The following points highlight the two important medicinal plant grows in India. The medicinal plant are: 1. Quinine 2. Sarpagandha.
Medicinal Plant # 1. Quinine (Cinchona):
Quinine is a evergreen shrubs or trees with bitter bark. Leaves opposite, stipulate; stipules interpetiolar, caducous. Flowers in terminal panicles, hermaphrodite, regular, pentamerous, epigynous. Calyx 5 – toothed, pubescent, persistent.
Corolla tubular, 5-lobed, pubescent outside, fringed with soft hairs on the margin, valvate; ovary 2-celled, inferior, with many ovules in each cell; style slender, bifid; stigma papillose. Capsule 2 valved, dehiscing septicidally from base. Seeds many, small, broadly winged, thin and compressed.
The genus consists of about 65 species growing in the forests of Andes Mts. of S. America. The bitter bark contains the alkaloid quinine which is a specific merely in malarial fever.
Important species for the alkaloid content are C.OFFICINALIS Linn., C. SUCCIRUBRA Pav. ex Klotz, C. CALISAYA Wedd. and C. LEDGERIANA Moens. the genus is so named in honour of Countess Cinchon who introduced this important drug plant to the physicians of Europe and was instrumental for starting plantations of different species of the genus on commercial scale.
The diagnostic characters of the above 4 species are:
C.OFFICINALIS – up to 10 m. high; leaves 10-12 cm. long, elliptic; flowers 2 cm. long.
C.SUCCIRUBRA – up to 12 m. high or taller; leaves 8-15 cm. long, ovate; fls. 1.5-2 cm long.
C.CALISAYA — 12 m. or more high; leaves 8 – 20 cm. oblong; flowers 1 – 2 cm.
C. LEDGERIANA — smaller plants; leaves 5 -10 cm. lanceolate; flowers 1 cm. long.
The last species is considered by some to be a variety of C. calisaya.
CINCHONA plants thrive in a damp hot climate. Tropical and subtropical regions with a temperature ranging from 60° – 75° F and an annual rainfall of 250 – 325 mm 1100 – 150 in.), well distributed throughout the year are well suited for growing CINCHONA. The soil should be well drained, rich in organic matters, acidic and with a Nitrogen level of 8%. The plants should be sheltered from wind. They are not frost-resistant.
Cinchona plants are propagated by seeds. Seeds have short viability. Fresh seeds are therefore sown in seed beds situated on sloping grounds. Size of seed beds are usually 3 X 1V2 m. These are covered by thatched roofs.
The seeds are thickly scattered on a layer of a mixture of leaf-mould and sand and covered by fine sand. The seed beds are lightly watered. Germination takes place in 3 – 6 weeks. Seedlings when about 3 cm. high and have 2 leaves are then transplanted in nursery beds with a thicker layer of leaf-mould and sand.
No other organic or artificial manure is applied. Spacing of about 10 cm. is permitted in a row and between 2’rows. When the seedlings are of 14-18 months old these are transplanted in plantation-fields, usually in early monsoon.
The seedlings are 50 – 70 cm. high at that time. The spacing in the plantation is 2 X 2 m. or less and shade trees are planted at intervals of 7 m. Stable-manure is applied as this increases the quinine content of the bark.
Harvesting starts from the 5th year onwards when annual thinning is necessary. The alkaloid content is maximum in trees of 10 years old or older. The bark is easily separated. Often tapping makes it more easy. Bark is collected from the basal part up to a height of 1 mtr.
The root bark is also equally rich in alkaloid content and is collected when the tree is felled. Harvested bark is dried slowly in shade. In rainy season artificial heat may be applied but the bark should not be exposed to a temperature over 175°F.
For the manufacture of the drug the bark is ground to a fine powder. The powder is mixed with l/3rd of its weight of sifted slaked lime and a 5% aqueous solution of caustic soda. The mixture is extracted with high boiling kerosine. Extract is shaken with sufficient hot dilute sulphuric acid and precipitation of quinine sulphate is obtained.
In addition to quinine the bark also contains quinidine, cinchonine and cinchonidine. The quinine in addition to its antimalarial property is an insecticide. The bark can also be used in tanning.
The introduction of Cinchona into India has a history behind it. To meet the great demand from all over the world Cinchona forests were in the verge of extinction in their home and civilized world were thinking of starting plantations at suitable places in different countries.
The Dutch Government introduced these plants in Java and were successful in cultivating Cinchona in that island. Dr. Royle suggested its introduction in India as early as 1852 and sent several reports to the secretary of State for India.
T. Anderson, the then Superintendent of Botanic Garden in Sibpur also supported Royle and suggested several places for cultivation of Cinchona. Orders were received to that effect and cultivation was started in 1861 in Sikkim and the Nilgiri hills.
In 1867 Cinchona — cultivation was started but later abandoned in the Khasi hills. In Kangra and different other parts of N.W. India plantations were started but later abandoned for various reasons. Plantation of Cinchona was started in Bhutan but was not found profitable.
Several private plantations were started in S. India as early as 1862 but did not prove profitable. At present it is cultivated in the plantations at Mungpoo in the Darjeeling District and the plantation is maintained by the W. Bengal government.
Medicinal Plant # 2. Sarpagandha (Rauvolfia Serpentina):
Sarpagandha is glabrous undershrub, up to a mtr. high. Leaves are ternately whorled, elliptic — laceolate, acuminate, entire, smooth and shinning, deep green above and pale beneath, 4 – 18 cm. long. Inflorescence terminal cymose umbelliform panicle, usually many flowered.
Flowers bisexual, actinomorphic, hypogynous, bracteate with small subulate bracts. Calyx 5 – fid, glabrous, bright red; segments lanceolate, 2 mm. long, imbricate. Corolla tubular 1-1.5 cm. long, rose or pink; tube slender, swollen at middle, hairy at the throat, rarely curved; lobes 5, 3 – 4 mm. long, elliptic, rounded at apex, imbricate.
Stamens 5, inserted in the dilated portion of the corolla-tube. A membranous cupular disc is present. Carpels 2, superior.style filiform; stigma with a broad calyptriform base, 2 – fid at the tip; ovules 2 in each carpel. Fruit a single or didymous drupe, 4 – 5 mm. in diam; purplish black when ripe.
The species is indigenous in India, Bangladesh, Burma, Ceylon and Malaysia. In India it is found in the mixed deciduous forests from the foot of the Himalayas to Kerala. It is no-where abundant but grows scattered in the fringe of the forests, in open jungles and village shrubberies.
It prefers a humid tropical climate but can stand a dry heat of about 110°F, for a short period. It grows well in gravelly or loamy soil with an annual rainfall of 1250 mm. to 3500 mm. provided the soil is well drained. The drug is collected from wild source but to meet the demand cultivation has been started on a small scale by the forest authorities in different states.
The plants are propagated from seeds which are swoon direct in the plantation in rows with spacing of 70-80 cm. in the rows and about 1 mtr. between the rows. The plants are ready for harvesting after 2 years. In collecting wild plants those with a stem of 1 cm. or more in diam. are gathered.
In R. serpentina the alkaloids are present in the root, more in the bark and less in the woody portions of the same. In other parts these are present in negligible quantities.
The alkaloids contained in the root of R. serpentina are several, the most important is he RESERPINE used to lower high blood pressure. Other alkaloids are: Reserpinine. terpentine, Serpentinine, Rauvolfinine, etc. All are useful in different ways. The crude drug, i.e. the root is exported every year and the quantity is about 150,000 kg.
Several other species of Rauvolfia grow wild in India and R. tetraphylla Linn, of the West Indies is naturalized in the coastal districts. R. tetraphylla contains similar alkaloids in the leaves and other parts but in less quantities. This differs from R. serpentina in having soft, emareld green leaves, 4 in a whorl and smaller white flowers.
Other Indian species of the genus are:
R. beddomei Hk.f. — S. India, R. decurva Hk.f. — S.India. R.densiflora Benth — Chasi hills and S. India, and R. micrantha Hk.f. — Malabar. All these species contain eserpine in small quantities and segregation of the alkaloid from these plants is not commercially profitable. Used as crude drug they do not yield the desired result.