Tomatoes genetically modified
to be rich in antioxidants called anthocyanins appeared to extend the life
spans of cancer-prone mice, according to a study reported via letter in Nature Biotechnology.
The modified tomatoes were created by adding two genes (Delila and
Rosea1) from the snapdragon flower. The anthocyanins, which belong to the
flavonoid class of antioxidants, gave the tomatoes a peculiar purple
The two genes that were isolated are responsible for flower pigmentation
and, when introduced in other plants, turned out to be the perfect
combination to produce anthocyanins, the same phytochemical found in
blueberries. Anthocyanin is thought to have anti-cancer properties.
Chemical tests revealed that the purple tomato has a very high
antioxidant activity, almost tripled in comparison to the natural fruit,
making it very useful to study the effect of anthocyanins.
The researchers fed a powder obtained from the purple tomatoes to mice
that lacked the p53 gene, which helps protect against cancer. These mice
had an average life span of 182 days compared to 142 days for
p53-deficient mice fed a standard diet.
The significance of these findings?
According to one of the researchers quoted by the BBC:
"Most people do not eat five portions of fruits and vegetables a day,
but they can get more benefit from those they do eat if common fruit
and veg can be developed that are higher in bioactive compounds."