Nutritional value of Amaranthus
Authors: Mahesh Kumar Samota

Amaranthus has been rediscovered as a promising food crop mainly due to its resistance to heat, drought, diseases and pests, and the high nutritional value of both seeds and leaves. Leaves are rich in proteins and micronutrients such as iron,calcium,zinc, vitamin C and vitamin A. Species of interest include: A. blitum, A. caudatus, A. cruentus, A. dubius, A. hypochondriacus, A. spinosus, A. thunbergii, A. tricolor, and A. viridis . Most of the amaranth species are harvested in the wild as food resource. Most countries in Africa are still struggling to address problems of under-nutrition and micronutrient deficiencies. Amaranths have excellent nutritional value because of their high content of essential micronutrients such asb-carotene, iron, calcium, vitamin C and folic acid. A. tricolor had higher magnesium levels than other vegetables. One cup of amaranth leaves, that are cooked, boiled, and drained contains 90 % vitamin C daily value requirement,73 % vitamin A, 28 % calcium and 17 % iron. The particularity of amino acid profile of A. cruentus leaves is its methionine and lysine levels, which are the limiting amino acids in most plant proteins. Wild species A. viridis, A. retroflexus, A. palmeri and A. blitoides had higher protein levels than the cultivated one A. hypochondriacus. Indeed, the highest amount of protein, vitamin A and iron were found in A. viridis whileA. dubius showed highest amount ofvitamin C, calcium and zinc. Amaranthus species,A. blitum, A. spinosus, A. tricolor, and A. viridis showed that the highest amount ofproteins, carbohydrates and calcium were found in A. spinosus while A. viridis contained the maximum amount of iron and sodium. Amaranth grain is also a good source of important minerals. It was reported that the amount of minerals such ascalcium, magnesium, iron and zinc in wheat grain are 5.2-, 2.9-, 2.8- and 1.3-fold lower than in amaranth seeds, respectively. Whole grains contain significant amounts of phytic acid, a well-known inhibitor of iron absorption and other minerals.

Nutraceutical properties of amaranths

Amaranth seed or oil may benefit those with hypertension and cardiovascular disease, regular consumption reduces blood pressure and cholesterol levels, while improving antioxidant status and some immune parameters. Vegetable amaranths are recommended as a good food with medicinal properties for young children, lactating mothers and for patients with constipation, fever, hemorrhage, anemia or kidney complaints. In Ghana the water of macerated plants is used as a wash to treat pains in the limbs. In Ethiopia, A. cruentus is used as a tapeworm expellant.The ash from the stems is used as a wound dressing In Sudan. In Gabon heated leaves were used on tumors. Amaranthus tricolor and A. caudatus are used externally to treat inflammations, and internally as a diuretic. the seed of A. spinosus is used as a poultice for broken bones. It is used internally in the treatment of internal bleeding, diarrhoea and excessive menstruation. A decoction of the root is used to treat gonorrhoea and is also applied as an emmenagogue and antipyretic in Southeast Asia. The leaves are also used for gastroenteritis, gall bladder inflammation, abscesses, arthritis and for the treatment of snakebites. The plant sap is used as an eye-wash to treat ophthalmia and convulsions in children. During the rainy season, A. spinosus bark decoction is taken to ward off malaria.

References:

Akubugwo I, Obasi N, Chinyere G, Ugbogu A (2007) Nutritional and chemical value of Amaranthus hybridus L. leaves from Afikpo, Nigeria. Afr J Biotechnol 6(24):2833-2839



About Author / Additional Info:
I am currently pursuing Ph.D. in Biochemistry from IARI new delhi