A REVIEW ON VARIETIES OF ARKA - CALOTROPIS PROCERA (AITON) DRYAND. AND CALOTROPIS GIGANTEA (L.) DRYAND

Abstract

Herbal medicines have been used from the earliest times to the present day. The ethno-botanical pharmacology is as old as man himself. Herbal medicines exhibit a remarkable therapeutic diversity. Arka is a plant which has been used in several traditional medicines to treat a variety of diseases. Calotropis procera and Calotropis gigantea are two varieties of Arka described in Ayurveda by the name of Rakta Arka and Shveta Arka. Both have almost similar properties but C. procera is considered somewhat superior. In Ayurvedic texts also by the name of Arka, Acharyas mentioned Rakta Arka (Calotropis procera) because of having more medicinal properties than C. gigantea. This plant has been known to possess analgesic, antitumor, antihelmintic, antioxidant, hepatoprotective, antidiarrhoeal, anticonvulsant, antimicrobial, oestrogenic, antinociceptive, and antimalarial activity. [PUBLICATION ABSTRACT]

Headnote

Herbal medicines have been used from the earliest times to the present day. The ethno-botanical pharmacology is as old as man himself. Herbal medicines exhibit a remarkable therapeutic diversity. Arka is a plant which has been used in several traditional medicines to treat a variety of diseases. Calotropis procera and Calotropis gigantea are two varieties of Arka described in Ayurveda by the name of Rakta Arka and Shveta Arka. Both have almost similar properties but C. procera is considered somewhat superior. In Ayurvedic texts also by the name of Arka, Acharyas mentioned Rakta Arka (Calotropis procera) because of having more medicinal properties than C. gigantea. This plant has been known to possess analgesic, antitumor, antihelmintic, antioxidant, hepatoprotective, antidiarrhoeal, anticonvulsant, antimicrobial, oestrogenic, antinociceptive, and antimalarial activity.

KEY WORDS: Rakta Arka, Calotropis gigantia, Arka, antinociceptive.

INTRODUCTION:

Arka (Rakta Arkci) an important drug of Ayurveda is known since Vedic period. In the vedic literature Arkci leaves were used in the sacrifical rites (Sharma P.V., 2005). There are two common species of Calotropis, viz Calotropis gigantea (L.) Dryand nd C. procera (Aitón) Dryand described in the classical literature of Ayurveda by the name of Shveta Arka and Rakta Arka. Calotropis is a genus of plants that produce milky sap hence also commonly called milkweed. The latex of Calotropis procera is said to have a mercury- like effects on the human body, and is sometimes referred to as vegetable mercury and is used in place of mercury in aphrodisiacs. C. procera is used variously but sometimes leaves are fried in oil for medicinal purposes. Cattle often stay away from both the plant C. procera and C. gigantea because of their unpleasant taste and due to presence of Cardiac Glycosides in its sap. Root bark of C. procera has Digitalis like effect on the heart, but was earlier used as a substitute of Ipecacuanha. It is a poisonous plant; calotropin, a compound in the latex, is more toxic than strychnine.

The Calotropis Shrub that produces white or sometimes voilet flowers is called as Swetarka. This is a rare shrub. Flowers of Swetarka are considered to be favorite of Lord Shiva.

C. gigantea as indicated by its name it is much larger and coarse plant than C.procera. Hindus obtain Ganapati from the root of C. gigantea that sometimes takes the shape of Lord Ganesh. The root of C. gigantea shrub is invited on some auspicious day (in the Ravi- Pushya Nakshatra ) and carved into the form of Ganapati or Ganesh in some auspicious muhurta. Hindus believe that those who worship this idol of Ganesh enjoy the presence of Mahadevi Laxmi and Lord Shiva. Most recently C. gigantea is scientifically reported for several medicinal properties viz. the flowers are reported to possess analgesic activity, antimicrobial and cytotoxic activity. Leaves and aerial parts of the plant are reported for anti-diarrhoeal activity, anti-Candida activity and antibacterial activity, antioxidant activity. Roots are reported to contain anti-pyretic activity, cytotoxic activity. Although both varieties of Arka have almost similar properties yet C. procera is having comparatively more medicinal properties.

Sources of Arka

Raktaarka - mainly has two sources

Calotropis procera - smaller red flowers - (Chief source of Raktaarka in N. India).

Calotropis gigantea (red variety) - larger red flowers - (Chief source of Raktaarka in S. India) (Bodhi Nighantu, 2010)

Shwetaarka - mainly has only one source

Calotropis gigantea (White variety) - larger White flowers - (Chief source of Shwetaarka all over the country). (Bodhi Nighantu, 2010).

Most of the Nighantus (Ayurvedic Materia medica) have mentioned same properties of both. Arka (Sharma Ramprasad, 1990). Dalhana in commentary Of Susruta Samhita mentioned that by Arka we should take Rakta Arka. Rakta Arka is having more tikshnata (having more sharp in properties) compared to Shveta Arka (Vyas Shiv Kumar, 1986).

Habitat

Calotropis procera is native to northern Africa (i.e. Algeria, Egypt, Libya, Morocco, Eritrea, Ethiopia, Somalia, Sudan, Kenya, Tanzania, Uganda, Cameroon and Equatorial Guinea)

Calotropis gigantea (Crown flower) is a species of Calotropis native to Cambodia, Indonesia, Malaysia, Philippines, Thailand, Sri Lanka, India and China.

The second variety is of 2 types ie. C. gigantea (Red) & C. gigantea (White).

C. procera Grown in Punjab, Bihar, Mumbai. The white variety of Calotropis gigantea is indigenous to Rajasthan & Gujarat (which is taken as Shwetarka in Ayurveda)

The red variety of Calotropis gigantea is common in South India.

So the white variety of C. gigantea has been introduced into South India especially in temples for its sanctity, (but when scaned through the market samples in South India the root of this variety is hardly available) (Bodhi Nighantu, 2010)

Botanical Description:

Calotropis procera {Rakta Arka) is a soft- wooded, evergreen, perennial shrub grows up to height of 3-6 m. It has one or a few stems, few branches, and relatively few leaves, mostly concentrated near the growing tips. The bark is corky, furrowed, and light grey. A copious white sap flows whenever stems or leaves are cut. Giant milkweed has a very deep, stout taproot with few or no near-surface lateral roots. Giant milkweed roots reach up to depths of 1.7-3.0 m in Indian sandy desert soils (Sharma B.M., 1968). The opposite leaves are oblong-obovate to nearly orbicular, short- pointed to blunt at the apex and have very short petioles below a nearly clasping, heart-shaped base (Nadkarni A.K., 2000). The leaf blades are light to dark green with nearly white veins. (Rastogi RP, 1999). They are 7-18 cm long and 5-13 cm broad, slightly leathery, and have a fine coat of soft hairs that rub off. inflorescenence is panicale with purple corolla and erect lobes. (Anonymous, 2000). The flowers are umbelliform cymes that grow at or near the ends of twigs. Flowers are shallowly campanulate with five sepals that are 4-5 mm long, fleshy and variable in colour from white to pink, often spotted or tinged with purple. The fruits are inflated, obliquely ovoid follicles that split and invert when mature to release flat, brown seeds with a tuft of white hairs at one end Sodom's apple milkweed produces a simple, fleshy fruit in a grey-green inflated pod, containing numerous flat, brown seeds with tufts of long, white silky hair ('pappus') at one end (Howard, R.A., 1989)

C. gigantea is a large shrub or small tree, about 4-10 m tall. Its stem is erect, up to 20 cm in diameter. The leaves are broadly elliptical to oblong-obovate in shape, with the size of 9-20 cm χ 6-12.5 cm but subsessile. The cymes are 5-12.5 cm in diameter. The inflorescence stalk is 5-12 cm long, the stalk of an individual flower is 2.5-4 cm long. Sepal lobes are broadly egg-shaped with a size of 4-6 mm χ 2- 3 mm. Petal is 2.5-4 cm in diameter. It has clusters of waxy flowers that are either white or lavender in colour. Each flower consists of five pointed petals and a small, elegant "crown" rising from the centre, which holds the stamens. The plant has oval, light green leaves and milky stem. The petal lobes are broadly triangular measuring 10-15 mm χ 5-8 mm; they are pale lilac and cream coloured towards the tips. The outgrown like structure from the petal (corona) has 5 narrow fleshy scales, connected to and shorter than the staminal column, forming an upturned horn with 2 obtuse auricles on either side, cream coloured or lilac to purple, with a dense longitudinal dorsal row of short white hairs. The egg-shaped or boat-shaped fruits are mostly in pairs, inflated, 6.5-10 cm χ 3-5 cm. The flowers last long. Taxonomical comparison between C. procera & C. gigantea is given in Table. No 1.

The photosynthetic capacity of C. procera is higher than that of C. gigantea (Wilmer Tezara et al, 2011).

Properties of both arka according to Bhavprakash (Chunekar K.C., 2007)

Shveta Arka Pushpa-Vrishya (potent), Laghu (Light), Dipana (Appetizer), Pachna (Digestive), Arachi, Prasek (controls excessive salivation), Svasa Kasa hara (cures asthma and cough)

Rakta Arka: Madhara Tikta, krimi (removes worms) kushta (cures all type skin disease) kapha hara arsha (piles), visha (poison), raktapitta (haemophillia), gulma, sopha hara (removes inflammation).

Chemical compostion-

Calotropis procera plant latex contains the cardenolide, proceraenin, while the root bark contains benzoylinesolone and benzoylisolinelone. The leaves and stalk contain calotropin, and calotropagenin while the flower contains calotropenyl acetate, and multiflavenol and the latex contains uzarigenin, and terpenol ester (Yoganarasimhan SN, 2000). Chemical investigation of this plant has shown the presence of triterpenoids, calotropursenyl acetate and calopfriedelenyl, a norditerpenyl ester, calotropternyl ester oleanene triterpenes like calotropoleanyl ester, procerleanol A and ? (Ansari SH et al, 2001) and cardiac glycosides calotropogenin, calotropin, uscharin, calotoxin and calactin(Ahmed KKM et al., 2005). The plant also has been investigated for the presence of cardenolides (Seiber JN, 1982) and anthocyanins. Phytochemical investigation of the roots of Calotropis procera yields two new phytoconstituents, procerursenyl acetate and proceranol, together with the known compounds N-dotriacont-6-ene, glyceryl mono- oleolyl-2-phosphate, methyl myrisate, methyl behenate and glyceryl-1, 2-dicapriate-3- phosphate. In the leaves, mudarine is the principal active constituent as well as a bitter yellow acid, resin and 3 toxic glycosides calotropin, uscharin and calotoxin. The latex contains a powerful bacteriolytic enzyme, a very toxic glycoside calactin (the concentration of which is increased following insect or grasshopper attack as a defense mechanism), calotropin D I, calotropin D II, calotropin F I, calotropin F II and a non toxic protealytic enzyme calotropin (2-3%). This calotropin is more proteolytic than papain, and bromelain coagulates milk, digests meat, gelatin and casein. The whole plant of Calotropis gigantea contains a- and b- amyrin, teraxasterol, gigantin, giganteol. They are poisonous plants; calotropin, a compound in the latex, is more toxic than strychnine. Calotropin is similar in structure to two cardiac glycosides which are responsible for the cytotoxicity of Apocynum cannabinnm. Extracts from the flowers of Rakta Arka (C. procera) have shown strong cytotoxic activity in the patients of colorectal cancer. Quercetin-3-rutinoside is identified in the roots, stem, leaves, flowers and latex. Voruscharin is isolated from African plant. Cardenolides contents in leaf (2.04 mg/gm) and in latex (162.0 mg/g), mostly calotropagenin - derived cardenolides present from Calotropis gigantea, two triterpene esters - 3 methylbutanoates of amyrin and taraxasterol are isolated from latex of C. gigantea. calotropins Di and D2 had been isolated from C. gigantea (Pal and Sinha, 1980). The new oxiopregnane- oligoglycosides named Calotropis A and ? have been isolated from the root of C. gigantea and their chemical structure have been elucidated by chemical and spectroscopy methods (Kitagawa Isao, 1992). The cytotoxic principles of 'Akond mid' (Root of C. gigantea) cardenoloids glycosides, calotropin frugoside and 4-O-Beta-D- glucopyranosyl frugoside were obtained as the cytotoxic principles (Kiuchi, F., 1998). Gigantin is a chemical extracted only from C. gigantea.

Uses: All the parts, viz, root, stem, leaf and flowers of Calotropis are in common use in indigenous system of medicine. Rakta Arka (Ait.) R. Br., a wild growing plant of family Apocynaceae is well known for its medicinal properties. Different parts of this plant have been reported to exhibit anti-inflammatory, analgesic, and antioxidant properties. (Ahmed UAM, 2006). Important factors of the various parts of this plant have been widely reported. Latex has been used in leprosy, eczema, inflammation, cutaneous infections, syphilis, malarial and low hectic fevers and as abortifacient (Basu A, 1997). Rakta Arka latex demonstrated strong inhibitory effect on E. coli, S. aureus, S. pyogenes, S. pneumonia, fungus like Aspergillus niger and yeast Candida albicans. Efficacy of Rakta Arka in the treatment of S. typhi and S. paratyphi has been confirmed. C. giganteds latex which is highly poisonous is used as purgative. Also when thorn entered to foot after removing the thorn its milk applied to reduce the pain. Ethanol extract of stems of C. gigantea was reported for hepato-protective activity in male Wistar rats against carbon tetrachloride induced liver damage and showed marked hepato- protective results. Proteins present in the latex of C. gigantea are strongly proteolytic and responsible for procoagulant activity of C. gigantea (Rajesh R. 2005).

Leaves: In rheumatism, as an anti- inflammatory and antimicrobial. The leaves of Rakta Arka are said to be valuable as an antidote for snake bite, sinus fistula, rheumatism, mumps, burn injuries, and body pain. The leaves of Rakta Arka are also used to treat jaundice. In Egypt, the dried leaves are smoked in pipes for relieving cough. A decoction of the leaves is given to relieve cough. For whooping cough the leaves are boiled with Momordica charantia and the decoction is drank a glassful each time. Leaves of C. gigantea were reported to carry antioxidant activity. (Singh N., 2010)

Roots: As hepatoprotective agents against colds, coughs and elephantiasis, as an anti- inflammatory, analgesic, anti-malarial and antimicrobial. The root is also used in the treatment of venereal diseases like gonorrhea and syphilis. In these cases the root or root bark is fermented in honey and given to the patient to drink, reported that Rakta Arka has anti- HIV-1. It is therefore a plant of interest for the treatment of HIV-AIDS. (Remya Mohanraj, 2010) For poisonous snake bites, 2 to 4 leaves of C. gigantea plant is chewed well by the patient. Also fresh root of this plant are crushed well and applied well by rubbing firmly over the bitten area. The anti-pyretic activity of C. gigantea roots in water : ethanol (50 : 50) has been reported (Chitema et al, 2005). Anti- pyretic activity was studied by using yeast and TAB (Typhoid) vaccine induced pyrexia in Albino Swiss rats and rabbits.

Flower: As cytostatic, abortifacient, antimalarial, in asthma and piles and villagers in Bikaner district ingest almost all plant parts of Calotropis procera in various dietary combinations for malarial fevers and pyrexias. In small doses, powdered flowers of Calotropis gigantea are useful in the treatment of colds, coughs, asthma, catarrh, indigestion and loss of appetite (?. Κ. K. Mueen, 2005) The flowers are bitter, digestive, astringent, stomachic, anthelmintic, and tonic (Agharkar 1991; Warrier et al, 1996). The alcoholic extract of the flowers of C. gigantea was reported for analgesic activity in chemical and thermal models in mice (Pathak AK, 2007).

Latex: Spectrum of ocular toxicity following accidental inoculation of latex of Calotropis procera has been reported which leads to diminish vision (Samar Κ Basak, 2009). The latex also used to induce abortion, infanticide. Latex also has wound healing properties (Narendranalwaya, 2009). The anti- inflammatory property of the latex of Rakta Arka was studied on carrageenin- and formalin- induced rat paw oedema model. A single dose of the aqueous suspension of the dried latex was effective to a significant level against the acute inflammatory response. Dried latex and chloroform extract of roots has been reported to possess anti-inflammatory activity (Raman Sehgal, 2005), (Kumar VL, 1994).

Calotropis gigantea yields a durable fibre useful for ropes, carpets, fishing nets and sewing.

Adverse effects:

The adverse effects Calotropis procera consumption are reported to cause blisters, lesions and eruptions when taken by patients for the treatment of joint pains and gastrointestinal problems and ocular toxicity. Besides sometimes cardio-protective steroid also show toxicity. The preparations of Calotropis procera need to be used under the supervision of a trained medical practitioner (Lewis Nelson, 2007). Latex of C. gigantea causes irritation to mucosa. An unidentified allergen is found in the latex of C. gigantea.

CONCLUSION:

The World Health Organization has estimated more than 80% of the world's population in developing countries depends primarily on herbal medicines for their basic healthcare needs. In recent years, traditional uses of natural compounds, especially those of plant origin, have received much attention of the world as they are well known for their efficacy and are generally believed to be safe for human use. It is best to use the classical approach in the search for new molecules to manage a variety of diseases. A thorough review of the published literature on Calotropis procera and C. gigantea shows that it is a popular remedy in a variety of ethnic groups, as well as Ayurvedic and traditional practitioners for the treatment of a range of ailments. Researchers are exploring the therapeutic potential of Arka as it is likely to have more therapeutic properties than known. As in advanced researches on Calotropis procera has been proven to be a good medicine in case of HIV, breast cancer, syphilis etc. which are becoming challenging to our society.

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Cite this article:

Poonam, Gaurav Punia (2013), A REVIEW ON VARIETIES OF ARKA - CALOTROPIS PROCERA (AITON) DRYAND. AND CALOTROPIS GIGANTEA (L.) DRYAND., Global J Res. Med. Plants & Indigen. Med., Volume 2(5): 392-K)0

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