Dioscorea composita

Marker s synthesis was initially based on sarsasapogenin as starting material from root extracts of the Mexican sarsaparilla plant (Smilax aristolochiaefolia), and later on diosgenin. Diosgenin is found as the 3-glycoside (dioscin) in numerous Liliaceae and Dioscoreaceae species, and may be extracted with ethanol from the air-dried rhizomes of Dioscorea tokoro, Dioscorea macrostachya, Dioscorea mexicana, Dioscorea floribunda and Dioscorea composita (Barbasco). The extract is evaporated and heated with dilute hydrochloric or sulfuric acid to cleave the glycosidic bond. Subsequently, diosgenin is filtered off and used as such for the synthesis of steroid hormones. 

Q Healers of the native Chinantec people in northern Oaxaca, Mexico, already used the tuber of Dioscorea composita as an abortifacient, long before it gained any industrial significance. [27]... 

R. E. Marker, E. L. Wittle, E. J. Lawson, /. Am. Ghem. Soc. 60 (1938) 2931 http //en.wikipedia.org/wiki/Mexican barbasco trade http //en.wikipedia.org/ wiki/Dioscorea composita. 

Alkaloids are known in a few members of the family. Tests on 45 samples which included 37 species resulted in three positives in plants known to be alkaloidal (Dioscorea dumetorum, D. hispida, D. alaia) and in two of 13 other unidentified Dioscorea species. The remainder were negative Dioscorea abyssinica, D. alata, D. batatas, D. bucha-nanii, D. bulbifera, D. composita, D. cotinifolia, D. doryophora, D. dregeana, D. esculenla, D. hemicrypta, D. hirtiflora, D. mexicana, D. pentaphylla, D. quartiniana, D. retusa, D. sylvatica, D. trifida, Tamus edulis. 

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