Macrotyloma uniflorum

Macrotyloma uniflorum
Horse Gram Seeds
Scientific classification
Kingdom:	Plantae
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Fabales
Family:	Fabaceae
Genus:	Macrotyloma
Species:	M. uniflorum
Binomial name
Macrotyloma uniflorum (Lam.) Verdc.
Varieties
M. uniflorum var. stenocarpum (Brenan) Verdc. etc.

Macrotyloma uniflorum (horse gram, kulthi bean, hurali, Madras gram) is one of the lesser known beans. The horse gram is normally used to feed horses, though it is also commonly used in cooking. In traditional Ayurvedic cuisine, horse gram is considered a food with medicinal qualities. It is prescribed for persons suffering from jaundice or water retention and as part of a weight loss diet.^[1] Although rich in proteins (20%), due to less acceptable taste and flavor of cooked products, it is consumed only by the farming community and low-income groups. Thus, it has remained an underutilized food legume. Horse Gram is mainly cultivated in India. It is also cultivated in Sri Lanka, Malaysia, West Indies etc. In India, this is grown in the states of Karnataka, Andhra Pradesh, Orissa, Tamil Nadu, Madhya Pradesh, Chhattisgarh, Bihar, West Bengal, Jharkhand and in the foot hills of Uttaranchal and Himachal Pradesh.^[2] It is consumed as a whole seed, as sprouts, or as whole meal in India, popular in many parts of India. Medical uses of these legumes have been discussed.

Horse gram and moth bean are legumes of the tropics and subtropics, grown mostly under dry-land agriculture. The chemical composition is comparable with more commonly cultivated legumes. Like other legumes, these are deficient in methionine and tryptophan, though horse gram is an excellent source of iron and molybdenum. Comparatively, horse gram seeds have higher trypsin inhibitor and hemagglutinin activities and natural phenols than most bean seeds. Natural phenols are mostly phenolic acids, namely, 3,4-dihydroxybenzoic, 4-hydroxybenzoic, vanillic, caffeic, p-coumaric, ferulic, syringic and sinapic acids.^[3] Dehusking, germination, cooking, and roasting have been shown to produce beneficial effects on nutritional quality of both the legumes. Though both require prolonged cooking, a soak solution (1.5% NaHCO₃ + 0.5% Na
₂CO
₃ + 0.75% citric acid) has been shown to reduce cooking time and improve protein quality. Moth bean is mostly consumed as dhal or sprouts.

Climate Requirements

Horse gram is an extremely drought-resistant crop. Moderately warm, dry climatic conditions are suitable for its optimum growth. It does not grow well on higher altitudes because of cool and wet climate. Horse gram can be cultivated up to an altitude of 1000 m above the sea level. The temperature range of 25 °C-30 °C and relative humidity between 50% and 80% is optimum for its growth. Heavy rains during the initial stages of crop growth affect nodule formation owing to poor aeration in the soil. A well-distributed rainfall of about 800 mm is sufficient for its successful cultivation, but it performs well even under low rainfall areas.^[2]

Characteristics

Horse gram is a short day, twining, succulent, annual climbing herb which has trifoliate leaves, white coloured flowers, long linear pubescent pods with curved beak, flattened small seeds with light red, brown, grey, black or mottled testa with photo and thermo-sensitive nature. It matures in 4 to 6 months. Horse gram germinates reasonably well in drought-prone areas with very poor soils (where other crops invariably fail to grow) due to Dehydrins (MuDHN1, MuDHN2 and MuDHN3) which appeared to be the principle stress responsive genes in various abiotic stresses besides, it is relatively tolerant to low to moderate salinity levels with pH up to 8 and heavy metal stresses compared to other pulse crops grown in semi-arid regions. However, it is sensitive to becoming waterlogged, and is completely intolerant of frost (Jones, 1969). Drought tolerance capacity of horse gram is attributed in parts to various pathways like antioxidant and osmolyte biosynthesis, making it sturdy enough to withstand long periods of drought with minimum management. It also exhibits amazing defense against attack by pests/pathogens and the possible source of the indomitable pest resistance may be due to a dual function protein that exhibits both lectin and lipoxygenase like functions. The crude extracts of horse gram plant possess compounds with antimicrobial properties with a broad spectrum of activity against both gram-positive and gram-negative bacteria and fungi.^[4]

Origins and climatic requirements

It is native to the old world tropics and indigenous to India. Archaeological investigations have revealed the use of horse gram as food especially in India as origin around 2000 BC. Horse gram belongs to the genus Macrotyloma and contains 25 species indigenous to Africa and Asia. Presence of wild or naturalized horse gram is recorded in Africa (Central, East and Southern Africa) and India. The primary center of origin and use of horse gram as a cultivated plant is in the plains and hills of low altitude extending southwards in the Western Ghats in South West India. During the Neolithic period, through counter-migration of human beings, its cultivation was diffused to the northern and western parts of the Indian subcontinent. It is generally grown in sub-humid to semi-arid climates with annual rainfall 300–600 mm, and also with less than 30 cm rainfall as a dry-land crop up to an elevation of 1800 m from mean sea level. The optimum temperature range for its growth is 25 °C to 32 °C; it can tolerate temperatures up to 40 °C, but the growth rate declines markedly below 20 °C.^[4]

Indian regional specifics

In India, it is also known as gahat, muthira, kulath, or kulthi, ಹುರಳಿ (hurali). It is used to make popular dishes like Chana,Chholey,kulitan saaru, kulitan upkari, kulitan ghassi (coconut curry preparation), and idli-like preparation (but not fermented) called kulitan sannan.

• In Punjab horse gram is called Chana and/or Chholey. It is a very popular dish all over world.

• In Telangana and Andhra Pradesh, horse gram (ulava (singular) ulavalu (plural), ఉలవలు) is prescribed for persons suffering from jaundice or water retention, and as part of a weight-loss diet. It is considered helpful for iron deficiencies, and is considered helpful for maintaining body temperature in the winter season. Ulavacharu (horse gram soup) is popular dish in Telangana and Andhra Pradesh, it is served with boiled rice in most of the Telugu-speaking people's weddings and ceremonies.
• In Darjeeling and Sikkim, horse gram (called (gahat in Nepali) is considered a medicinal food. It is given to children suffering from mumps. Water in which gahat is soaked is taken by people suffering from kidney stones in the belief that this dissolves the crystals. Gahat's use is specially reserved for the cold winters, when its heat-producing properties are most useful.
• In Kerala, horse gram, (called മുതിര (muthira) in Malayalam which almost sounds like കുതിര (kuthira), Malayalam word for horse), is used in special kinds of dishes.
• In Tamil Nadu, horse gram (called கொள்ளு (kollu, in the southern districts it is called kaanam) is commonly used in Tamil dishes, including kollu chutney, kollu porial, kollu avial, kollu sambar, and kollu rasam. In traditional siddha cuisine, horse gram is considered a food with medicinal qualities.
• In Maharashtra, and specifically the coastal Konkan region and Goa, horse gram (kulith) is often used to make kulith usal, pithla, and laddu.
• In Karnataka cuisine, ಹುರಳಿಸಾರು (hurali saaru), ಹುರಳಿ (hurali) is a main ingredient. Hurali is also used in preparations such as usali, chutney, basaaru, and upsaaru or upnesaru (particularly in the Old Mysore Regions Mandya and Chamrajnagara Districts).
• In South Canara region of Karnataka, in Tulu, it is also called kudu (ಕುಡು).
• In Odisha it is known by the name କୋଳଥ (Kolatha).
• Gahat or kulath is a major ingredient in the food of Pahari region of northern India.
• In Himachal Pradesh, kulath is used to make khichdi. In Uttarakhand, it is cooked in a round iron saute pan (kadhai) to prepare ras, a favorite of most Kumaonis. In Garhwal region, another more elaborate dish is phanu which is made in a kadhai with roughly ground gahat (previously soaked overnight) boiled over several hours. Towards the end, some finely chopped greens (palak or spinach, rai, tender radish leaves, or dhania(coriander leaves) if nothing else is available) are added to complete the dish. Served with boiled rice, jhangora (a millet-like grain, used as a staple by poorer Garhwalis only a decade ago and now a prized health-food)

In Myanmar (Burma), horse gram is known as pe bazat (ပဲပိစပ်). It is commonly used in making pon ye gyi, a fermented bean paste used in traditional Burmese cuisine.

Nutrition

Horse gram has been recognized as potential source of protein and other nutrients. It has high nutritional value equivalent to other commonly grown pulse crops in all aspects and also an excellent source of iron, molybdenum and calcium. Horse gram seed contains carbohydrate (57.2% w/w), protein (22% w/w), dietary fiber (5.3% w/w), fat (0.50% w/w), calcium (287 mg), phosphorus (311 mg), iron (6.77 mg) and calories (321 kcal) as well as vitamins like thiamine (0.4 mg), riboflavin (0.2 mg) and niacin (1.5 mg) per 100 grams of dry matter. However, several factors like the genotype, soil, fertilizer application, cultural practices, weather and climatic factors, post-harvest handling and storage can directly or indirectly affect the nutritional quality. Horse gram seed is low in fat and is excellent sources of protein, dietary fiber, a variety of micro-nutrients and phytochemicals still it has remained an underutilized food legume, consumed only by the farming communities of inaccessible areas and low-income groups.^[4]

Medicinal uses

Scientists from the Indian Institute of Chemical Technology have found that unprocessed raw horse gram seeds not only possess antihyperglycemic properties, but also have qualities which reduce insulin resistance. The scientists made a comparative analysis between horse gram seeds and their sprouts and found that the seeds have greater beneficial effects on the health of hyperglycemic individuals. The majority of antioxidant properties are confined to the seed coat and its removal would not do any good. Raw horse gram seed is rich in polyphenols, flavonoids, and proteins, major antioxidants present in fruits and other food materials. The seed has the ability to reduce postprandial hyperglycemia by slowing down carbohydrate digestion and reducing insulin resistance by inhibiting protein-tyrosine phosphatase 1 beta enzyme.^[5]

References

External links

• Kadam SS, Salunkhe DK (1985). "Nutritional composition, processing, and utilization of horse gram and moth bean". Crit Rev Food Sci Nutr. 22 (1): 1–26. doi:10.1080/10408398509527416. PMID 3899515.

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