''Dioscorea composita'', or barbasco, is a species of yam in the genus '' Dioscorea'', native to

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

. It is notable for its role in the production of diosgenin, which is a precursor for the synthesis of

hormone A hormone (from the Greek participle , "setting in motion") is a class of signaling molecules in multicellular organisms that are sent to distant organs by complex biological processes to regulate physiology and behavior. Hormones are required ...

s such as

progesterone Progesterone (P4) is an endogenous steroid and progestogen sex hormone involved in the menstrual cycle, pregnancy, and embryogenesis of humans and other species. It belongs to a group of steroid hormones called the progestogens and is the m ...

Russell Marker Russell Earl Marker (March 12, 1902 – March 3, 1995) was an American chemist who invented the octane rating system when he was working at the Ethyl Corporation. Later in his career, he went on to found a steroid industry in Mexico when he s ...

developed the extraction and manufacture of hormones from ''D. mexicana'' at Syntex, starting the trade of ''D. composita'' in Mexico. Marker also discovered that the ''composita'' variety had a much higher content of diosgenin than the ''mexicana'' variety, and therefore it came to replace the latter in the production of synthetic hormones.

Chemical constituents

Steroidal sapogenin, diosgenin.

Medicinal use

It is a source of diosgenin, which is used to prepare synthetic

hormones A hormone (from the Ancient Greek, Greek participle , "setting in motion") is a class of cell signaling, signaling molecules in multicellular organisms that are sent to distant organs by complex biological processes to regulate physiology and beh ...

such as

and

cortisone Cortisone is a pregnene (21-carbon) steroid hormone. It is a naturally-occurring corticosteroid metabolite that is also used as a pharmaceutical prodrug; it is not synthesized in the adrenal glands. Cortisol is converted by the action of the enz ...

. Diosgenin extracted from ''Dioscorea composita'' was instrumental in the development of the

combined oral contraceptive pill The combined oral contraceptive pill (COCP), often referred to as the birth control pill or colloquially as "the pill", is a type of birth control that is designed to be taken orally by women. The pill contains two important hormones: proges ...

in the 1960s – and also for the development of cortisone treatments of

arthritis Arthritis is a term often used to mean any disorder that affects joints. Symptoms generally include joint pain and stiffness. Other symptoms may include redness, warmth, swelling, and decreased range of motion of the affected joints. In som ...

. Studies on Diosgenin say that it has effect on diabetic neuropathy. Before becoming used industrially the tuber was used by

Chinantec The Chinantec or Chinantecan languages constitute a branch of the Oto-Manguean family. Though traditionally considered a single language, ''Ethnologue'' lists 14 partially mutually unintelligible varieties of Chinantec.Palancar, Enrique L. (2014 ...

healers in northern

Oaxaca Oaxaca ( , also , , from nci, Huāxyacac ), officially the Free and Sovereign State of Oaxaca ( es, Estado Libre y Soberano de Oaxaca), is one of the 32 states that compose the political divisions of Mexico, Federative Entities of Mexico. It is ...

as an

abortifacient An abortifacient ("that which will cause a miscarriage" from Latin: ''abortus'' "miscarriage" and '' faciens'' "making") is a substance that induces abortion. This is a nonspecific term which may refer to any number of substances or medications, ...

and in cures for aching joints. It was also used by chinantecs as a poison for fishing in the

Papaloapan river The Papaloapan River () is one of the main rivers of the Political divisions of Mexico, Mexican state of Veracruz (state), Veracruz. Its name comes from the Nahuatl ''papaloapan'' meaning "river of the Butterfly, butterflies". In 1517, Juan de Gri ...

, and is also mentioned in use for this purpose in the

Popol Vuh ''Popol Vuh'' (also ''Popol Wuj'' or ''Popul Vuh'' or ''Pop Vuj'') is a text recounting the mythology and history of the Kʼicheʼ people, one of the Maya peoples, who inhabit Guatemala and the Mexican states of Chiapas, Campeche, Yucatan and ...

, the sacred book of the K'iche maya.

References

{{DEFAULTSORT:Dioscorea composita composita Yams (vegetable)