Chirayita, Kirayata (Swertia chirayita) Part 1
Chirayita,
Kiraytatikta (Swertia chirayita) Part 1
Introduction
Chirayita, a popular
medicinal plant displays pleiotropic pharmacological activity. It is indigenous
to India. The ethnomedicinal herb is known mostly for its bitter taste caused
by the presence of different bioactive compounds that are associated with human
health-welfare. The medicinal usage of Chirayita is well-documented in Indian
pharmaceutical codex, the British and the American pharmacopoeias and in
different traditional medicines such as Ayurveda, Unani, Siddha and other
conventional medical systems.
As this bitter plant is
found mostly in jungles, especially jungles of mountainous areas; the plant is
known as Kirata-tikta. Because the herb bears some semblance of Neem and is
found in Nepal it is also known as Neem Nepali. The plant was introduced in
Europe in 1839 and has been widely used since then.
The high usage mostly
of its underground tissues, illegal over destruction from its habitat, narrow
geographic occurrence and inherent problems of seed viability and seed
germination has resulted in drastic reduction of its population. The plant is
now on the verge of extinction. Alternative approaches for propagation and
conservation are urgently required to avoid the possible extinction of this
species.
The increasing national
and international demand for this medicinally valuable plant led to
unscrupulous collection from the wild and adulteration of supplies. Swertia angustifolia Linn, Swertia pulchella Linn, Swertia decussate Linn and Swertia corymbosa Benth are less bitter
and are used as adulterants. Swertia
chinensis Franchet a smaller herb is a better substitute for Swertia chirayita.
Providing high-quality
genetically uniform clones for sustainable use and thereby saving the genetic
diversity of this species is important. In this regard, micropropagation,
synthetic seed production and hairy root technology can play a significant role
in holistic conservation strategy. [1], [2], [3], [4]
Fortunately according
to the new International Union for Conservation of Nature and Natural resources
(IUCN) criteria, Swertia chirayita
has been categorized as critically endangered species. Hence the plant Swertia chirayita has been prioritized
by the National Medicinal Plant Board of Government of India for conservation
and cultivation in Uttranchal, emphasizing the need to develop agro-technology
packages. [5], [6]
History
Kirayat has long been
known to be a valuable medicinal plant to Ayurvedic scientists. It is mentioned
by Sushruta under the name ‘Kirata-tikta’ which means the bitter plant of the
‘Kiratas’, an outcast race of mountaineers in the Himalayas. It is also
popularly known as ‘Anarya-tikta’, “the bitter plant of non-Aryans”. The herb
is much esteemed by Ayurvedic physiacians on account of its pleotropic
pharmacological activities.
Mahomedan writers on
Indian drugs have identified Kirayata (Chiretta)
with ‘Kasab-ed-darira’ of Arabs and ‘Sweet flag’ (Calamus aromaticus/Acorus calamus)
of Dioscorides, a Greek physician, botanist and pharmacologist.
In Europe the plant was
first described by Roxburgh (also known as Rosbroch), a civil parish under the
name Gentiana chirayita in 1814. In England the plant began to attract
attention about the year 1829. In 1839 it was introduced into the Edinburgh
Pharmacopoeia. It is now official in the British and Indian Pharmacopoeias, and
is generally accepted as a valuable bitter tonic. [7]
Other Names
Taxonomic Name: Swertia
chirata,
Swertia chirata Buch
Sanskrit:
Kirata,
Kirataka, Kirat-tikta, Kirat-tiktaka, Chirayita,
Anaryatikta, Bhunimba and many more
English:
Chiretta
Arabic:
Qusa
Buzzaraioh
Assamese:
Chirata
Bengali: Chirata, Chireta
Burma: Se Khag
Farsi:
Nainihaabandi
Gujarati:
Kariyatu,
Kariyatun
Hindi: Chirayita
Kannada: Chirata, Chirayat, Kaddi, Kiratatikta,
Nilabevu, Nalebevu,
Kashmiri: Lose
Chiraita
Malayalam: Nilavipaa, Nilaveppa
Marathi:
Kirait
Nepali:
Cherota
Oriya
(Orissa): Chireita, Chirito
Patna:
Cherayata
Punjabi:
Charatin,
Chiraita
Tamil: Nilavembu
Telugu: Nilavemu
Urdu:
Chiraita,
Cheriyota [8], [9], [10], [11]
Taxonomic Classification
Genus: Swertia
Species: chirata [12]
Kingdom: Plante
Family: Gentianaceae
Division: Angiosperm
Subdivision: Dicotyledon
Class: Gamopetallae
Subclass: Bicarpellotai
Order: Gentionale
Scientific classification
Kingdom: Plantae
Clade: Angiosperm
Clade: Eudicots
Clade: Asterids
Order: Gentiales
Family: Gentianaceae
Subtribe: Swertinae
Genus: Swertia
Species: chitata [13]
Varieties of Chirayita
Narhari Pandit quoted two
varieties viz. Kiratatikta and Naipala Nimba. The latter also appears as
Himalayan species.
Kaalamegha-Kalmegh (Andographis panuculata) is often confused with Kirayata.
In Kerala Kaalamegha-Kalmegh (Andographis panuculata) Ness and
Bruhatee (Solanum indicum) Linn are
used in place of Kirata-tikta.
Commonly
three types of Kirata-tikta are recognized.
1) Swertia
chirata- Kirata-tikta
2) Swertia
angustifolia- Meetha Chirayita (Sweet or less bitter variety)
3) Swertia
alata [14]
Tibetan
Medicine recognizes three varieties of Tig
ta:
1) Indian Swertia, Swertia chirata, Swertia racemosa (Rgya tig)
2) Nepalese Swertia, Swertia ciliate (Bal tig)
3) Tibetan Swertia, Swertia spp (Bod tig) [15], [16]
Substitutes
for Chirayita
If Chirayita (Swertia chirata) is not available, Ayurveda recommends use of
functionally similar herbs of Gentianaceae family as substitutes for medicinal
purpose. Here they are:
1.
Swertia purpurascens Wall
2.
Swertia decussata Nimbo
3.
Swertia chinensis Franchet
4.
Swertia paniculata Wall.
5.
Swertia perennis Linn
6.
Swertia lawii Burkill
7.
Swertia affinis C. B. Clarke
8.
Exacum bicolor Roxb
9.
Exacum tetragonum Roxb
10. Erythraea
roxburghii G. Don
11. Enicostemma
littorale Blume [17]
Geographical
Distribution
Chirayita also known as
Indian gentian is a robust annual herb. It is distributed from Uttar Pradesh,
Uttarakhanda, Kashmir and Himachal Pradesh to the temperate Himalayas from the
height of 4 thousand to 10 thousand feet. It is also found in Bhutan and Kosi
hills. Nepal is the prime cultivator country of Chirayita. Chirayita is now
cultivated in hills of Madhya Pradesh and South India. The plant prefers sandy,
loamy as well as clay soils especially along the streams or marshlands. The
plant thrives and flourishes well in neutral, acidic as well as alkaline soils.
The plant can grow well in shade or somewhat woodland conditions and needs
humid or damp soil. The plant actually develops best in areas where summers are
cool. It is a hardy plant as it can withstand temperatures as low as -150 C and up to 100 C.
The plants bloom between September and October when the soil contains plenty of
humus. [18], [19]
Plant Morphology
Macroscopic Characteristics
Plant
Chirayita
plant Chirayita young sapling
Chirayita
is an erect, annual, branched herb growing up to 1.5 m in height [20]
Root
Chirayita root
The
root is simple, tapering, stout, short, 7 cm long and 2 to 3 cm thick [21]
Stem
Chirayita stem
Chirayita dried stem
The stem is erect, robust, branching, about
2-3 feet long, orange to brown or purplish in color, cylindrical below but four
angled upwards, with a prominent decurrent line at each angle, containing a large
pith [22], [23]
Leaves
Chirayita leaves
Leaves
are opposite, decussate, sessile, broadly ovate or lanceolate, 3.5 to 10 cm
long and 1.5 to 4.0 cm broad, obtuse or cordate at base acute at apex margins
entire, usually with 3 to 7 lateral veins; basal leaves 6.40 to 17.50 cm long
and 2.5 to 6.60 broad, having 7 veins, middle leaves 4.00 to 19.70 cm long and
2.30 to 4.60 cm broad having 5 veins, top leaves 2.5 to 7.40 cm long and 1.00
to 3.00 cm broad having 5 to 7 veins. [24], [25], [26]
Flowers
Chirayita
inflorescence
Inflorescence
Flowering
in chirayita is in the form of solitary axillary or axillary and terminal
clusters of 3-5 flowers; numerous small, axillary, opposite, lax chymes
arranged as small branches (the inflorescence). The inflorescence of chirayita
is a large panicle, 2feet long.
Chirayita flowers
Flowers
Flowers
small, stalked, yellowish-green outside, purple inside, tetramerous, drooping
or erect, bracteates, pedicellate, complete, bisexual, actinomorphic,
hypogynous, 9.2 to 11.5 mm in diameter, 8 to 9.3 mm in length, pedicel 4.9 to
5.7 mm long.
Flower
tube is twice as long as the sepal-cup, divided near the base into four ovate
lance like segments
Calyx:
Sepals are four gamosepalous, lanceolate, smaller than corolla, elongated at
capsule maturation stage, sepal tip acute, green, 5.3 to 6.1 long and 1. 0 to
2.0 mm
Corolla:
Petals four, gamopetalous, ovate, greenish yellow tinged with purple at
margines. The upper surface of the petal has a pair of green, honey secreting
glands (nectaries) covered with oblong scales and ending as fringes, fringed
with hairs, hairs extending up to half the length of corolla tube; petals 6.2 to
7.0 mm long and 2.7 to 3.2 mm broad.
Androecium:
Stamens four, epipetalous, alternipetalous, polyandrous, bithecous, inferior.
Stamens 4.9 to 5.7 mm long; filament 3.8 to 4.2 mm long; anther 1.0 to 1.4 mm
long
Gynaecium:
Bicapillary, syncarpous, unilocular, parietal placentation, stigma bifid, style
slender, superior, 1.2 to 2.0 mm long; no of carpels 2; ovary 2.6 to 3.0 mm
long; pistil 3.8 to 5.0 mm long [27], [28], [29]
Fruit
Fruit of Chirayita
Fruit
a capsule, ovoid or ellipsoid or egg shaped, many sided, haired, sharp, pointed
and pink in color, 6 mm in diameter. [30], [31], [32]
Seeds
Seeds
numerous, minute, globose, brownish, smooth and many angled; testa closed,
oveolate. [33]
Microscopic characteristics (A)
Stem:
The
transverse section (TS) of a young stem of Chirayita (Swertia chirata) reveals a single layered epidermis, with
tangentially elongated cubical cells measuring 14-25-32 x 11-18-25 microns. The
epidermis is covered externally by a striated cuticle. The epidermis does not
rupture even in older stages when considerable amount of secondary growth has
taken place.
At
the corners of the young stem, there are four outgrowths, the ribs, measuring
182-208-260 (unit not clarified) in length. Two of them are parallel to each
other. In older stem, these become less conspicuous and finally disappear
towards the basal part of the stem.
The
sub-epidermal collenchyma is 2 to3 layered followed by a wide zone of 8 to 10
layered parenchyma. The cells of collenchymas show angular thickenings. They
measure 21-28-35 x 18-24-30 (unit not clarified) in cross section and fill
almost the whole space within the ribs. The cells of the parenchyma measuring
22-30-50 x 14-20-32 (unit not clarified) are somewhat elongated tangentially
with marked intercellular spaces.
In
mature stems the endodermis is distinct with 2 to 3 radial walls. The pericycle
is indistinct. On both sides of xylem, phloem is present. The phloem consists
of phloem parenchyma, sieve tubes and companion cells. The internal phloem is
more developed than the outer phloem. Between the phloem and xylem there is a
thin layer of cambium. The pericycle is indistinct.
The
transverse section of the rootlets show a single layered epidermis consisting
of arched cells measuring 22-30-38 x 13-19-30 (unit not clarified), eight
groups of xylem (octarch xylem). The parenchymatous cortex has 3 to 6 layers of
thin-walled cells, the endodermis being the innermost. The endodermal cells
show 2 to 4 radial walls.
During
the secondary growth, the cortical cells do not rupture in as much as they
divide radially and thus meet the pressure of the secondary tissue developing
within. When the growth advances further, epidermal and cortical tissues
rupture leaving the endodermal cells which become prominent by the possession
of 3 to 4 radial walls. The pericycle is thin walled.
In
early stages the xylem has abundant parenchyma with a few scattered, annular
and spiral elements. In later stages the parenchymatous primary xylem is
surrounded by secondary xylem composed of thick-walled tracheids, a few xylem
vessels and fibers. The vessels are mostly isodiametric. The tracheids are
mostly cylindrical and the fibers are thick-walled and lignified. In the root
calcium oxalate crystals are absent.
Leaf:
In
the leaf, the mesophyll is undifferentiated. The epidermis is covered by
striated cuticle and is devoid of any trichome. The upper epidermis consists of
a single layer of tangentially elongated cells with walls perpendicular to
surface (anticlinal walls). In surface view the epidermal cells appear sinuous,
measuring 38-64-95 x 38-57-75 (unit not clarified) on the upper surface and
36-52-78 x 29-47-65 (unit not clarified) on the lower surface. Stomata are
present on the lower surface of the leaf only. The stomata are surrounded by
three subsidiary cells of which one is smaller than the other two.
The
mesophyll consists of 3 to 6 layers of loosely arranged parenchymatous cells.
They are isodiametric or somewhat elongated in radial direction. The structure
of the lamina is similar to that at the margin.
Midrib:
The
regions midrib and lamina are very distinct. The epidermis consists of a single
layer of cells which are cubical measuring 22-36-44 x 24-42-50 (units not
clarified), covered externally by thin cuticle.
Below
epidermis is a wide zone of cortex, composed of a single layer of collenchyma
showing angular thickenings and a wide zone of parenchyma. The parenchymatous
cells are thin-walled, isodiametric, measuring 23-36-45-57 (units not
clarified) in diameter. There are marked intercellular spaces in the cortical
parenchyma. The cells towards the vascular tissue are small measuring 14-19-24
(units not clarified). In the vascular region phloem surrounds central
xylem.
[Note:
The microscopic features of Swertia
chirata and Swertia alata are
similar. As Swertia alata is easily
available, botanists describe the microscopic features of Swertia alata. Here I compare the microscopic features of both the
species.]
Stem:
Swertia chirata
1.
Acinular crystals of calcium oxalate in
the cortical cells
Swertia alata
1a.
Calcium oxalate crystals absent in the whole plant
Swertia chirata
2.
Interxylary region of phloem is narrow
Swertia alata
2a.
Interxylary region of region of phloem is wide.
Swertia chirata
3.
In older stem, cavities appear in the premedullary zone due to disintegration
of the cells of the pith
Swertia alata
3a.
Cavities do not appear in older stem and the pith remains intact.
Swertia chirata
4.
Oil globules present in the cortical cells.
Swertia alata
4a.
Oil globules are absent
Leaf:
Swertia chirata
5.
The mesophill is differentiated
Swertia alata
5a.
The mesophill is undifferentiated
Swertia chirata
6. The upper epidermal cells show reticulate
thickening
Swertia alata
6a.
No reticulate thickening in the upper epidermal cells
Swertia chirata
7.
In the surface view, the upper epidermal cells have straight walls
Swertia alata
7a.
The upper epidermal cells have sinuous walls
Root:
8.
Internal phloem is present
Swertia alata
8a.
Internal phloem is absent [33]
Microscopic characteristics (B)
Root:
Transverse
section of root shows 2 to 4 layers of cork, secondary cortex represented by 4
to 12 layers of thick-walled parenchymatous cells, some showing radial wall
formation, tangentially elongated with sinuous walls; secondary phloem composed
of thin-walled strands of sieve tubes, companion cells and phloem parenchyma;
secondary xylem composed of vessels, tracheids and xylem fibres, all elements
lignified and thick-walled in older roots; centre of woods more or less spongy and
hollow in most cases, outer woody ring remaining strongly lignified, vessels
show scalariform thickening and also simple and bordered pits, tracheids
similar in thickening as the vessels, fibres have simple pits, mucilage present
in secondary cortical cells, minute acicular crystals present in abundance in
secondary cortex and phloem region, resin also present as dark brown mass in
secondary cortex cells.
Stem:
Transverse
section of stem shows single layered epidermis, externally covered with a thick
striated cuticle present in young stem, epidermis remains intact but cells
flattened and tangentially elongated in older stem; four ribs also consist of
epidermis and parenchymatous cortical cells, endodermis distinct, showing
anticlinal or periclinal walls, followed by single layered pericycle consisting
of single thin walled cells; stem posses amphiphloic siphonostele, external
phloem represented by usual elements; cambium between external phloem and xylem
composed of a thin strip of tangentially elongated cells; internal phloem
similar in structure as that of external phloem excepting that sieve tube
strand is more widely separated; xylem continuous and composed mostly of
tracheids, a few xylem vessels present singly or rarely in groups of two while
tracheids and fibres present in abundance, vessels and fibre tracheids have
mostly simple and bordered pits and fibres with simple pits on the walls;
medullary rays absent; central part of the stem occupied by pith consisting of
rounded and isodiametric cells with prominent intercellular spaces; mucilage
present in cortical cells minute acicular cells also present in abundance,
resin present as dark brown mass in some cortical cells along with oil
droplets.
Leaf:
Transverse
section of leaf shows very little differentiation of mesophyll tissues;
epidermis single layered covered with thick striated cuticle, more strongly
developed on the upper surface than on the lower surface; stomata of anisocytic
type; palisade tissue single layered; cells at places become wider and less
elongated particularly in bigger veins; spongy mesophyll represented by 4 to 7
layers of somewhat loosely arranged, tangentially elongated cells; some
epidermal cells prominently arched outside at the margin; mucilage present in
epidermal and mesophyll cells while minute acicular crystals also present in
abundance in mesophyll cells; in leaf parenchyma oil droplets also present. [33, B]
Parts used
Whole
plant
1.
Vijay Kumar et al, A Review of Swertia chirayita (Gentianaceae) as a
Traditional Medicinal Plant, Front Pharmacol, 2015; 6: 308
2.
https://www.planetayurveda.com/library/Kiratatikta-swertia-chirata/
3.
K. P. Sampath Kumar et al, Swertia chirata: A traditional herb and its
medicinal uses, J. Chem. Pharm. Res, 2010, 2(1): 262-266
4.
http://www.biologydiscussion.com/botany/pharmacognosy/chirata-decsription-preperation-and-uses/42940
5. Anon, Biodiversity Conservation
Prioritization Project, Conservation assessment and management plan (CAMP) for
endemic medicinal plants in India. CIMAP, Lucknow, 1997
6.
Convention on International Trade in Endangered Species of Wild Fauna and Flora
(CITES). Official documents: appendices I, II and III.
11.
https://www.ayurvitewellness.com/2954/kiratatikta-swertia-chirata/
17. Prof. K. C. Chunekar, Bhavprakasha
Nighantu, Chaukhambha Bharati Academy Varanasi, edited by Dr. G. S. Pandey,
Reprint: 2015, Page 70
18.
https://www.planetayurveda.com/library/kiratatikta-swertia-chirata/
20. Vikaspedia.in
21. https://www.aimilpharmaceuticals.com/herbs/chirayita/
22. vikaspedia.in
23. https://www.aimilpharmaceuticals.com/herbs/chirayita/
24. Aruna Mehta, Comparative
morphological Studies of some Swertia Species, Journal of Pharmacognosy and
Phytochemistry 2017; 6(1): 482-487
25. https://echarak.in
26. http://www.bsienvis.nic.in/CITES/Swertia%20chirayita.pdf
27. https://www.aimilpharmaceuticals.com/herbs/chirayita/
28. Aruna Mehta, Comparative
morphological Studies of some Swertia Species, Journal of Pharmacognosy and
Phytochemistry 2017; 6(1): 482-487
29. http://www.bsienvis.nic.in/CITES/Swertia%20chirayita.pdf
31. http://echarak.in
33. http://www.bsienvis.nic.in/CITES/Swertia%20chirayita.pdf
33 (B) http://www.ayurveda.hu/api/API-Vol-1.pdf
33 (B) http://www.ayurveda.hu/api/API-Vol-1.pdf
34. P. N. Natarajan and S. Prasad,
Pharmacological studies on Swertia Alata
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