Scientists design 'anti-cancer' tomato

The lycopene-rich tomato (image: Peggy Greb, USDA)

A tomato has been engineered to contain higher levels of a chemical which may offer protection against cancer.

The tomato was developed at Purdue University in Indiana, US, by accident as scientists hunted higher quality strains that would ripen later.

Tomatoes, even in their processed form, are already considered to be beneficial to health.

This is because they contain various antioxidant chemicals which may be able to prevent cell damage in the body.

One of these chemicals is called lycopene, the pigment which gives the fruit its traditional red colour.

It has long been associated with good health - a study of thousands of men found that eating 10 or more servings of tomato sauce or tomatoes a week reduced prostate cancer risk by 45%.

Boosted

The new tomato strain developed at Purdue contains on average between two and three and a half times the lycopene of the average tomato.

When you just take lycopene as a drug it doesn't have the same effect

Randy Woodson, Purdue University

Other research has found that lycopene may be able to reduce the amount of so-called "bad" cholesterol, and if so, perhaps the risk of heart disease.

Researcher Avtar Handa said: "We were quite pleasantly surprised to find the increase in lycopene.

"The pattern for the accumulation was the same as in the control tomatoes.

Yeast gene

"We are excited about this approach, not only because it results in an increase in lycopene in tomato, but because we think it could be used to increase the phytonutrient content of other fruits and vegetables."

Randy Woodson, another Purdue expert, said: "When you just take lycopene as a drug it doesn't have the same effect.

"There is still a lot of biology to understand before we know why phytonutrients in food are so much more effective than if they are given as supplements."

To develop the lycopene-rich tomato, a researcher inserted a yeast-derived gene into tomato plants.

This gene affects the product of chemicals which help build compounds such as lycopene.

The inserted yeast gene was coupled to another gene which instructed it to work only in the fruits.

This is not the first GM project which has boosted the nutrient content of the tomato.

Other projects have boosted other tomato antioxidants such as flavonols and beta-carotene.