Nigella sativa (PROSEA)
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Introduction |
- Protologue: Sp. pl.: 534 (1753).
- Family: Ranunculaceae
- Chromosome number: 2n = 12
Synonyms
- Nigella cretica Miller (1768),
- N. indica Roxb. ex Fleming (1810)
Vernacular names
- Black cumin, small fennel, love-in-a-mist (En).
- Cumin noir, nigelle cultivée, toute-épice (Fr)
- Indonesia: jinten hitam
- Malaysia: jintan hitam.
Origin and geographic distribution
N. sativa is probably indigenous to the Mediterranean region and the Middle East up to India. Black cumin has long been cultivated and is mentioned in ancient Hebrew, Greek and Roman texts. It is cultivated in the subtropical belt extending from Morocco to northern India and Bangladesh, in East Africa and in the former Soviet Union. In Europe, North America and South-East Asia it is cultivated on a minor scale, mainly for medicinal purposes.
Uses
The seeds of N. sativa are used as a spice. Whole or crushed seeds are mixed through dough or sprinkled on bread in Sri Lanka, India, the Middle East, Turkey, the former Soviet Union, Egypt and Ethiopia. Crushed seeds impart a black colour to the bread. Black cumin is an essential ingredient of semi-sweet breakfast rolls and coffee cakes known as "choereg” in the Middle East. The seeds are used to flavour a variety of dishes ranging from sauces, curries, pickles and meat dishes to vegetables, fruit pies and other confections and in flavouring vinegar and alcoholic beverages. In Arab countries a few seeds mixed with honey are taken as a sweet.
In Islamic tradition N. sativa seeds are reputed to be a panacea. They also play an important role in Western herbal medicine, and consequently the seeds are traditionally used to treat numerous diseases, e.g. headache, rheumatic pains, asthma and coughs. Crushed seeds in vinegar are applied in skin disorders such as ringworm, eczema and baldness. N. sativa is also applied as a galactagogue, emmenagogue, vermifuge and diuretic and to aid discharge of pus. The pounded seeds are used against nausea and in parts of northern India to induce abortion. The seed is reported to have anthelmintic and carminative properties. A powdered mixture of seeds of N. sativa with Trigonella foenum-graecum L., Lepidium sativum L., Commiphora sp. and the dried leaves of Cleome droserifolia (Forssk.) Delile, Ambrosia maritima L. and Centaurium pulchellum (Sw.) Druce, administered as tea, is used in Egypt to treat diabetes.
In the United States the regulatory status "generally recognized as safe” has been accorded to black cumin (GRAS 2342) and black cumin oil (GRAS 2237).
The seeds are said to protect woollen goods and linen against insects. Although less popular than N. damascena L., N. sativa is also grown as an ornamental.
Production and international trade
Although N. sativa seed is traded internationally, no statistics on production and trade are available.
Properties
The odour of crushed black cumin seeds is reminiscent of lemon with a suggestion of carrot; the taste is strong, pungent and peppery, but also aromatic and nutty. To others it somewhat resembles oregano. The seed contains numerous esters of unsaturated fatty acids and terpene alcohols (7%) and about 0.5% essential oil. The essential oil is a yellow liquid with an unpleasant smell that tastes like juniper berries. The main components of the essential oil are thymoquinone (25-50%), p-cymene and α-pinene, further traces of carvacrol, anethole and α-terpineol.
Per 100 g edible portion, N. sativa seed contains approximately: water 4 g, protein 22 g, fat 41 g, carbohydrates 17 g, fibre 8 g, ash 4.5 g (Na 0.5 g, K 0.5 g, Ca 0.2 g, P 0.5 g, Fe 10 mg), thiamine 1.5 mg, pyridoxine 0.7 mg, tocopherol 34 mg and niacin 6 mg. The fatty oil is composed of eicosenoic acid (0.5%), linoleic acid (about 60%), linolenic acid (0.3%), myristic acid (0.3%), oleic acid (about 25%), palmitic acid (about 12%) and stearic acid (3%).
The seed also contains tannins, the alkaloids damascenine, nigellone, nigellimine, nigellimine-N-oxide and nigellicine, the sterols cholesterol, campestrol, stigmasterol, β-sitosterol and α-spinasterol. Further it contains about 1.5% of the glucoside melanthin, which on hydrolysis yields the toxic malanthogenin.
The effectiveness of N. sativa seeds in the treatment of several diseases has been confirmed experimentally. The lipid part of the ether-extracted seeds exhibits galactagogue action in buffaloes, goats and rats. Aqueous extracts have a broncho-dilatory effect explaining the effectiveness of N. sativa against cough. The effect is attributed to thymoquinone, but other compounds also play a role. Powdered seeds are as effective as commercial niclosamide against the tapeworms Taenia saginata and Hymenolepis nana in children. Powdered seeds have also been found to be effective against the tapeworm Moniezia expansa in sheep. Extracts of the seeds are currently being tested for their effect against rheumatism and related inflammatory diseases, in reducing the side-effects of chemotherapy in the treatment of cancer and in invigorating the immune function in humans.
Adulterations and substitutes
A high ratio of eicosadienoic acid to eicosamonoenoic acid combined with a high level of C20 fatty acids is highly characteristic of the seed oils of Nigella and could serve as a criterion for identifying genuine black cumin seed oil.
Composition
Black cumin oil (Source: Aboutabl et al., 1986.)
- 31.7% para-cymene
- 24.5% thymoquinone
- 9.4% ethyl linoleate
- 9.3% α-pinene
- 2.8% ethyl hexadecanoate
- 2.7% ethyl oleate
- 2.2% β-pinene
- 1.6% limonene
- 1.1% carvacrol
- 0.8% sabinene
- 0.6% thymohydroquinone
- 0.6% terpinen-4-ol
- 0.5% γ-terpinene
- 0.5% myrcene
- 0.4% bornyl acetate
- 0.4% longifolene
- 0.3% butyl propyl disulfide
- 0.2% ethyl tetradecanoate
- 0.2% ethyl octadecanoate
- 0.2% methyl linoleate
- 0.2% carvone
- 0.2% α-longipinene
- 0.1% artemisia ketone
- 0.1% p-cymen-8-ol
- 0.1% 2-heptenal
- 0.1% 1,8-cineole
- 0.1% trans-sabinene hydrate
- 0.1% ethyl octanoate
- 0.1% camphene
- 0.1% α-terpinene
- 0.1% terpinolene
- 0.1% linalool
- 0.1% camphor
- 0.1% (E)-anethole
- 0.1% 2-undecanone
- trace β-phellandrene
- trace borneol
- trace β-thujone
- trace cis-sabinene hydrate
- trace ethyl hexanoate
- trace ethyl heptanoate
- trace ethyl nonanoate
- trace dipropyl disulfide
- trace dibutyl disulfide
- 91.4% total
Description
- Erect annual herb, up to 70 cm tall, with a well-developed yellow-brown taproot and numerous feeder roots. Stem profusely branched, subterete, ribbed, sometimes hollow when old, puberulous, light to dark green.
- Leaves alternate; stipules absent; petiole strongly broadened at base, light green, only present in basal leaves, 1-6 cm long, ribbed, puberulous; blade up to 7 cm × 5 cm in outline, bi-, tri- or even multi-pinnately dissected into short, thin sublinear, divergent, slightly pilose lobes, which are normally green but sometimes turn reddish brown.
- Flowers terminal, solitary; pedicel (2-)4-8(-11) mm long, puberulous, ribbed; all flower parts inserted on a pale yellow, fleshy, depressed-conical receptacle, about 2 mm in diameter, visible as an orange-brown ring below the carpels in fruit; sepals 5, petaloid, ovate, 13-17 mm × 6-12 mm, apex obtuse, tapering basally into a 2-3 mm long claw, papillose to pilose, pale green when young, sometimes partly reddish, inside pale blue-white when older; petals (6-)8(-11), with short claw, blade 2-lobed, lobes enclosing nectar-pocket, dorsal lobe 3.5-5.5 mm × 2.5-4.5 mm, apex bifid, greenish-white with violet lines, ventral lobe oblong, 2.5-4 mm long, violet at base, white at apex; stamens in (6-)8(-10) groups of 3-7 stamens each, each group forming a spiraloid line on the receptacle, filaments linear, 3-9 mm long, violet-blue to pale blue, anthers yellow; pistil lobed, composed of 3-7 white-granular carpels, almost connate at base, forming a compound ovary 4-9 mm long with free stigmas.
- Fruit a ribbed, oblongoid, tuberculate capsule, 6-16 mm × 5-12 mm, greyish-green to brown at maturity, many-seeded, with persistent stigmas.
- Seed 3(-4)-sided, obpyramidal, 3 mm × 1.5-2 mm, rugose-tuberculate, dark black, with a carrot-like smell; embryo minute, embedded in copious, fatty endosperm.
Growth and development
Germination is epigeal. In temperate climates black cumin starts flowering about 100 days after sowing and seed reaches maturity 50 days later. In warmer climates, flowering may start 8-10 weeks after germination. Flowering is protandrous and pollination is believed to be mainly by insects. In older flowers the stigmas bend down and self-pollination may occur.
Other botanical information
N. sativa is a rather variable species but quite easily distinguishable from the other 13 species in the genus because of its blue, petaloid sepals, not involucrate flowers, three-sided seeds, tuberculate capsular fruits with carpels united to apex. Some subdivisions into forms or varieties have been made on the basis of seed colour, branching habit and hairiness, but these have no practical value. Sometimes a botanical division between wild and cultivated taxa is proposed, in which the wild plants are more hairy with smaller flowers and more tuberculate fruits. A cultivar classification would be appropriate for the cultivated plants, but as far as is known, no such system exists.
In the literature there is much confusion about the vernacular names that are used for N. sativa. "Black cumin” is also used for seeds of the cultivar "Black” of cumin (Cuminum cyminum L.) and for the seeds of Bunium persicum (Boiss.) B. Fedtsch. from the Middle East which are also used as a condiment. The appellations "small fennel” or "fennel flower” (alluding to the finely cut leaves) could lead to confusion with true fennel, Foeniculum vulgare Miller. "Love-in-a-mist” usually refers to the ornamental species such as Nigella damascena L., originating from southern Europe and cultivated worldwide for its attractive blue flowers which are surrounded by an involucre of green leaf lobes; the seeds (also black) are not usually used as a condiment.
Ecology
N. sativa is a hardy crop and can grow under a wide range of temperatures, from 5-25°C, the optimum being about 14°C. In Ethiopia, it is cultivated as a rainfed crop in the highlands at 1500-2500 m altitude. It is successfully grown in most kinds of soil with pH 5-8.
Propagation and planting
N. sativa can easily be propagated by seed. Germination is promoted by darkness and high temperatures. Seed is broadcast as seedlings are too fragile for transplanting, but seed may also be sown in peat blocks. A row spacing of (15-)25-40 cm is common. In Ethiopia, N. sativa is often intercropped with barley and wheat.
Husbandry
N. sativa responds favourably to fertilizers. Application of fertilizer at a per ha rate of 80 kg N, 17.5 kg P and 33 kg K has been reported to give seed yields of 1 t/ha.
Diseases and pests
There are no serious diseases in N. sativa. A minor leaf-spot is caused by Cercospora nigellae. Empty carpels may be caused by borer larvae. Larvae of Spodoptera litura may bring about 15-20% economic damage, but they can be controlled by applying 0.05% monocrotophos followed 10 days later by 0.2% carbaryl.
Harvesting
Since fruits of N. sativa dehisce easily, they should be harvested before they are completely dry.
Yield
Information on yields of N. sativa is scanty; yield levels have been reported of up to 1 t/ha in experiments.
Handling after harvest
The seeds of N. sativa can be removed by light threshing. They must be stored under dry conditions to maintain their characteristic spicy flavour. Under normal dry room conditions, seed remains viable for 2-3 years. Broken seeds deteriorate rapidly, due to the activity of lipases.
Genetic resources and breeding
Since N. sativa is cultivated in a very wide area, it is not at risk of genetic erosion. A small germplasm collection is maintained at the Western Regional Plant Introduction Station, United States. Studies have been initiated to compare the chemical and morphological characteristics of different provenances of N. sativa.
Prospects
The widespread use of N. sativa in oriental cooking and in traditional medicine ensures future interest in the crop. The current interest in herbal medicine, together with the interest being shown in the crop by the pharmaceutical industry may boost the importance of N. sativa. Crop production needs to be improved through agronomic and breeding research.
Literature
- Ahmed, N.U. & Haque, K.R., 1986. Effect of row spacing and time of sowing on the yield of black cumin (Nigella sativa). Bangladesh Journal of Agriculture 11(1): 21-24.
- Akhtar, A.H., Ahmad, K.D., Gilani, S.N. & Nazir, A., 1996. Anti-ulcer effects of aqueous extracts of Nigella sativa and Pongamia pinnata in rats. Fitoterapia 67(3): 195-199.
- Akhtar, M.S. & Riffat, S., 1991. Field trial of Saussurea lappa roots against nematodes and Nigella sativa seeds against cestodes in children. Journal of the Pakistan Medical Association 41(8): 185-187.
- Jansen, P.C.M., 1981. Spices, condiments and medicinal plants in Ethiopia, their taxonomy and agricultural significance. Centre for Agricultural Publishing and Documentation (Pudoc), Wageningen, the Netherlands. pp. 76-85.
- Khan, S.A. & Chatterjee, B.N., 1982. Fertilizer used by Nigella sativa in West Bengal, India. Indian Journal of Agricultural Science 52(6): 384-387.
- Nergiz, C. & Ötles, S., 1993. Chemical composition of Nigella sativa L. seeds. Food Chemistry 48: 259-261.
- Takruri, H.R.H. & Dameh, M.A.F., 1998. Study of the nutritional value of black cumin seeds (Nigella sativa L.). Journal of the Science of Food and Agriculture 76: 404-410.
Sources of illustrations
Jansen, P.C.M., 1981. Spices, condiments and medicinal plants in Ethiopia, their taxonomy and agricultural significance. Centre for Agricultural Publishing and Documentation (Pudoc), Wageningen, the Netherlands. Fig. 8, p. 79. Redrawn and adapted by P. Verheij-Hayes.
Authors
- I.B. Ipor & L.P.A. Oyen
