
Boosting
Vitamin E in Corn and Other CropsBy David
Elstein October 9, 2003An Agricultural Research Service scientist and
cooperators are developing new varieties of corn and other food crops that have
higher levels of vitamin E. Twenty-five percent of Americans do not get enough vitamin E. It is
particularly important for pregnant women, and some researchers have shown that
it can decrease the risk of heart disease. The research was done by molecular biologist Edgar B. Cahoon of the
ARS Plant
Genetics Research Unit at the
Donald Danforth Plant Science
Center in St. Louis, along with his former colleagues at DuPont Crop
Genetics, Wilmington, Del. The scientists used genes found in rice, barley and
wheat, each of which contains high levels of vitamin E. Now that their three years of research have led to a safe, healthful variety
of corn, Cahoon and his colleagues are working on similar studies with
soybeans. He believes many other crops would benefit from the new approach. Vitamin E is a generic name for naturally occurring compounds called
tocotrienols and tocopherols. Cahoon looked at the pathway that leads to
tocotrienols, something that had not been studied much. The scientists were
able to isolate a gene for the enzyme homogentisic acid geranylgeranyl
transferase. This enzyme is responsible for producing a tocotrienol form of
vitamin E in cereal grains. When the gene was added to corn plants, the
kernels' vitamin E content increased sixfold. In addition to making the crop more nutritious, boosting vitamin E levels is
likely to increase the crop's shelf life. Vitamin E occurs naturally in
vegetable oils, nuts and green leafy vegetables. The research was reported in the September issue of Nature Biotechnology. ARS is the U.S. Department of
Agriculture's chief scientific research agency. U.S. Department of Agriculture |