Description
RAUWOLFIA
Synonym: Rauwolfia root, Sarpagandha
Biological source: It consists of the dried roots and rhizomes of Rauwolfia serpentina
Benth.
Family: Apocynaceae.
The name Rauwolfia serpentina has been taken from the name of scientist Dr. Rauwolf
and serpentina means snake like structured root.
Geographical source: Several species of plant is distributed in the tropical region of Asia, America and Africa. It is commercially cultivated in India (mainly in Uttar Pradesh, Bihar,
Orissa, Tamil Nadu, West Bengal, Karnataka, Maharashtra and Gujarat), Srilanka, Myanmar, Thailand and America.
Cultivation and collection: Rauwolfia develops luxuriantly under wide range of climatic
condition. It flourishes well in hot humid climate and grows quite well in shade. The clay
loamy soil with handsome amount of humus is most recommended. Good drainage is
supposed to be ideal for its cultivation. The acidic soil having pH 4 favors the growth of
plant. The other requirements for its cultivation are temperature 10-38 , Rainfall in the
range of 250-500 cm. Sandy soil makes the plant more susceptible towards diseases. The
propagation is mainly done by seeds, roots, cutting root stump etc. Propagation from seeds
is the method of choice. For this method, the seeds are sown in nursery beds in the month
of May-July. The developed seedlings are transplanted in the month of August-September
into open field at a distance of 15 to 30 cm. The fertilizers (like Ammonium sulphate, Urea)
and manures (generally bone meal) are supplied to the plants. The plants should be kept
free from weeds and they are uprooted when the plants are about 3 to 4 years old. The
roots are cut properly and washed with water to remove adhering impurities like sand or
other earthy matter. Then it is dried in air. About 5 kg of seeds is sufficient to cover one
hectare area. The average yield is about 1200 kg/ hectare but the yield can vary with type of
soil, climatic condition and age of plant.
Fig. 2.4: Rauwolfia plant and their roots
Macroscopical characters
Colour : Greyish yellow to brown (root bark) and pale yellow (wood).
Odour : Odorless
Taste : Bitter
Size : 10-80cm in length and 1-3cm in diameter.
Shape : Roots are sub-cylindrical, slightly tapered, tortuous.
Fracture : Short and irregular.
Chemical constituents
Rauwolfia contains at least 30 indole alkaloids. The total alkaloidal range is in 0.7-3
percent (depends upon the source). Alkaloids are concentrated mostly in the base of the
root and can be classified into:
1. Indole alkaloid
2. Indoline alkaloid
3. Indolenine alkaloid
4. Oxyindole alkaloid
5. Pseudo indoxyl alkaloid
Reserpine is the main alkaloid in Rauwolfia. It also contains oleo resin, phytosterol, fatty
acids, alcohols and sugars. The other alkaloids are Ajmaline, Ajmalicine, Rauwolfinine,
Rescinnamine, reserpinine, yohimbine, serpentine, serpentinine. Reserpine alkaloid is
colorimetrically determined by the reaction in between acidic solution of alkaloid and
sodium nitrite. Structure of Rauwolfia alkaloids
Chemical Test:
1. When fractured surface is treated with concentrated nitric acid, a red coloration
observed.
2. When reserpine is treated with solution of vanillin in acetic acid, it shows violet red colouration.
Uses:
It has antihypentensive activity. The most clinically important compounds are reserpine,
rescinnamine and ajmalicine. Reserpine depletes the catecholamines stored at nerve endings
and lowers the blood pressure. The drug is used in mild anxiety condition and
neuropsychiatric disorders (due to its tranquillising effect). Deserpidine and Rescinnamine
used as antihypertensive. Deserpidine shows very less side effects and rescinnamine causes
mental depression in higher dose concentration. Ajmalicine uses in the treatment of
circulatory diseases and in cerebral blood flows obstruction.
Allied Drugs:
R. tetraphylla
R. nitida
R. densiflora
R. vomitoria