Here is a list of eighteen medicinal plants that are mostly found in India.
1. Aconite:
The genus Aconitum belongs to the family Ranunculaceae. It comprises more than 100 species of herbs distributed over the northern temperate regions of the world. About 24 of them are found in India in the alpine and sub-alpine regions of the Himalayas, from Kashmir to the hills of Assam. The tuberous roots of quite a few species are regarded valuable for medicinal purposes.
A. napellus Linn. is a very important species. It does not occur in India, but is widely cultivated in some temperate regions of Europe and Asia. Formerly, the leaves and flowering shoots of the plant were utilized, but at present, only the roots are used. The plant is a perennial herb with a tuberous root, which is replaced annually by one or more daughter roots.
The daughter root commences to grow in the late winter or early spring and the parent root gradually perishes. The aerial stem attains a height of 45 to 60 cm in wild plants and 1 to 1.5 metres in cultivated plants. Leaves are palmatisect, the lower ones are being petiolate and the upper ones are nearly-sessile.
Inflorescence is a raceme and the flowers are zygomorphic and dark violet-blue in colour. Sepals 5 are petaloid. Petals 5-7, two modified into nectaries, and the remaining 3 to 5 inconspicuous. Stamens are numerous, surrounding 3, occasionally 5 carpels. Fruit is an etaerio of 3 to 5 follicles.
A.ferox (A. balfourii and A. deinorhizum) has been used in India for similar medicinal purposes under the name bish or vatsnabha. Another species, A chasmanthum, is found in India. It has a high percentage of alkaloids.
Aconite grows well in peaty soil containing a little lime. Propagation should always be done by means of tubers, because the seeds are often sterile and, besides, they may be produced as a result of hybridization with other species. In England, roots are collected in the autumn. Collection from plants, which are in flower, is generally recommended in Europe. This enables plants to be distinguished from other wild species. After collection, the tubers are dried.
Aconite contains, on an average, 0.3 to 1.2 percent of total alkaloids. These include the crystalline, ether-soluble alkaloid, aconitine and the amorphous products of its hydrolysis, benzoylaconine and aconine. Of these, aconitine is the most important.
Aconite is used internally in fevers and externally in cases of neuralgia and rheumatism. It is also used in diarrhoea, dyspepsia and cough.
2. Senna:
Senna is indigenous to Somaliland and Arabia. It is now cultivated in southern India in Tinnevelly, Madura and Tiruchirapally districts. It has been introduced in Karnataka and has been found to do well there. The leaves and pod-shells contain the active principle Sennocide. India is the chief producer of the crop and this country exports large quantities of leaves and pods every year, valued at about Rs. 60 lakhs.
Senna (Cassia angustifolia Vahl.) belongs to the family Caesalpineae. The plant, which is a perennial branched undershrub, attains a height of about 1 metre. Leaves are compound, paripinnate; lamina with entire margin, acute apex and more or less asymmetric base; both the surfaces pubescent.
The crop is usually cultivated on dry land, immediately after harvest of rice. The plant requires bright sunshine and occasional drizzles. It may be raised as a semi-irrigated crop and given a light irrigation. The crop is usually grown on marginal, red laterite soils, either as a pure crop or as a mixed crop with gram, sesame, chillies and cotton.
Sowing is done in February-March under irrigated conditions and in November under rain-fed conditions. About 15 kg seed per hectare is required in the former case and 27 kg in the latter. Seeds are sown either by broadcasting or by drilling in rows, 30 cm apart. One or two hoeing is necessary after the seedlings emerge. The crop is rarely fertilized.
However, application of 20 kg N and 40 kg P per hectare at planting, followed by that of 40 to 60 kg N per hectare in 3 split doses, has been recommended. After the plants have grown for 3-5 months, the first flush of flower stalks is cut off and this induces lateral branching. The leaves are stripped off when they are fully grown and are thick and bluish coloured.
After about a month, another stripping is done and the plants are allowed to produce seed. The third picking is done when the pods are plucked. The pods are collected a little before their maturity. The second crop of pods is obtained when the plants are uprooted during August or April-May.
The leaves and the pods are carefully dried in shade for 4 to 7 days; otherwise, the colour is spoiled and the content of the-active principle is lowered. The produce is graded, pressed and packed for despatch. The yield of leaves is 1 to 1.4 tonnes per hectare and that of pods about 1.5 quintals and 1 quintal per hectare under irrigated and rain-fed conditions, respectively.
Senna is a useful laxative and can be recommended for habitual constipation. It can be used occasionally. Owing to somewhat gripping effect, it is often used with carminatives. The laxative principle present in the leaves and the pod-shells is known as sennocide.
Senna is commonly attacked by damping off disease in the seedling stage and it can be controlled by treating the seeds with Captan. During storage of pods, considerable damage is done to them by the attack of borers.
3. Yams:
Yams belong to the genus Dioscorea of the family, Dioscoreaceae. They are climbing or twining herbs, usually cultivated throughout India. They thrive best in deep sandy loams and are resistant to drought. Propagation is done by pieces of tuberous roots weighing 50-70 g.
Species of Dioscorea have been cultivated since long chiefly for their starch-containing tubers. About 50 species are found in India. Certain non-edible species provide diosgenin, the raw material for industrial production of cortico-steroid drugs, including cortisone, which is regarded very valuable for treating a number of diseases and also for use in oral contraceptives.
Among these species, D. composita Hemsl. and D. floribunda Mart. & Gal. from Central America, D. deltoidea Wall, ex Kunth. and D. prazeri Prain & Burk. from the Himalayas are very important on account of the higher diosgenin content of their tubers. Certain other species of Dioscorea also possess medicinal properties.
They include D. oppositifolia Linn., D. pentaphylla Linn., D. esculenta Burkill. and D. bulbifera Linn., which are all found in India. The tubers of the first three are externally applied to reduce swellings and those of the last one are used as an application for ulcers and also used in piles, dysentery and syphilis.
Besides these, D. alata Linn., which is cultivated practically in all states of India for edible purposes and for extraction of starch from the tubers on a commercial scale, is considered anthelmintic and useful for leprosy, piles and gonorrhoea.
4. Nux-Vomica (Kuchila, Bailewa):
A valuable drug is obtained from the seeds of Strychnos nux-vomica L. of the family, Loganiaceae. The plant is an ever-green or deciduous tree native to Sri Lanka, India and Australia. In India, the plant grows in UP, Bihar, Orissa, AP, Karnataka and Tamil Nadu. Leaves are 8-15 cm long, broadly elliptic. Flowers are greenish white and are in terminal compound cymes.
Fruit is a globose berry, 2.5-5.0 cm in diameter. When ripe, it has a hard, orange-yellow epicarp and a white pulpy interior. Seeds are 1 to 5 in number and are grayish, hard and bitter. They are embedded in the pulp. Ripe seeds usually contain 2 to 3.5% of the important alkaloids, strychnine and brucine, about 1.23% of the former and 1.55% of the latter.
The action of the whole drug closely resembles that of strychnine. The alkaloid was formerly used as a circulatory stimulant in such cases as surgical shock. However, its use is now more limited to that of respiratory stimulant in certain cases of poisoning. Strychnine improves the appetite and digestion.
Powdered seed is used in chronic rheumatism, dyspepsia, intermittent fever, diarrhoea, hysteria and many other ailments. Leaves of nux-vomica are applied as a poultice on maggot-infested ulcers. Roots and bark are used in fevers. An infusion of bark is prescribed for epilepsy. Nux-vomica is an animal poison and is sometimes used as an insecticide.
5. Vasak (Basak, Arusi):
The drug is obtained from fresh leaves of the plant Adhatoda vasica Nees., which belongs to the family, Acanthaceae. The plant is found throughout the plains of India in wild condition and is cultivated on a small scale. Outside India, it is found in Bangladesh, Myanmar (Burma), Malaysia and Sri Lanka.
The plant is a gregarious, evergreen shrub, attaining a height of about 2.5 metres. The leaves are opposite, elliptic or elliptic-lanceolate, acuminate and up to 18 cm in length. Inflorescence is a dense terminal spike. Flowers are bisexual, zygomorphic and hypogynous.
Calyx is shordy campanulate with 5 lanceolate acute lobes. Corolla is bilabiate, white with pinkish-violet tinge at the throat, up to 3 cm long. Stamens 2, inserted at the throat of the corolla. Ovary is bicarpellary, syncarpous, 2-celled and superior; ovules 2 in each cell. Style is filiform and stigma entire. Fruit is a clavate capsule with 1 or 2 seeds.
A. vasica is a well-known drug in Ayurvedic and Unani systems of medicine and is prescribed for a variety of ailments, such as, bronchitis, asthma, fever, jaundice, consumption, etc. Leaves and roots are antispasmodic and very good for treatment of coughs.
Leaves contain a very small amount of an essential oil, an acid and a white crystalline alkaloid, vasicine. The medicinal properties of the plant are attributed to the alkaloid and the essential oil. Vasicine is further responsible for the insecticidal and antiseptic properties of the plant.
6. Chiretta (Chirata, Charayatha):
The drug, Chiretta, obtained from the dried plant of Swertia chirayita is regarded in India to be extremely valuable. The plant is found growing wild in the temperate Himalayas at elevations of 1,200-1,300 metres, from Kashmir to Bhutan and in the Khasi hills.
Chiretta or Swertia chirayita (Roxb. ex Flem.) Karst. belongs to the family, Gentianaceae. The plant is an erect annual herb, attaining a height of about 1.5 m. Stem robust and branching. Leaves are alternate, broadly lanceolate, and sub-sessile. Inflorescence is a raceme.
Flowers are small and bisexual. Sepals 4 are lanceolate, Petals 4, lanceolate, greenish yellow with a purple tinge. Stamens 4 are filaments free. Ovary superior and 1-celled with many ovules. Style is cylindrical and stigma bilobed. Fruit is a many-seeded capsule. Seeds are smooth and many angled.
The plant is propagated by seed, which is shed during October-November. Seeds are sown in a nursery and the seedlings are transplanted in the field later. Harvesting is done by uprooting and gathering the plants when capsules are fully formed. They are then dried carefully and made into bundles.
Chiretta contains two bitter principles, ophelic acid and chiratin, and is valued very much in India as a tonic and febrifuge. It is stomachic, anthelmintic, laxative, antiperiodic and antidiarrhoeic. In western India, it is regarded as a good remedy for bronchitis, asthma and liver ailments. It can be used for skin diseases with good results. Chiretta is given as an infusion or tincture.
7. Ephedrine (Khanda):
The alkaloid ephedrine is obtained from different species of the genus, Ephedra belonging to the family, Ephedraceae. The plants are much branched shrubs. Among these species are the Chinese ones, E. sinica and E. equisetina.
Four species occur in India, namely:
(i) E. gerardiana Wall – It is found in dry regions of temperate and alpine Himalayas at elevations of 2,100-4,800 m. Plants found in Dattamula in Kashmir are rich in alkaloids
(ii) E. intermedia Schrenk & Mey- It is a densely branched, erect or prostrate shrub, found in Pangi, Kanawar, Kashmir and Kulu.
(iii) E. major Host- It is an upright, rarely ascending, densely branched shrub, attaining a height of about 1.8 m.
(iv) E. foliate Boiss & Kotschy- It is a tall scandent shrub found in the plains of southern Punjab and Rajasthan.
Medicinal species of Ephedra can be grown in northern India at elevations of 2,400 m or more, in regions where the rainfall is 50 cm or less. Kulu is suitable for cultivation of E. gerardiana and E. major. Propagation of plants is done by seeds, layers or division of root- stock.
Seeds are sown by drills in early spring, the spacing within and between rows being 5 cm and 70 cm, respectively. Watering and weeding are done for a year or so. The best time for collection of green twigs, which constitute the Ephedra of commerce, is when the age of plants is 4 years.
Twigs should be collected much after the rainfall and before the start of winter frost. Green twigs have been found to be richer in alkaloids than the woody stems. After collection, the twigs are dried in the sun. Among the Indian species, E. major is the richest source of ephedrine.
The drug obtained from the plant is valuable on account of the presence in it of the alkaloids, ephedrine and pseudo-ephedrine. Ephedrine is used for the relief of asthma and hay fever and also for other medicinal purposes. Its action is similar to adrenaline, but is more prolonged.
Another advantage is that it may be administered by mouth and need not be injected. The tincture of the plant is a stimulant, both cardiac and respiratory. Ephedrine reinforces heart action and dilates the bronchi and hence it is very commonly used in bronchial asthma.
8. Kurchi:
Kurchi has long been valued for the anti-dysenteric properties of its stem-bark. The plant of Kurchi, Holarrhena antidysenterica L. (Apocynaceae) is a deciduous shrub or a small tree, found almost throughout India, up to an altitude of 1,200 metres. Leaves are opposite, sub-sessile, elliptic or ovate-oblong and membranous. Flowers are white, in corymbose cymes. Follicles cylindrical, 15-45 cm long, usually white spotted. Seeds are 25-30 in a follicle. Kurchi has several alkaloids, the principal being conessine (0.4%).
The bark is astringent, antidysenteric, anthelmintic and stomachic. It has febrifugal and tonic properties as well. It is used for curing amoebic dysentery and diarrhoea. As compared to emetine, it has a slow action, but it is less toxic and can be administered orally. The bark is also used in piles, colic, chest affection and diuresis.
Besides, it is considered useful for diseases of spleen and skin. Sometimes, a hot decoction is used as gargle in toothache. Seeds and leaves are also quite useful; the former have similar properties as bark and the latter are good for bronchitis, boils and ulcers.
9. Indian Aloe (Ghrita Kumari, Ghee Kunvar):
Indian Aloe (Aloe barbadensis Mill.), which belongs to the family Liliaceae, is an important medicinal plant found all over India. It is a native of North Africa, Canary Islands and Spain. It has now spread to West Indies, Indonesia, India, China and certain other countries. Quite a few forms of the species are naturalized in India and are found growing in a semi-wild state in different parts of the country.
The plant is coarse-looking, with a short stem, 30-60 cm in height. Leaves are fleshy, about 38 cm long, 10 cm broad and 1.9 cm thick and are densely crowded.
The leaves are used as remedy for various diseases. After removal of the skin, they are given to persons suffering from fevers, enlargement of the liver and the spleen, constipation, jaundice, rheumatism, certain skin diseases, etc. It is regarded valuable for piles. The mucilage has a cooling effect and is used as poultice in inflammations. The leaf-juice is used for removal of intestinal worms in children.
10. Stramonium:
Stramonium consists of dried leaves and flowering tops of Datura stramonium Linn., belonging to the family, Solanaceae. The plant occurs as a common weed all over India, up to an altitude, of 2,440 metres. It is a glabrous annual, about 1 metre in height; under favourable conditions, the plant may attain a height of about 1.8 metres. The stem is erect with spreading branches. Leaves are pale-green, ovate or triangular ovate, 12.70-15.25 cm long, irregularly toothed. Flowers are large, 7.65-20-.30 cm long, white or violet coloured. Capsule erect, ovoid, thickly covered with sharp spines. Seeds are many, reniform.
Plants are harvested when fruits are mature but green, and they are partially dried. Leaves are separately dried after stripping them and seeds are shaken off from capsules when they start bursting.
Stramonium, which is obtained from leaves, contains 0.3-0.5% alkaloids, chiefly hyoscyamine and small quantities of atropine and scopolamine. Stramonium has narcotic and antispasmodic properties and is used to relieve spasm in asthma. Cigarettes made of the leaves are sometimes smoked for the purpose. Leaves are also used in Parkinsonism and boils, sores, etc. Whereas the juice of flowers is good for ear-ache, the juice of fruits is beneficial for curing dandruff and loss of hair.
An alkaloid, daturin, is obtained from the roots, which is poisonous and can be used for the treatment of asthma. The seeds too have narcotic properties and are sometimes used for poisoning.
11. Santonin:
The drug, santonin, is obtained from the species of the genus, Artemisia, belonging to the family Compositae. Plants are hardy and they can withstand extremes of temperature. A. maritima L. is found in western Himalayas, from Kashmir to Kumaun, at elevations of 2,100-2,700 m. It is a shrubby aromatic species, about a metre in height. Stems are erect or ascending much branched from the base.
The entire plant is used medicinally, but the leaves are preferred. Fresh plants are more efficacious than dry ones. In Artesmesia of Kurram Valley in Pakistan, santonin has been found concentrated only in the leaves up to about the second week of June. The maximum content of the drug is reached between the end of May and the end of June, when flower-buds begin to appear.
After this, santonin passes into the buds, where the maximum, is reached when they are fully developed. There is a rapid fall in the santonin-content when the buds open. For profitable use, the plant should contain at least 1.2% santonin. The Russian Artemesia (A. cina) is generally richer in santonin-content than the Indian species.
Santonin is used as vermifuge and also as stimulant and tonic. It is very efficient in its action on round worms and is less effective on thread worms.
12. Arjun:
The plant is found in most parts of India and is regarded valuable for different properties. It commonly grows in MP, Bihar and in the western parts of the Indian Peninsula.
Arjun or Terminalia Arjuna (Roxb. ex DC.) Wight and Arn. belongs to the family Combretaceae. It is a large evergreen tree with spreading crown and drooping branches. Leaves are oblong or elliptic, coriaceous. Fruits are ovoid or ovoid-oblong and nearly glabrous.
The bark of the tree, which is acrid, has valuable medicinal properties. It is a febrifuge and has a cooling effect. It further acts as a cardiac stimulant. It is commonly prescribed in heart diseases, for which it is an excellent remedy. The decoction is taken with milk every morning. The powdered bark seems to give relief from complaints of hypertension. In cases of cirrhosis of the liver, it has a diuretic effect. Besides, it also produces a general tonic effect.
13. Kalmegha (Kalomegh):
Kalmegha (Andrographis paniculata Nees.) belongs to the family Acanthaceae. It is a very useful plant and is found in the plains almost throughout India. The plant is an erect herb, attaining a height of about 92 cm. It produces small, pink flowers in lax racemes or panicles, 7-9.5 cm long. Seeds are many, rugose and glabrous.
The plant is used in cases of bronchitis, dyspepsia, dysentery, influenza, etc. The decoction made of the plant and the powders of the seeds are also considered to be good for fevers. The plant is regarded very valuable as a febrifuge, alterative and bitter tonic and is sometimes used as a substitute for chiretta.
14. Liquorice (Jastimadhu, Mulhatti):
The plant is indigenous to the Mediterranean region and is distributed in sub-tropical and warm temperate regions. It is grown in Iraq Iran and Central Asian countries. In India, it is grown on a small scale in Jammu and Kashmir, Punjab and in Dehradun.
Liquorice (Glycyrrhiza glabra L.) belongs to the family, Papilionaceae. The plant is a hardy, perennial herb or undershrub, attaining a height of about 1.8 m. The underground parts in some varieties consist of a root stock with a number of long branched stems; in others, they consist of the stout root stock, which throws off a large number of perennial roots. The dried underground stems and roots constitute the drug known as Liquorice.
Harvesting is done in 3-4 years, when the roots get ready. After harvest, which is done by digging up the plants in autumn, after the rains, the roots and underground stems are cut into pieces and dried slowly under cover. A portion of the harvested material is decorticated before drying and the peeled liquorice of commerce is thus obtained.
The underground parts contain glycyrrhizin (2-14%) and are sweet, demulcent, mildly laxative and expectorant. Liquorice is prescribed as a remedy for coughs, bronchitis, asthma and certain urinary troubles. The extract is supposed to produce a healing effect in gastric ulcers.
15. Croton (Jamalgota):
A fatty oil is obtained from dried ripe seeds of croton plant (Croton tiglium Linn.), which belongs to the family Euphorbiaceae. The plant is a shrub or small tree, indigenous to South-east Asia. It is now distributed in West Bengal, Assam, south India, Myanmar (Burma) and Sri Lanka. Fruits are 3-lobed, 17-25 mm long, almost glabrous and 3-seeded. Seeds are albuminous, oblong and rounded at the extremities.
Endosperm reddish brown and rich in oil. The oil amounts to 30-45% of the whole seed and 43-63% of the kernel and is obtained either by expression or extraction with solvents. The oil is yellowish-brown in colour and is viscid. It has a bad odour and the taste is mild at first, but becomes sharp and acrid afterwards. The seed and the oil have dangerous toxic and purgative properties.
Croton oil is the most powerful purgative known. It causes vomiting also. It is used to a limited extent, usually in admixture with certain diluents. It is more frequently used as a liniment and a stimulant in cases of pneumonia, gout, chronic rheumatism, sciatica, neuralgia, paralysis, etc.
16. Eucalyptus:
The essential oil obtained by distillation of dried scimitar-shaped leaves of the plant, Eucalyptus globulus Labill., belonging to the family Myrtaceae, is widely used as a medicine. The tree is a native of Australia and it reaches a height of 60 to 90 metres. It is cultivated in India in the Nilgiris, the Palni Hills, Shimla Hills and Meghalaya.
Eucalyptus oil is pale yellow or colourless and it has a pungent odour. It is used chiefly in the treatment of nose and throat disorders, malaria and other fevers and also in perfumery. It is also used as mosquito and vermin repellent
17. Chaulmoogra:
Chaulmoogra (Teraktogenos kurzii King.) belongs to the family, Flacourtiaceaes. The plant is a native of Burma and other parts of South-eastern Asia. It is a tall tree, bearing velvety fruits, which have large seeds. The plant is found in dense forests. It grows in India, in Assam. The oil expressed from the seed is a brownish yellow liquid or soft solid, with characteristic odour. It contains a number of unsaturated acids.
Chaulmoogra oil is used in the treatment of leprosy and other skin diseases. The unsaturated acids present in the oil are known to be strongly bactericidal towards the microorganisms of leprosy.
18. Cocaine (Cokeen):
The leaves of Erythroxylon coca Lam., belonging to the family Erythroxylacae, contains a bitter, aromatic alkaloid, cocaine, which is used as anaesthetic. The plant is a small tree or shrub, attaining a height of 5 m or so, and is native to Peru and Bolivia. Cultivation of the plant is quite extensive in South America and the leaves are commonly used there as a masticatory. The leaves are plucked when they become mature. About 100 kg of leaves yield 1 kg of the drug. The plant is cultivated to some extent in India.
Cocaine, besides being used as anaesthetic, is also used as a digestive and nervine tonic. Cocaine users have been found to develop resistance to physical as well as mental fatigue and they can continue to work for long periods without taking food or drink.
19. Abromine:
The alkaloid, abromine, is obtained from the roots and the bark of the plant, Abroma augusta Linn., belonging to the family, Sterculiaceae. The plant is a large bush with fibrous bark and irritant hairs. It is found to grow wild and is also cultivated in UP, Assam, Sikkim and Khasi hills.
The fresh sap of the root-bark, which is viscid, is considered to be a very good emmenagogue and uterine tonic. It is also prescribed in cases of neuralgic dysmenorrhoea.