Purple Tomatoes Rich in Anthocyanins

Researchers from the UK, Italy, Germany and the Netherlands have used snapdragon genes to grow purple tomatoes that are high in anthocyanin flavonoids, a class of pigments produced by higher plants, reports Cordis News. The new tomatoes could offer increased protection against a range of diseases, including cancer and cardiovascular disease.

The team, led by Professor Cathie Martin of the John Innes Centre in the UK, found that by expressing genes that make snapdragon flowers produce anthocyanins, the anthocyanin levels in the tomatoes was increased threefold. That brings the concentration up to the levels seen in blackberries and blueberries, a substantial improvement over previous efforts to engineer high-anthocyanin tomatoes. Also, the new tomatoes took on a rich, purple color.

Cancer-susceptible mice that were fed a diet supplemented with the high-anthocyanin tomatoes lived significantly longer than those fed with conventional red tomatoes. “This is one of the first examples of metabolic engineering that offers the potential to promote health through diet by reducing the impact of chronic disease,” says Martin. “And [it’s] certainly the first example of a genetically modified organism with a trait that really offers a potential benefit for all consumers. The next step will be to take the preclinical data forward to human studies with volunteers to see if we can promote health through dietary preventive medicine strategies.”

The research, funded under the EU's Fifth and Sixth Framework Programmes (FP5 and FP6), focused on flavonoids and their contribution to improving health through diet. It was published online in the journal Nature Biotechnology in October.

See www.nature.com for more details.