barahi :

Varahi consists of dried cut pieces of rhizome of Dioscorea bulbifera Linn. (Fam. Dioscoreacem), a large unarmed climber found throughout India ascending upto 1800 m in the Himalayas.

HISTORICAL AND MYTHOLOGICAL REVIEW:

The plant was first introduced to the New World during the slave trade, and subsequently transported to Florida in 1905 as a USDA sample sent for horticultural examination (Coursey 1967, Schultz 1993). The Florida horticulturist who received the samples quickly saw the potential danger this aggressive potential invader posed for the state.

Vigorous asexual reproduction via bulbils has facilitated the continued spread of this invasive vine throughout most of the state. Martinez (1993) reported that Dioscorea bulbifera had become "rampant on undeveloped land" around Tampa. By 1996, the plant had been reported from natural areas in 23 Florida counties (Langeland and Burks 1998). As of 2007, the Florida Exotic Pest Plant Council Early Detection and Mapping System indicates D. bulbifera now occurs in at least 46 (of 67) Florida counties.

In 1999, D. bulbifera was added to the Florida Department of Agriculture and Consumer Services Noxious Weed List, banning introcuction, possession, transport, or release of the species in Florida without a permit (Langeland 2001).

Taxonomical Classification

Kingdom: Plantae - Plants
Subkingdom: Streptophyta
Superdivision: Spermatophyta - Seed plants
Division: Magnoliophyta - Flowering plants
Class: Magnoliopsida - Dicotyledons
Family: Dioscoreaceae
Genus: Dioscorea
Species: Dioscorea bulbifera

Allied species:

Dioscorea alata or winged yam can easily be mistaken for air potato, D. bulbifera. Winged yam gets it name from its winged internodes, a characteristic feature of the species. Another difference between D. alata and D. bulbifera is the arrangement of the leaves. D. alata has opposite leaves as opposed to the alternate leaves of air potato. Winged yam grows to 30 feet, roughly half the length of the invasive species. This species of Dioscorea does not produce nearly as many bulbils as D. bulbifera. However, this species can also be considered invasive and problematic, but to a lesser extent than D. bulbifera. 

VERNACULAR NAMES

Sanskrit: Vaarahikanda, Pindalu
English: Shoebutton Air Potato Air Yam Bitter Yam
Hindi: Gaithi, Hoei Oepas, Karu Kunda, Karukanda, Kodikilangu, Ratalu, Ratula
Urdu: ہوا آلو
Telugu: Adavi Dumpa, Chedupaddudampa, Karu Kanda, Malaka Kayependalamu.
Bengali: Ban Alu, Rat Alu, Roth Alu.
Marathi: Kadu Kand, Mataru
Konkani: Kongadde
Oriya: PitaaAlu.
Gujarathi: - Dukkarkanda
Tamil: Kayavalli, Perumvalli kizangu
Malayalam: Kachil-kilangu, Kaavathu
Kannada: Tung-genasu
Punjabi: ਹਵਾਈ ਆਲੂ Havāī ālū
Sindhi: هوائي آلو
Arabic: البطاطا الهواء albitata alhawa
Spanish: ñame Criollo, ñame De Aire,, ñame De Gunda, ñame Volador, Papa Cimarrona, Papa De Aire.
Japanese: Kashuu Imo, Niga Kashuu.
Chinese: Shan ci gu, Ling yu shu, Huang yao, Shan ci gu.
French: Igname Bulbifère, Igname Pousse En L´air, Masako, Pomme En L´air, Pousse En L´air.
German: Brotwurzel, Kartoffelyam, Knollen-yam, Luft-Kartoffel, Luft-yams, Yamswurzel
Burma: Ah Lu Thi, Hpwut Sa Uu, Pat Sa Uu.
Nepal: Giitthaa (Gittha), Giitthe Tarul (Gitthe Tarul), Jada Bis, Van Tarul.
Persian: -سیب زمینی هوا
Sinhalese: -ගුවන් අර්තාපල් guvan artāpal
Greek: -πατάτα αέρος patáta aéros

Varities:

According to Kaiyadeva nighantu types of varahikanda are 1. Shabarakanda 2. Kharakanda 3. Snukchadopama 4. Kiri 5. Mulakamulabha 6. Shoukara 7. Vadavaanala

Definition

-The word “varaa” means sasya (plant) and “aahanti” is that which destroys whatever comes in its way. Varaha is an animal which destroys the plants in its way. kanda means tuber. Varahakanda is the tuber which is liked by the pigs.  

Synonyms

Synonyms in Ayurveda: keyura, svalpa, vitapa, kenduka, svadu kandala


Rasa: Katu Madhura Tikta
Guna: Laghu
Veerya: Ushna
Vipaka: Katu
Karma: Kaphahara Pittahara

Varahikanda (Dioscorea bulbifera Linn.) which possesses profound therapeutical potency attributed with Vrushya (Aphrodisiac), Balya (strength promoting), Rasayana (Rejuvinative) karmas

Cultivation:

A plant of the moist, lowland tropics. It grows best in areas where annual daytime temperatures are within the range 20 - 30°c, but can tolerate 12 - 38°c. It can be killed by temperatures of 9°c or lower. It prefers a mean annual rainfall in the range 1,200 - 2,600mm, but tolerates 900 - 4,000mm. It prefers a well-defined dry season of 2 - 3 months. This species is more tolerant than most other yams of temperatures below 25°c
For best yields, this species requires a deep, well-drained, sandy loam that is not liable to water-logging[]. Prefers a pH in the range 6 - 6.7, tolerating 5.3 - 8
Daylengths of more than 12 hours are preferred during the early growing season since this encourages vegetative growth; daylengths of less than 12 hours towards the end of the growing season will encourage tuber formation and development.
The bulbils are produced in 5 - 6 months from planting, though some forms can produce a crop in as little as 3 months[]. Average yields of the bulbs are in the range of 3 - 5 tonnes per hectare, though up to 15 tonnes have been obtained
The bulbils of selected cultivars tend to be angular with a flattened shape and a skin-colour which evokes the name turkey liver yam. They may attain as much as 2 kg in weight but an average weight is about 0.5 kg. Races with increased bulbil production tend to show a reduction of the tuber, and in those with the highest bulbil return the tuber is but a woody rootstock. Bulbils are ready for harvesting when they fall off the plant at a slight touch
When produced, yields of 2 - 8 tonnes per hectare of the roots have been obtained
There are some named varieties
Aerial yam is a species of many races. The wild ones, which are toxic raw, have globose, dark brown to liver-coloured, non-angular bulbils which serve as a famine-food, as do the tubers. Wild strains are often planted intermixed with or on the perimeter of plantings of improved races as a protection against thieving. Cattle eating them accidentally may be fatally poisoned showing frothing at the mouth and bloating
The species is in the process of ennoblement and selected cultivars show in varying degree bitterness and poisonousness. Of some races even after prolonged preparation the bulbils remain bitter. Superior races are said to be very palatable and sweet, and to be entirely free from toxic substances so that consumption, even raw, is safe. The skin is grey, lighter coloured than the wild forms, and the flesh is pale yellow to near white.
A dioecious species, both male and female plants need to be grown if seed is required.

Propogation:

Seed - rarely produced, they are not normally used to propagate this species.
Cuttings of tubers. Small tubers can be cut into 2 - 4 sections, larger ones into 6 - 8 sections. Each section should have 2 - 3 dormant buds. The cut tuber is often left in the sun for several hours to promote wound healing and reduce the risk of fungal infection
Aerial tubers can also be used, they usually produce vigorous plants. The aerial bulbs are often divided into 2 or more equal sized pieces. Plants often need to be grown for two seasons in order to produce full-size aerial bulbs

Harvesting:

 Bulbils are ready for harvesting when they fall off the plant at a slight touch

STANDARDIZATION:

-Acharya Charaka in the context of Unmada (psychological disorder) Chikitsa, mentions Shukari as one of the ingredients of Mahapaishacha Ghrita and Chakrapani commenting on this says Shukari is Varahikanda. Acharya Sushruta has included Varahakanda in kanda varga and explains the qualities of Varahakanda. Dalhana commenting on this says Varahakanda is famous by the name Bakaluka. It is also called as Vaarahi and Gristika. Acharya Sushruta in Nivratasantapiya rasayana adhyaya, includes Varahi among the ashtadasha somasamaveerya aushadha and described it as a tuber having the capacity to regenerate and looks like a black snake. Acharya Vagbhata has mentioned Pindaaluka in Annaswarupavijnaniya adhyaya where Arunadatta in his commentary mentions Pindaalu as Varahikanda. Vaktraalu, Shabarakanda, Mulakamulabha, Twakchadha are the synonyms. 

Phytochemistry:

- Tubers reported to contain a poisonous glucoside.
- Tuber extract is rich in flavonoid, phenolics, reducing sugars, starch, diosgenin, ascorbic acid, and citric acid. 
- Study yielded14 compounds: : stigmasterol, mono-arachidin, 1,7-bis-(4-hydroxyphenyl)-1E,4E,6E-heptatrien-3-one, behenic acid, demethyl batatasin IV, 2,3-di-hydroxy-4,5-dimethoxybibenzyl, diosbulbin B, diosbulbin D, docosyl ferulate, 7-bis-(4-hydroxyphenyl) -4E, 6E-heptadien-3-one, 5,3,4-trihydroxy-3,7-dimethoxyflavone, tristin, protocatechuic acid, adenosine.
- Study yielded three norclerodane diterpenoids: diosbulbins K-M, and one enoglycoside, diosbulbinoside G, with four norclerodane diterpenoids, disobulbins B, E, F and G from the rhizomes

PHARMACOLOGY:

Parts used for medicinal purpose

Root tuber, ,

Dosage:

Churna (Powder) 3- 6 gm

Substitute:

Vrinda madhava mentions Charmakaraluka as substitute for Varahikanda

Controversy:

The controversy of Varahi might have started with the word Aaluka. The word Aaluka has been mentioned in Charaka Samhita as well as Sushruta Samhita. Acharya Charaka has told Aluka as ahitatama among the kanda and Acharya Sushruta has mentioned aluka in kanda varga and has given 6 varieties of Aluka. Both the commentators of Charaka and Sushruta Samhitas have given limited information regarding the morphological descriptions about these varieties. Acharya P.V. Sharma has correlated the varieties mentioned in Sushruta and Rajanighantu with different species of Dioscorea

Commercial value:

Diosgenin obtained from Dioscorea species is one of the major sources for the commercial production of corticosteroids and steroidal contraceptives

Morphology:

Dioscorea bulbifera, is an invasive plant not native to Florida but whose present-day distribution includes most of the state. It is a vigorously twining, long-stemmed herbaceous vine which may arise from an underground tuber, although often tubers are inconspicuous or absent. The stems are round to slightly angled in cross section and they twine coutner-clockwise. Conspicuous aerial tubers (called bulbils) are pale, round to globose in shape, up to 13 cm wide and are formed in leaf axils. It is these bulbils that give D. bulbifera the common name "air potato."

The leaves are attractive, alternate, broadly heart-shaped, up to 20 cm long and attached by long petioles. They are divided longitudinally into lobes by prominent arching veins all radiating out from a single point of origin where the petiole attaches to the leaf. Flowers rarely occur in D. bulbifera; where occurring, they are small, pale green and fragrant, arising from leaf axils. The fruit is a capsule and the seeds partially winged (Langland and Burks 1998, Langeland 2001).

Histology:

Rhizome shows a cork composed of 10 to 15 layers of thick-walled, tangentially elongated rectangular cells; outer few cells filled with reddish-brown contents; cortex consists of oval to elliptical, thin-walled parenchymatous cells; ground tissue, forming major portion of drug composed of oval to polygonal cells having a few scattered closed vascular bundles; starch grains found both in cortex and ground tissues, but abundant in ground tissue, rounded to oval, three sided with rounded angles or rod-shaped, simple, solitary or in groups, 11 to 28 n in diameter; hilum present at the narrower extremity.

Geographical distribution:

The broad native distribution of Dioscorea bulbifera includes much of Asia and Africa and the plant has been widely introduced to new tropical and subtropical areas including the Americas (Coursey 1967, Schultz 1993). In the U.S., D. bulbifera now occurs in Florida, Mississippi, Louisiana, Texas and Hawaii. D. bulbifera also occurs in Puerto Rico. In Florida, air potato now occurs throughout almost the entire peninsula.

ECOLOGICAL ASPECT:

No information is available at this time

Plant conservation:

This taxon has not yet been assessed.

General Use:

- In the wild, tubers, when fresh, are bitter.
- Cultivated tubers are less or non-bitter.
- Tubers considered tonic, expectorant, aphrodisiac and anthelmintic.

Therapeutic Uses:

Varahi choorna mixed with taila is applied externally in naadi vrana (S.Chi) 

Systemic Use:

-The dried and powdered tubers of Varahikanda also possess medicinal applications as they can be used to heal ulcers, piles and dysentery. The bulbils of Varahikanda are used externally to promote healing of sores. 

Administration:

-powdered root tuber

Pharmacological:

Balya, Pittakara, Rasayana, Svarya, Vrsya, Varnya, Slesmaghna, Ayurvardhana, Agnivrddhikara , Krmi, Kandu, Kustha, Prameha

Clinical trials:

Langeland, K.A. 2003. Natural Area Weeds: Air Potato (Dioscorea bulbifera). IFAS Publication SS AGR 164. Florida Cooperative Extension Service, Agronomy Department, University of Florida.

Research:

 Air Potato (Dioscorea bulbifera) Management Plan – Recommendations from the Air Potato Task Force, Florida Exotic Pest Plant Council, April 2008 (updated February, 2014). Overholt, W. A., L. Markle, M. Meisenberg, L. Raz, G. Wheeler, R. Pemberton, J. Taylor, M. King, D. Schmitz, G. R. Parks, M. Rayamajhi, E. Rohrig, E. Lake, M. Smith, K. Hibbard, T. D. Center, V. Manrique, R. Diaz and F. A. Dray. 2014. www.fleppc.org/publications.

Precautions:

Toxicity studies:

Use in other system of medicine:

Edibility / Culinary
- Tubers are reported edible, with a flavor similar to potato.
- Some report the tubers are poisonous when raw. 
Folkloric
- Tubers taken internally as remedy for dysentery and syphilis.
- Tubers used as resolvent for boils and as diuretic.
- Powdered tubers used as application for sores, piles and to stop diarrhea.
- In India, a folk remedy used to cure wounds, leucoderma and boils. Also, used as tonic, expectorant in asthma, as aphrodisiac and anthelmintic.
- In Chinese medicine, used to treat diseases of the lungs, kidney, spleen and many types of diarrhea.

CONCLUSION:

Varahikanda is a promising plant which has a wide range of chemical constituents. 

KEY WORDS: barahi Dioscorea bulbifera Linn. varahi kanda

• » Classification and names of barahi
• » Synonyms and definitions of barahi
• » Drug Properties of barahi
• » Chemical Constituents of barahi
• » Standardization of barahi
• » Parts used and Dosage of barahi
• » Morphology and Histology of barahi
• » Distribution and Conservation of barahi
• » Cultivation of barahi
• » barahi in the market
• » Medicinal Uses of barahi
• » Researches and clinical trails of barahi
• » barahi in other sytems of medicine
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