News & Emerging Research about Beans and Health
Compounds that
color fruits and
veggies may protect
against colon cancer
Press release from Eurekalert Website
Understanding the molecular structures of compounds that give certain fruits and
vegetables their rich colors may help researchers find even more powerful cancer fighters, a
new study suggests.
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.
The findings also bring scientists a step closer to figuring out what exactly gives fruits and
vegetables their cancer-fighting properties.
“These foods contain many compounds, and we’re just starting to figure out what they
are and which ones provide the best health benefits”, said Monica Giusti, the lead author of
the study and an assistant professor of food science at Ohio State University.
Giusti presented the findings, which represent the collaborative efforts of Giusti and her
colleagues, on August 19 at the national meeting of the American Chemical Society in
Boston.
Giusti and her colleagues found that in some cases, slight
alterations to the structure of anthocyanin molecules
made these compounds more potent anti-cancer agents.
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 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.
“All fruits and vegetables that are rich in anthocyanins have compounds that can slow down
the growth of colon cancer cells, whether in experiments in laboratory dishes or inside the
body,” Giusti said.
TAKE HOME MESSAGE
We know from previously published medical literature
that beans are rich in anthocyanins. However, processing of beans and other
legumes may lead to degradation of anthocyanins. We need to conduct studies
to assess the effects of canning, freezing, and other processing techniques on
anthocyanin composition and antioxidant activity prior to communicating health
benefits associated with anthocyanins in legume products.