Carum ajowan
Carum ajowan
Ajowan (Carum ajowan Benth. & Hook.f.) is a herbaceous species belonging to the Apiaceae family.
Systematics –
From a systematic point of view it belongs to:
Eukaryota Domain,
Kingdom Plantae,
Magnoliophyta Division,
Magnoliopsida class,
Subclass Asteridae,
Order Apiales,
Apiaceae family,
Subfamily Apioideae,
Genus Carum,
C. ajowan species.
Basionimo is the term:
– Trachyspermum ammi (L.) Sprague ex Turrill.
The terms are synonymous:
– Ammi copticum L.;
– Ammi glaucifolium Blanco;
– Ammios muricata Moench;
– Apium ammi (L.) Urb.;
– Athamanta ajowan Wall.;
– Bunium copticum (L.) Spreng.;
– Carum ajowan Benth. & Hook.f.;
– Carum aromaticum Druce;
– Carum copticum (L.) Benth. & Hook.f. Ex C.B.Clarke;
– Cyclospermum ammi (L.) Lag.;
– Daucus anisodorus Blanco;
– Daucus copticus (L.) Lam.;
– Daucus copticus (L.) Pers.;
– Helosciadium ammi (L.) Britton;
– Helosciadium ammi (L.) Oken;
– Ligusticum ajawain Roxb. ex Fleming;
– Ligusticum ajawain Spreng.;
– Ptychotis ajowan DC.;
– Ptychotis coptica (L.) DC.;
– Selinum copticum E.H.L.Krause;
– Seseli foeniculifolium Poir.;
– Sison ammi L.;
– Trachyspermum copticum (L.) Link..
Etymology –
The term Carum is of controversial etymology: according to some authors, from κάρον cáron Greek name of Carum carvi in Dioscorides; for others from the Greek κάρυον cáryon every fruit with a hard, woody shell; according to Pliny it would derive from the country of origin, in Asia Minor, Κᾱρία Carίa in Greek and Caria in Latin.
The specific epithet ajowan is a term derived from the Hindi अजवाइन (ajvāin).
Geographic Distribution and Habitat –
Carum ajowan is an annual herbaceous plant native to the Middle East, in a territory between Persia and India and, probably, also Egypt, from which it spread to other regions and is currently cultivated and used in the Indian subcontinent and South Asia, but also in Iran, India, Pakistan, Egypt and Afghanistan and, in any case, present from Europe to East Asia and the Himalayas. Gujarat and Rajasthan are regions of India well known for growing this plant.
Its habitat is that of humid enough for its germination but in any case in arid and subarid and subtropical regions, at altitudes from sea level up to 2,200 meters.
Description –
Ajowan is an upright, aromatic, branching annual herb that grows between 60 and 160cm tall.
The stem is streaked and the white flowers are collected in inflorescences.
The flowers are small, pentamers, with radiated symmetry, and therefore consist of 5 petals and 5 reduced sepals, the androecium is formed by 5 stamens, the ovary is inferior formed by two carpels. The ovary bears two styles which widen at the base in a nectarous disk.
The dried fruits are diachenes which split in two when ripe, each part containing a seed; they are small and grayish-brown in color.
Cultivation –
Carum ajowan is a plant that naturally tends to grow in arid or sub arid regions.
The plant is often cultivated, especially in South Asia, for its seed which is used as a spice but also has a wide range of medicinal applications.
Ajowan can be grown in tropical and subtropical areas at altitudes from sea level up to 2,200 meters. It grows best in areas where annual daytime temperatures are between 16 and 24 ° C, but can tolerate between 10 and 30 ° C. in general it prefers an average annual rainfall in the range 800 – 1,000 mm, but tolerates 700 – 1,100 mm.
For the best yields it requires a moist soil in a sunny position and, from a pedological point of view, it prefers clay soils that are not too heavy, but it can be grown on all types of soil and prefers a pH between 6.5 and 7.5. tolerating 6 – 8.
Flowering begins 2 – 4 months after sowing and the seeds ripen 2 months later.
About 70 – 80% of the crop is cross pollinated and pollination is done mainly by bees.
Since the plants are widely branched, flowering occurs unevenly, so the seeds ripen unevenly, which makes them difficult to harvest.
The seeds are often harvested before they are fully ripe, to avoid losses due to crushing.
The quality of the essential oil of these fruits is considered equal to that of ripe fruits.
In India, traditionally grown Ajowan yields are higher in rain-only conditions than in irrigated crops and amount to about 225 kg / Ha of fruit. The selected cultivars can give yields of 1.2 – 2.2 tons / Ha and productions of over 8o kg / Ha of essential oil have been reached.
Propagation occurs by seed. Germination usually takes 10 – 15 days, although it can take up to 1 month.
Cool, cloudy weather and light rain after sowing are important for the establishment of the crop.
The seed is often spread at a rate of 2.3 – 3.5 kg per hectare, or even in intercropping with cereal crops or other Apiaceae.
The seed must be covered with a thin layer of soil for good germination and to prevent the sun and heat from compromising germination.
It is difficult to get a good seed, as many fruits for sale in the market are empty.
Customs and Traditions –
Carum ajowan, also known by the synonym of Trachyspermum ammi, takes various names including: ajwain, ajowan but also carom, Ethiopian cumin, wild parsley and bishop’s weed, in English and many other names in other languages, including: netch (white ) azmad (Amharic), kamun al-mulaki, taleb el koub (Arabic), joni-gutti (Assamese), jowan, yamani (Bengali), yan-jhon-wuihheung (Cantonese), nanava (Farsi), ajowan (German, French and Italian), ayamo, yavan (Gujarati), ajwain, carom omum (Hindi), ajamoda, oma (kannada), ayowan (Korean), ajowan (Japanese and Spanish), ayamodakam (Malay), yin-dou-zeng- hui-xiang (Mandarin), java (Nepalese), oregano-semente, ajowan (Portuguese), ajavain (Punjabi), assamodum (Sinhala), omam (Tamil), omu (Telegu), chilan (Thai) and misir anason (Turkish ).
Both the leaves and the seed-like fruit of the plant are consumed by humans. The “seed” (ie the fruit) is often confused with the “seed” of lovage.
The small fruits of Ajwain have a bitter and spicy flavor, with a flavor similar to anise and oregano. They smell almost exactly like thyme because they also contain thymol, but they taste more aromatic and less subtle, as well as being a little bitter and pungent. Even a small number of fruits tend to dominate the flavor of a dish.
This plant is used both in food and medicine.
The fruits are widely used, especially in India, the Mediterranean and Ethiopia, as a condiment in savory dishes, including curries, legumes, bread and pastry snacks.
The fruit is usually dried, then toasted and ground into a powder.
From the whole plant and from the seed, an essential oil can be extracted which is sweeter than thyme oil and used as a flavoring.
In medicinal use, both seeds and essential oil are used.
Ajowan seed, and the essential oil it contains, has a long history of medicinal use throughout its range and the plant is often grown in other areas.
In India the essential oil is known as ‘ajowan oil’, and is included in the Indian Pharmacopoeia.
Considerable research has been carried out on the medicinal properties of the plant, and in particular on the essential oil of thymol it contains.
Thymol, the main constituent of the essential oil, is strongly antiseptic, while the whole essential oil of the seed exhibits strong antibacterial activity against many gram-positive and gram-negative bacteria. It also showed long-term antifungal activity against a range of soil and storage fungi.
Thymol also showed significant molluscicidal, nematodicidal and larvicidal effects.
The essential oil has been shown to have vasodilating and hypotensive activity, producing a reduction in blood pressure and heart rate; moreover, it showed effective antioxidant activity.
In general, therefore, the seed, and especially the essential oil contained in the seed, are strongly antiseptic, antispasmodic, aromatic, bitter, carminative, diaphoretic, digestive, diuretic, expectorant and tonic.
It is used internally in the treatment of colds, coughs, flu, asthma, diarrhea, cholera, colic, indigestion, wind, edema, arthritis and rheumatism.
Essential oil is considered strongly antiseptic and is used to remove internal parasites.
The seed is harvested when fully ripe and distilled for essential oil or dried for later use.
The seed contains about 4 – 6% of essential oil, of which 45 – 55% is the highly antiseptic essential oil consisting of thymol.
Essential oil is also added to cough medicines.
The root is carminative and diuretic.
Among other uses, it should be remembered that the essential oil is added to epoxy derivatives.
It is used in medicine and in perfumes. Essential oil is a potent germination inhibitor of potatoes stored at room temperature.
A semi-drying oil is obtained from the seed which is used for technical purposes.
Among the side effects, it is emphasized that pregnant women should not use ajowan due to the potential negative effects on fetal development and its use is not recommended during breastfeeding. Also in high quantities taken orally, this plant is considered toxic and can cause fatal poisoning.
Hydrodistillation of Carum ajowan fruits produces an essential oil consisting mainly of thymol, gamma-terpinene, p-cymene and more than 20 trace compounds which are predominantly terpenoids.
Preparation Method –
Carum ajowan fruits are widely used, especially in India, the Mediterranean and Ethiopia, as a condiment in savory dishes, including curries, legumes, breads and pastry snacks.
The fruit is usually dried, then toasted and ground into a powder before being used as a spice.
From the whole plant and from the seed, as mentioned, it is possible to extract an essential oil used as an aroma.
The fruits are rarely eaten raw; they are commonly dry roasted or fried in clarified butter. This allows the spice to develop a more subtle and complex aroma. It is used extensively in Indian subcontinent cooking, often as part of a chaunk (also called tarka), a blend of spices – sometimes with a little minced garlic or onion – fried in oil or ghee, which serves to flavor a dish at the end of cooking. It is also an important ingredient in the herbal medicine that is practiced there. In Afghanistan, the fruit is sprinkled on bread and biscuits.
Other applications of ajwain include incorporating the seeds into specific types of bread, such as naan and parathas. The seeds can also be used as a mouth freshener when mixed with lemon juice and black pepper and then dried. Or, the seeds can simply be used as an ingredient in hot tea.
It is sometimes used as an ingredient in the spice blend called berberé. Cooked with beans, in addition to flavoring them, reduces the flatulent effects caused by them.
Among the spices obtained with this plant we remember the Radhuni, obtained from the fruits of Carum roxburghianum, equivalent in flavor to Ajowan, used exclusively in India, Indonesia and Southeast Asia.
For pharmacological use there is still little high-quality clinical evidence that ajwain has anti-disease properties in humans; however it is sold as a dietary supplement in capsules, liquids or powders.
An extract of the plant is made as a prescription drug called methoxsalen (Uvadex, 8-Mop, Oxsoralen) supplied as a skin cream or oral capsule for the treatment of psoriasis, vitiligo re-pigmentation, or skin disorders of cutaneous lymphoma. Since methoxsalen has numerous interactions with disease-specific medications, it should only be prescribed by experienced doctors.
It is traditionally known as a digestive and antiseptic.
Finally, it is highlighted how Ajwain is used in traditional medicine practices, such as Ayurveda, in herbal blends in the belief that it can treat various ailments. There is still no evidence that the oral use of ajwain in herbal blends is effective or safe.
Guido Bissanti
Sources
– Acta Plantarum – Flora of the Italian Regions.
– Wikipedia, the free encyclopedia.
– GBIF, the Global Biodiversity Information Facility.
– Useful Tropical Plants Database.
– Conti F., Abbate G., Alessandrini A., Blasi C. (ed.), 2005. An annotated checklist of the Italian vascular flora, Palombi Editore.
– Pignatti S., 1982. Flora of Italy, Edagricole, Bologna.
– Treben M., 2000. Health from the Lord’s Pharmacy, Advice and experiences with medicinal herbs, Ennsthaler Editore.
Warning: Pharmaceutical applications and alimurgical uses are indicated for informational purposes only, they do not represent in any way a medical prescription; therefore no responsibility is taken for their use for curative, aesthetic or food purposes.