Cordyceps sinensis (sexual stage/teleomorph)
Hirsutella sinensis (asexual stage/anamorph)
C. sinensis known as 'yarsa gumba' in Tibet and keera jhar in India, but it is known in the West primarily from its use in Chinese medicine. Its name in Chinese (dong cong xia cao) translates literally as "worm in winter, plant in summer", commonly abbreviated as dong cong cao. The Chinese believe that dong cong cao is a caterpillar in winter, but that in the summer it grows into a plant. This general ignorance regarding the nature of Cordyceps means great profits for the unscrupulous; I have seen dried caterpillars on sale in Chinese medicine halls with no visible cordyceps attached.
Mycology & Taxonomy
The fungi of genus Cordyceps are parasites of insects. C. sinensis is a parasite of the caterpillar of moths of the genus Hepialus. The caterpillar lives in underground tunnels, emerging at night to feed on roots. The fungus grows and invades the body of the caterpillar, eventually killing and mummifying it. The black fruiting body (or mushroom) emerges from the ground in the spring time, always arising from the head of the dead caterpillar.
The asexual stage (anamorph) is Hirsutella sinensis (Chen 2001). Identification of the asexual stage was difficult until the advent of molecular methods; but we now know that Cordyceps sinensis and Hirsutella sinensis are simply different stages in the life cycle of the same organism. Previous identifications with Paecilomyces sinensis, Staphybotrys sp. and Tolypocladium sp. are proven to be incorrect.
The sexual stage has never been successfully grown, and commercial preparations therefore use the asexual stage, because that can be produced in quantity.
Ecology & economy
Cordyceps sinensis is native to the Himalayas and most of the world supply of cordyceps comes from Tibet, with smaller harvests from Nepal and India. The fungus exists in the wild in very difficult terrain, which explains the high price it commands. It normally exists only at altitudes above 4000m and tends to grow where yaks graze.
C. sinensis is traded commerically, but most of the trade is not reported or regulated in any fashion. It has not so far been possible to culture C. sinensis for its fruiting body. The quality of the ingredients is extremely variable and any number of alternative products are sold under the banner of 'Cordyceps sinensis,' e.g. C. militaris or even dried caterpillars with no active ingredient. The current price for a kilogram of C. sinensis is US$700 to US$800 per kilogram.
Medicinal uses
The part of C. sinensis traditionally used is the fruiting body (or mushroom). The medicinal properties of the fungus have been known to the Tibetans for about 1500 years. Sheperds noticed that their flock became particularly entergetic after consuming the fungus and it is still used locally to increase the energy level of pack animals at high altitude, although the high price of the fungus now makes this economically unfeasible for the local people. The fungus has been known to Chinese medicine since the Ming Dynasty, and to it is attributed a myriad of beneficial properties, some more believable than others: among its published uses are those as an aphrodisiac, a lipid lowering agent, against cancer, against asthma and against hepatitis B. This list is
by no means exhaustive.
References
- Chen YQ, Wang N, Qu L, Li T, Zhang W (2001) 'Determination of the anamorph of Cordyceps sinensis inferred from the analysis of the ribosomal DNA internal transcribed spacers and 5.8S rDNA' Biochem Syst Ecol 29(6):597–607
- Sharma S (2004) 'Trade of Cordyceps sinensis from high altitudes of the Indian Himalaya: Conservation and biotechnological priorities' Current Science 86(12):1614–1619
This document created 30 Aug 2005