as potent as purple corn. Radish extract proved the least potent, as it took nine times as much (131 µg/ml) of this compound to cut cell growth by 50 percent.
In additional laboratory studies, she and her colleagues found that anthocyanin pigments from radish and black carrots slowed the growth of cancer cells anywhere from 50 to 80 percent. But pigments from purple corn and chokeberries not only completely stopped the growth of cancer cells, but also killed roughly 20 percent of the cancer cells while having little effect on healthy cells
In fact, other researchers at Ohio State have found that black raspberries may help reduce the growth of esophageal and colon cancers tumors.
This work received support from a U.S. Department of Agriculture-National Research Initiative grant