AN OVERVIEW OF MIRACULOUS VEGETABLE DRUG - DIOSCOREA (YAM)

 

ABOUT AUTHORS:
Prashanta kr. Deb1, Tejendra Bhakta2*,
1Dept. of Pharmacy, Tripura University; Suryamaninagar –799 022, Agartala, Tripura (w).
2Regional Institute of Pharmaceutical Science & Technology, Abhoynagar – 799005, Agartala, Tripura (w).

shaandeb2010@gmail.com

INTRODUCTION
Dioscorea is a slender twining annual herbs distributed throughout the tropical and subtropical region of the world. Dioscorea is a fascinating plant with many uses in the history of the development of modern pharmacy. The number of species is quite overwhelming (over 600) and the Ethno-botanical uses are most interesting. Dioscorea is a genus of over 600 species of flowering plants in the family Dioscoreaceae. They are tuberous herbaceous perennial climber, growing to 2–12 m or more tall. The leaves are spirally arranged, mostly broad heart-shaped. The flowers are individually inconspicuous, greenish-yellow, with six petals; they are mostly dioecious, with separate male and female plants, though a few species are monoecious, with male and female flowers on the same plant. The fruit is a capsule in most species, a soft berry in a few species. Several species, known as yams, are important agricultural crops in tropical regions, grown for their large tubers. Some species produces large cylindrical tubers penetrating deep into the ground, while other varieties produce small or large tubers close to the soil surface. Sometimes 1-2 tubers are produce at the base of the plant while in the other cases cluster of tubers are observed. Many of these are toxic when fresh, but can be detoxified and eaten, and are particularly important in parts of Africa, and Asia.

REFERENCE ID: PHARMATUTOR-ART-1657

GEOGRAPHICAL DISTRIBUTION
Dioscorea is grown up to the altitude of 8000-15000 ft. above the sea level and normally does not grow in warm places. Yams are cultivated as garden crops by using both tuber tops and aerial tubers (bulbils), but the tuber crops are better for the rapid growing than the bulbils. A number of cultivated plants as well as wild varieties of yams are available throughout the state of Tripura. A different wild variety of yams grows in the forest of Tripura, which is yet to identify and evaluate for their food values. Tribal’s collect these yams from the dense forest during food scarcity.

Dioscorea alata is the most important species among the cultivated yams. It is grown as garden crops in every parts of Tripura. Yam grows abundantly in the several tracks and forest areas of Tripura. Dioscorea fasciculate is specially concentrated in the hilly forest region. The forest regions of Tripura like Kamalpur, Kailasahar, Sabroom, Belonia, Amarpur, Jampui, Longtarai etc. are the main places where the Tribals cultivate the yam and it also grows naturally.

In view of the pharmaceutical significance of drug, it is tried and successfully grown in various parts of India. Commercially, it is grown in Sikkim, Assam, Manipur, Arunachal Pradesh,Tamil Nadu, west Bengal, Maharashtra, Karnataka, and Jammu and Kashmir. D. deltoidea is found growing in north-western Himalayas from Kashmir and Punjab to Nepal and china upto an altitude of 1000 to 3000 m. It is cultivated in Jammu and Kashmir and in part of Himachal Pradesh. D. deltoidea is also found in U.S.A. and Mexico. 

HISTORY OF DIOSCOREA
"At the battle of Trenton in December, 1776, General Washington  captured   a   large   number of Hessian prisoners. Among them was a botanic physician,   Dr. Bone, who subsequently settled   in   New   Jersey,   a   few   miles   above   the   city   of Newark.   To him  belongs  the  credit  of  first  using  the  Dioscorea  villosa  as  a  medicine. He  appears  to  have  used  it  for  a  long  time  as  a  secret  remedy for  bilious  colic, and from   his   success   in   the administration of the medicine  in  this  disease, he named  it  colic  root. He  gave  to  the  patient  half  a  tea-cup  full  of  the  decoction,  every  half-hour;  the  second dose  rarely  failed  of  curing  this  truly  formidable  disease."

The above from the transactions of the Eclectic Medical Society of New York State, 1870, by Dr. D. E. Smith, of Brooklyn, is part of the   most   complete   paper   on   Dioscorea   to   that date. Just where Dr.Smith obtained his reference to Dr. Bone   we   have   been unable to find. The qualities of this drug were first authoritatively recorded in a book devoted to Materia medica, by Horton Howard. In the 18th and 19th centuries, herbalists used wild yam (Dioscorea villosa) to treat menstrual cramps and problems related to childbirth, as well as for stomach upset and coughs. In the 1950s, scientists discovered that the roots of wild yam (not to be confused with the sweet potato yam) contain diosgenin, a phytoestrogen (derived from plants) that can be chemically converted into a hormone called progesterone. Diosgenin was used to make the first birth control pills in the 1960s.Although herbalists continue to use wild yam to treat menstrual cramps, nausea, and morning sickness associated with pregnancy, inflammation, osteoporosis, menopausal symptoms, and other health conditions, there is no evidence that it works. Indeed, several studies have found that it has no effect at all. That is because the body cannot change diosgenin into progesterone; it has to be done in a lab. Wild yam, by itself, does not contain progesterone.

SELECTIVE SPECIES AVAILABLE IN TRIPURA
1. Dioscorea alata. (Eng: greater yam, Beng; Chupri alu, Kokborok; Thaduk).
2. Dioscorea bulbifera. (Eng; Potato yam, Beng; Banalu, Kokborok; Thwngwi).
3. Dioscorea puber. (Beng; Kukuralu, Hindi; Kasa alu, kokborok; Thacher).  
4. Dioscorea hamiltonii  ( Kokborok; Thakun)
5. Dioscorea esculenta. ( Eng; Lesser yam, Beng; Susnialu, kokborok; Thaktwi waksa)
6. Dioscorea pentaphyla ( Beng; Jhunjuna lata, Hindi; Kantaalu, kokborok; Kwiccha)
7. Dioscorea fluribenda (Beng:Gada alu).
8. Dioscorea glabra (Rheumatoid yam).

NUTRITIONAL VALUES
Most of the species of Dioscorea are used as vegetables in the same manure as the potato. The tubers of Dioscorea constitute a chief source of Carbohydrates mainly starch (75%). Tubers are used as famine food by the Tribals of Tripura. Some species like D. esculenta are sweet in taste. Tribals consume this Yam simply by boiling. Some species are poisonous. Tribals peeled and boiled properly to eliminate the alkaloid or other poisonous principles during cocking. Tribals of Tripura make different delicious dishes with these yams. Analysis of the edible tubers of Dioscorea showed the following values: Moisture (66-82%), Protein (1-2%), Fat (0.1-0.3%), Carbohydrate (18-25%), Minerals (0.5-1%), Fibers (o.1-1.5), Energy (65-124 Kcal/100gm), Calcium (16-52 mg/100 gm), Phosphorus (24-74 mg/100 gm), Iron (0.5-1 mg/100 gm), Niacin (1-1.5 mg/100 gm), VitaminC (1 mg/100 gm), Thiamin (0.1-o.2 mg/100 gm), Riboflavin (0.5mg/100 gm), Carotene (565µg/100 gm) Etc.

NOW YOU CAN ALSO PUBLISH YOUR ARTICLE ONLINE.

SUBMIT YOUR ARTICLE/PROJECT AT articles@pharmatutor.org

Subscribe to Pharmatutor Alerts by Email

FIND OUT MORE ARTICLES AT OUR DATABASE


Pages

FIND MORE ARTICLES