Wall ex Griseb.
Synonym: D. nepalensis Sweet ex Bernardi.
Family: Dioscoreaceae.
Habitat: The Himalaya from Kashmir to Arunachal Pradesh and in Assam at 450-3,100 m.
Ayurvedic: Vaaraahikanda (var.), Grishti.
Folk: Gun, Kris (Punjab).
Action: Tuber—antipthiriac. Leaf— febrifuge. The rhizomes are a rich source of diogenin and its glycoside. Steroidal saponins have also been isolated. Diogenin is used in the preparation of various steroidal drugs.
Synonym: D. hispada Dennst. D. hirsuta Dennst.
Family: Dioscoreaceae.
Habitat: Sikkim, the Himalayas, Khasi Hills.
Linn.
Synonym: D. atropurpurea Roxb. D. globosa Roxb. D. purpurea Roxb.
Family: Dioscoreaceae.
Habitat: Native to East Asia; cultivated in Assam, Vadodara, Tamil Nadu, Bengal and Madhya Pradesh.
English: Wild Yam, Greater Yam, Asiatic Yam.
Ayurvedic: Kaashthaaluka. Aaluka (var.). Aalukas (yams) of Ayurvedic texts, belong to Dioscorea spp.
Siddha/Tamil: Perumvalli kizhangu.
Folk: Kathaalu.
Action: Even the best among the cultivated yams causes irritation in the throat or a feeling of discomfort when eaten raw. Wild yams—cholagogue, antispasmodic, anti-inflammatory, antirheumatic, diuretic. Also used for painful periods, cramps and muscle tension.
Key application: Dioscorea villosa L., Wild Yam—as spasmolytic, anti-inflammatory. (The British Herbal Pharmacopoeia.)The edible tubers of Dioscorea alata are purple-coloured and contain an- thocyanins, cyanidin and peonidin- 3-gentiobioside acylated with sinapic acid. The tubers contain surcose, while leaves contain large quantities of D- fructose, D-glucose and the polyols, 2-deoxyribitol, 6-deoxysorbitol and glycerol.Mouldy yams are reported to contain a compound ipomeanol which is being tested against human lung cancer. (J. Am Med Assoc, 1994,15, 23.)Diosgenin obtained from Dioscorea species was used in the first commercial production of oral contraceptives, topical hormones, systemic corticos- teroids, androgens, estrogens, pro- gestogens and other sex hormones.The chemical transformation of di- osgenin to estrogen, progesterone or any other steroidal compound does not occur in human body. Topically applied Wild Yam does not appear to cause changes in serum FSH, estradi- ol or progesterone. (Natural Medicines Comprehensive Database, 2007.)Diosgenin, combined with the drug clofibrate, caused a greater decrease in LDL than either substance alone in rats. (Sharon M. Herr.)... dioscorea alata
Linn.
Synonym: D. sativa Thumb auct. non L.D. versicolor Buch.-Ham ex Wall.
Family: Dioscoreaceae.
Habitat: Throughout tropical India, at 1,500-2,100 m.
English: Patoto Yam, Bulb-bearing Yam, Air Potato, Dog Yam.
Ayurvedic: Vaaraahi, Vaaraahikan- da, Grshti, Banaaalu, Suraalu, Raktaalu. Substitute for Vriddhi.
Unani: Baraahikand.
Siddha/Tamil: Kodi-kilangu, Pannu-kilangu.
Action: Dried and pounded tubers are used as an application for swellings, boils and ulcers; roasted tubers are used in dysentery, piles, venereal sores. Leaf—febrifuge.
The raw tubers are bitter due to the presence of furanoid norditerpenes (they lose their bitterness on roasting and are then eaten). The wild tubers contain nearly 83% starch and possess hunger-suppressing property. They contain certain poisonous alkaloids.The rhizomes afforded D-sorbitol, furanoid norditerpenes—diosbulbins A-D, 2,4,6,7-tetrahydroxy-9,10-dihy- drophenanthrene and 2,4,5,6,-tetra- hydroxyphenanthrene, diosgenin, lucein, neoxanthine, violaxanthin, zeax- anthin, auroxanthin and cyrptoxan- thin.... dioscorea bulbifera