Bitter glycosides: Gentian root

1. Bitter glycosides

2. • Bitter glycosides are a class of compounds that plays an important
role in the digestive process.
• Bitter drugs and bitter constituents are used since a very early
period as stomachic, febrifuges, and bitter tonics and in digestive
disturbances.
• The bitterness of food on the tongue plays a very important role
as the taste of bitter foods stimulates the appetite and triggers the
secretion of digestive juices in the stomach, which in turn
improves the break down of food.
• Bitters begin by stimulating the taste buds. This triggers off a
reflex nerve action which increases the flow of saliva and stomach
enzymes.

3. • Examples of bitter digestives are :
• Blessed Thistle,
• Barberry bark,
• Goldenseal,
• Dandelion,
• Hops flowers,
• Yellow dock, and Gentian root.
• Bitter drugs preparations should be taken before or during
meals otherwise they cause digestive disturbances like
diarrhoea, and pain in the stomach.

4. Gentian root
( BP, EP, BHP)

5. • Synonyms:
• Gentian root
• Yellow gentian root
• Bitter root
• Kutaki and Karu
• Pale Genetian;
• Radix Gentianae;
• Gentiana.
• Gall weed
• Bitter wart.
• Biological source:Gentian consists of the dried rhizome and root of
• Gentiana lutea L. and Gentiana kurroo
• Family:
• Gentianaceae

6. Geographical source:
• It is found in Central and Southern Europe, Asia, Turkey. It is
also grown on Vosges Mountains, Yugoslavia and Jura.
• It is perennial herbaceous tree which is found to be native to
the hilly zones in Central and Southern Europe and Asia.
• Gentiana kurroo native of north western Himalayas region.
• Gentiana lutea central Europe.

7. Cultivation Collection and preparation:
• G. lutea requires a moist soil , good drainage and a suitable soil
consisting of loamy.
• Seeds are slow to germination ,seedlings frequently taking
several years to appear.
• It is perennial herbaceous tree.
• The drug is collected from a 2- 5 years old plant in the autumn.
• Turf is stripped and the rhizomes are dug up. After it is washed
and cut into suitable length, the drug is dried, first in the open air
and then in sheds.

8. Preparation
• The freshly sliced pieces of roots and rhizomes generally appear
white in colour and do not have any odour.
• However, during the process of gradual drying in small heaps at a
controlled temperature of 50-60oC fermentation commences
which eventually turns them into dark or yellow coloured product
that have a characteristic odour.

9. Rhizome and roots

10. Description
• The description of root and rhizome of gentian are
summarised below:

11. Microscopical characters:
• 1. Periderm:
• (i) Cork: 4-5 layers, thin walled rectangular cells and orange brown in
colour.
• (ii) Phellogen and Phelloderm: Not distinguishable through a few layers
of thick walled tangentially elongated parenchyma is seen immediately
below cork.
• 2. Cortex:
• Thin zone of tangentially elongated thick walled parenchymatous cells
containing oil globules, few starch grains and minute acicular raphides
• 3. Secondary phloem:
• Relatively a wider zone made of tangentially elongated thick walled
parenchymatous cells containing oil globules, few starch grains and
minute acicular raphides. Sieve elements are distinct and phloem fibres
are entirely absent.

12. • 4. Cambium:
• Distinct and represented by a yellow ring of 3 to 5 layers of thin walled,
small rectangular cells.
• 5. Secondary xylem:
• Forms the bulk of the root it consists of largely parenchyma, vessels
and medullary rays. The vessels are occasionally isolated but mostly in
groups. Groups of vessels appear more towards the cambium. Way,
yellowish bands of medullary rays, through indistinct, transverse the
xylem parenchyma and at time extend up to the cortex. Wood fibres
absent. Xylem parenchyma and medullary ray cells also contain oil
globules, few starch grains and minute acicular raphides.

17. Chemical constituents:
• 1. Bitter principle: Gentiopicrin, Amaragentin. Gentian contains a
large number of bitter glycosides, which include gentiopicrin,
gentiamarin, gentiin, etc
• 2. Alkaloids: Gentianine.
• 3. Xanthine derivatives: Gentisin, Gentioside.
• 4. Sugar: Gentiobiose and gentianose. It also contains free sugars,
gentianose and sucrose, enzymes,
• 5. Gentisic acid. 7. Pectin and calcium oxalate
• 6. Tannins

18. Uses:
• Gentian root has a long history of use as an herbal bitter in the treatment of digestive
disorders.
• It contains some of the most bitter compounds known and is used as a scientific basis for
measuring bitterness.
• It is useful in states of exhaustion from chronic disease and in all cases of debility,
weakness of the digestive system and lack of appetite.
• It is one of the best strengthened of the human system, stimulating the liver, gall bladder
and digestive system, and is an excellent tonic to combine with a purgative in order to
prevent its debilitating effects.
• It is also used as anthelmintic, anti-inflammatory, antiseptic, bitter tonic, cholagogue,
emmenagogue, and febrifuge, refrigerant and stomachic.
• It is taken internally in the treatment of liver complaints, indigestion, gastric infections and
anorexia. It should not be prescribed for patients with gastric or duodenal ulcers.

20. Powder analysis of Gentian:
1. Organoleptic characters:
Colour:
(i) Tawny- brown powder.
(ii) Taste: Bitter.
(iii) Odour: Aromatic.
2. Vessels:
They are well developed wide vessels with reticulate thickening.
3. Vascular elements:
They are characteristic pattern of design of the run- way of the vascular elements.
4. Parenchyma:
They thick walled cells containing oil globules and minute acicular raphides
5. Starch grains:
They are small, simple and not many.