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''Cordyceps'' is a genus of ascomycete fungi (sac fungi) that includes about 400 species. All ''Cordyceps'' species are endoparasitoids, parasitic mainly on insects and other arthropods (they are thus entomopathogenic fungi); a few are parasitic on other fungi. Until recently, the best known species of the genus was ''Cordyceps sinensis'', first recorded as ''yartsa gunbu'' in Nyamnyi Dorje's 15th century Tibetan text ''An ocean of Aphrodisiacal Qualities''.〔Winkler, D. 2008a. Yartsa Gunbu (Cordyceps sinensis) and the Fungal Commodification of the Rural Economy in Tibet AR. Economic Botany 63.2: 291–306〕 and known as ''yarsha gumba'' in Nepali and ""summer-grass, winter-worm" in English. In 2007, nuclear DNA sampling revealed this species to be unrelated to most of the rest of the genus' members; as a result it was renamed ''Ophiocordyceps sinensis'' and placed in a new family, the Ophiocordycipitaceae. The generic name ''Cordyceps'' is derived from the Greek word ''kordyle'', meaning "club", and the Latin stem ''-ceps'', meaning "head". Several species of ''Cordyceps'' are considered to be medicinal mushrooms in classical Asian pharmacologies, such as that of traditional Chinese and Tibetan medicines. When a ''Cordyceps'' fungus attacks a host, the mycelium invades and eventually replaces the host tissue, while the elongated fruit body (ascocarp) may be cylindrical, branched, or of complex shape. The ascocarp bears many small, flask-shaped perithecia containing asci. These, in turn, contain thread-like ascospores, which usually break into fragments and are presumably infective. Some current and former ''Cordyceps'' species are able to affect the behaviour of their insect host: ''Ophiocordyceps unilateralis'' (formerly ''Cordyceps unilateralis'') causes ants to climb a plant and attach there before they die. This ensures the parasite's environment is at an optimal temperature and humidity, and that maximal distribution of the spores from the fruit body that sprouts out of the dead insect is achieved. Marks have been found on fossilised leaves that suggest this ability to modify the host's behaviour evolved more than 48 million years ago. The genus has a worldwide distribution and most of the approximately 400 species have been described from Asia (notably Nepal, China, Japan, Bhutan, Korea, Vietnam, and Thailand). ''Cordyceps'' species are particularly abundant and diverse in humid temperate and tropical forests. Some ''Cordyceps'' species are sources of biochemicals with interesting biological and pharmacological properties, like cordycepin; the anamorph of ''C. subsessilis'' (''Tolypocladium inflatum'') was the source of ciclosporin—an immunosuppressive drug helpful in human organ transplants, as it inhibits rejection. ==Potential pharmacology== ''Cordyceps'' have a long history of use in traditional medicine. One of the earliest clear records is a Tibetan medical text authored by Zurkhar Nyamnyi Dorje in the 15th century outlining the tonic propensities of Yartsa gunbu (''Cordyceps sinensis'' renamed now to ''Ophiocordyceps sinensis''), especially as an aphrodisiac.〔 Although there are often-repeated claims of thousands of years of use in traditional Chinese medicine, so far no clear textual source has surfaced. Although ''in vitro'' and animal models provide preliminary support for some of the traditional medicinal uses, there are no clinical studies demonstrating health benefits in humans or for "elderly populations, improved sexual drive and virility" and "improved renal function".〔(Cordyceps ) information from Drugs.com〕 Some polysaccharide components and cordycepin, which have some anticancer activity in preliminary ''in vitro'' and animal studies, have been isolated from ''C. militaris''. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「cordyceps」の詳細全文を読む スポンサード リンク
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