Quality Protein Maize
Encyclopedia
Quality Protein Maize contains nearly twice as much usable protein
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

 as other maize
Maize
Maize known in many English-speaking countries as corn or mielie/mealie, is a grain domesticated by indigenous peoples in Mesoamerica in prehistoric times. The leafy stalk produces ears which contain seeds called kernels. Though technically a grain, maize kernels are used in cooking as a vegetable...

 (or corn) grown in the tropics
Tropics
The tropics is a region of the Earth surrounding the Equator. It is limited in latitude by the Tropic of Cancer in the northern hemisphere at approximately  N and the Tropic of Capricorn in the southern hemisphere at  S; these latitudes correspond to the axial tilt of the Earth...

 and yields 10% more grain than traditional varieties of maize. It was developed by Dr. Surinder Vasal and Dr. Evangelina Villegas
Evangelina Villegas
Evangelina Villegas is a Mexican cereal biochemist whose work with maize led to the development of high-quality protein maize . She and her colleague, Dr. Surinder Vasal, shared the 2000 World Food Prize for this achievement....

 at the International Maize and Wheat Improvement Center (CIMMYT) in the late 1990s. For their achievement, they won the 2000 World Food Prize
World Food Prize
The World Food Prize is an international award recognizing the achievements of individuals who have advanced human development by improving the quality, quantity or availability of food in the world.-The Prize:...

.

The need for high-protein maize

In Central
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...

 and South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

, Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...

, and Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...

, several hundred million people rely on maize as their principal daily food, for weaning babies, and for feeding livestock. Unfortunately maize (corn) has two significant flaws; it lacks the full range of amino acids, namely lysine
Lysine
Lysine is an α-amino acid with the chemical formula HO2CCH4NH2. It is an essential amino acid, which means that the human body cannot synthesize it. Its codons are AAA and AAG....

 and tryptophan
Tryptophan
Tryptophan is one of the 20 standard amino acids, as well as an essential amino acid in the human diet. It is encoded in the standard genetic code as the codon UGG...

, needed to produce protein
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

s, and has its niacin (vitamin B3) bound in an indigestible complex. The Mayans and Aztecs used to boil maize in the alkaline limewater which broke down the complex so that the Niacin became available. However in the main this practice did not transfer to the Old World or settlers in the "New World" which resulted in epidemics of Pellagra from the 16th century onwards. In addition diets high in corn produce a condition known as wet-malnutrition - a person is receiving sufficient calories, but her or his body malfunctions due to a lack of protein. A chronic lack of protein in the diet leads to kwashiorkor
Kwashiorkor
Kwashiorkor is an acute form of childhood protein-energy malnutrition characterized by edema, irritability, anorexia, ulcerating dermatoses, and an enlarged liver with fatty infiltrates. The presence of edema caused by poor nutrition defines kwashiorkor...

.

Thus, conventional maize is a poor-quality food staple; unless consumed as part of a varied diet – which is beyond the means of most people in the developing world.

QPM produces 70-100% more of lysine and tryptophan than the most modern varieties of tropical maize. These two amino acids allow the body to manufacture complete proteins, thereby eliminating wet-malnutrition. In addition tryptophan can be converted in the body to Niacin, which theoretically reduces the incidence of Pellagra
Pellagra
Pellagra is a vitamin deficiency disease most commonly caused by a chronic lack of niacin in the diet. It can be caused by decreased intake of niacin or tryptophan, and possibly by excessive intake of leucine. It may also result from alterations in protein metabolism in disorders such as carcinoid...

.

Developing QPM

Modified maize with higher protein content dated back to the 1920s, and the “opaque-2” variety had been developed in 1963. While its lysine and tryptophan levels were better than those of conventional maize, opaque-2 had lower yields and a soft, chalky kernel, which made it more susceptible to ear rot and insect damage. Moreover, the taste and kernel appearance dissatisfied consumers, who ultimately rejected the enhanced-protein varieties in the market.

The Vasal-Villegas team

Surinder Vasal and Evangelina Villegas
Evangelina Villegas
Evangelina Villegas is a Mexican cereal biochemist whose work with maize led to the development of high-quality protein maize . She and her colleague, Dr. Surinder Vasal, shared the 2000 World Food Prize for this achievement....

 began their collaborative research in Mexico in the early 1970s while they were working at CIMMYT. Dr. Villegas was in charge of the lab investigating protein quality and Dr. Vasal was a plant breeder newly assigned to work on developing QPM varieties that would gain widespread acceptance.

Integrating cereal chemistry and plant breeding techniques, Drs. Vasal and Villegas collaborated to combine the existing opaque-2 maize with genetic modifiers. Through the 1970s, they produced and analyzed germplasms at an astonishing rate, sometimes processing up to 25,000 samples a year. By the mid-1980s, they had produced a QPM germplasm with hard kernel characteristics and good taste similar to the traditional grain and with much higher quality levels of lysine and tryptophan.

However, their discovery remained unexploited for years because many nutritionists felt that protein could be added to the diets of the most poor in other ways. In the early 1990s, CIMMYT gained the international support and funding to begin promoting QPM in Ghana
Ghana
Ghana , officially the Republic of Ghana, is a country located in West Africa. It is bordered by Côte d'Ivoire to the west, Burkina Faso to the north, Togo to the east, and the Gulf of Guinea to the south...

 and several other African countries. Since then, QPM has also yielded very positive results in China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

, Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

, and parts of Central America
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...

.

Impact of QPM

Babies and adults consuming QPM are healthier and at lower risk for malnutrition disorders such as marasmus
Marasmus
Marasmus is a form of severe protein-energy malnutrition characterized by energy deficiency.A child with marasmus looks emaciated. Body weight may be reduced to less than 80% of the average weight that corresponds to the height . Marasmus occurrence increases prior to age 1, whereas kwashiorkor...

 and kwashiorkor, and data from Latin America and Africa show the grain’s role in reversing the effects of malnutrition in those already affected. QPM offers 90% the nutritional value of skim milk, the standard for adequate nutrition value. At a time when UNICEF reports that 1,000,000 infants and small children are starving each month, the inclusion of QPM in daily rations improves health and saves lives. Additionally, pigs fed QPM experience rapid weight gain and are ready for market sooner or can provide an additional quality protein source for small farm families.

QPM hybrids have been developed and tested for varying climatic and growing conditions; QPM varieties are grown on roughly 9 million acres (36,000 km²) worldwide. Meanwhile, QPM research and development have spread from Mexico to throughout Latin America and to Africa, Europe, and Asia. In Guizhou, the poorest province in China, QPM hybrid yields are 10% higher than those of other hybrids, and the crop has enabled new pig production enterprises, bringing increased food security and disposable income. In total, the QPM germplasm has grown to contribute over $1 billion annually to the economies of developing countries.
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