Cancer Fighting Punch Added to Tomato

California Farmer Magazine Compiled by staff Cancer-Fighting Punch Added to Tomato

Forget the attack of the killer tomato, this is the attack of the healthy tomato: A team of scientists has developed a tomato that contains as much as three and a half time more of the cancer-fighting antioxidant lycopene. It turns out that the antioxidant-rich tomato was a happy accident.

Scientists at Purdue University and the U.S. Department of Agriculture’s Agricultural Research Service were working to develop tomatoes for food processing that were of higher quality and would ripen later.

They accomplished that, but in the process they discovered that the new tomatoes also had significantly more of the antioxidant than conventional tomatoes.

“We were quite pleasantly surprised to find the increase in lycopene,” says Avtar Handa (pronounced “Honda”), professor of horticulture at Purdue.

Although increasing the nutritional value of foods is the goal of so-called second-generation biotechnology products, there have been few success stories.

“This is one of the first examples of increasing the nutritional value of food through biotechnology,” Handa says. “In fact, it may be the first example of using biotechnology to increase the nutritional value of a fruit.”

Codiscoverer Autar Mattoo, who heads the USDA Vegetable Laboratory, says the increase in lycopene occurred naturally in the genetically modified tomatoes. “The pattern for the accumulation was the same as in the control tomatoes,” he says. “The lycopene levels increased two to 3.5 times compared to the non-engineered tomatoes.”

The research was announced in the June issue of Nature Biotechnology. A separate article on the research in Nature Biotechnology noted, “The findings … remind us that in the ‘rational’ and quantitatively driven post-genomic era, serendipity still has a large part to play.”

A U.S. patent application has been filed on behalf of the joint owners USDA and the Purdue Research Foundation. The Consortium for Plant Biotechnology Research Inc., a USDA funded program, funded the research.

Lycopene is a pigment that gives tomatoes their characteristic red color. It is one of hundreds of carotenoids that color fruits and vegetables red, orange or yellow. Of these pigments, the most familiar is the beta-carotene, which is found in carrots.

To develop the lycopene-rich tomato, the researchers inserted a gene, derived from yeast, fused to a promoter gene into tomato plants. The promoter gene helps turn on the yeast gene in the tomato.

“The promoter gene is like a ZIP code that tells the yeast gene when and where to turn on in tomato,” Handa says. “For high-lycopene tomatoes we used a promoter that targeted expression of the introduced gene in fruits only.”