IRRI, LOS BAÑOS, Laguna — Researchers at Ghent University in Belgium have succeeded in stabilizing folates in biofortified rice, which can offer a solution to serious health problems caused by folate deficiency in developing countries.
The human body is unable to make vitamin B9 or folate. To remain healthy, adults need approximately 400 micrograms of folates per day while pregnant women, 600 micrograms, on a daily basis.Folates are abundant in green leafy vegetables (folium is Latin for leaf), such as spinach and legumes (e.g. beans). Most staple crops, such as rice and other cereals, contain very low amounts of this vitamin.
Inadequate folate intake can have severe effects on human health. In addition to certain forms of anemia, folate deficiency in pregnant women can result in an impaired development of the neural tube (the precursor of the spinal cord) of the embryo. These developmental problems often result in spina bifida or the so-called “cleft spine”.
Folate deficiency is also associated with Alzheimer disease, cardio-vascular diseases and the development of a range of cancers. Due to the marginal levels of folate in rice, consumed by about half the world population as the sole energy source, folate deficiency is highly prevalent in developing countries. Several studies show that in certain regions, like China and India, the occurrence of neural tube defects is at least 10-fold higher than those in Western countries.
In 2007, a research team from Ghent University, coordinated by Professor Dominique Van Der Straeten, reported the development of a first generation of rice lines with 100-fold higher folate levels as compared to normal rice. This result was achieved through metabolic engineering, the modulation of the biosynthesis pathway of a plant compound. The new study shows that about half of the folate content in these rice lines degrades after half a year.
Vitamins are unstable molecules that degrade easily upon contact with oxygen, light, humidity, increased temperatures and changes in acidity. Hence, it is important to consume food products, such as vegetables and fruit, as fresh as possible.
A lot of vitamins get lost, not only during food processing and preparation, but also during storage. Evidently, these problems occur in harvest products such as rice grains that are stored for a longer period. These stability problems become more severe in developing countries where the storage in high temperature and high humidity is inevitable.
To tackle this problem, researchers from the Ghent lab applied metabolic engineering to develop a new rice prototype in which the folate content remains stable upon long term storage. PNA