Rice grains with less phytic acid could mean improved nutrition for the world's malnourished, more nutritious animal feed and less potential for water pollution from manure, reports the US Agricultural Research Service (ARS) this week.
The human body rarely lacks phosphorus, but people in developing nations with primarily grain-based diets sometimes have mineral deficiencies, reports ARS. Cereals like rice store most phosphorus in the grain as phytic acid, which can not be digested by one-stomached animals like fish, chickens, pigs and humans. It binds to minerals such as iron, calcium, magnesium and zinc in the slightly acidic conditions in the intestines. Because phytic acid is poorly digested and utilised, these bound minerals are less available in the body. It can also lead to environmental problems because undigested phosphorus expelled in manure can pollute lakes and streams.
J. Neil Rutger, director and supervisory research geneticist at the Dale Bumpers National Rice Center in Stuttgart, Arkansas, has bred a new stock, what scientists call germplasm, for creating improved varieties with less phytic acid. He worked with research geneticist Victor Raboy, renowned for a patented technique that yielded lines of corn, barley and soybean with lower amounts of phytic acid, commonly known as phytate. Raboy is with the Small Grains and Potato Germplasm Research Unit in Aberdeen, Idaho.
This is the first time Raboy's technique was used to produce low-phytate rice. This rice has only half the phytic acid content of its parent and an increased amount of more easily digested phosphorus.
The Agricultural Research Service, the US Department of Agriculture's chief scientific research agency, and the University of Arkansas released the new rice to breeders and researchers earlier this year.
Rutger and research chemist Rolfe J. Bryant analysed the new line and other varieties. Bryant found that the total phytic acid concentration in the brown rice (with outer bran layer intact) of the new line was 49 per cent lower than that of its parent - a characteristic improved through breeding.
Full findings on the research were published in the September 2002 issue of Agricultural Research magazine.