Authentication and quality control of Cordyceps sinensis, a traditional Chinese medicine known as winter-worm summer-grass

Cordyceps, one of the most valued traditional Chinese medicines, consists of the dried fungus Cordyceps sinensis growing on the larva of caterpillar. It is also known as 'winter-worm and summer-grass' because of its appearance during different seasons. The parasitic complex of the fungus and the caterpillar is found in soil of a prairie at an elevation of 3,500 to 5,000 meters in northwestern part of China. According to Chinese medicinal theory, Cordyceps is used to replenish the kidney and soothe the lung, and indeed many clinical applications have been reported. The natural Cordyceps is rare and expensive on the local market, and therefore, several mycelial strains have been isolated from natural Cordyceps and manufactured in large quantities by fermentation technology, and they are commonly sold as health food products in Orient. The adulterants of Cordyceps are commonly found on the market, and therefore the authentication of these products has to be defined. Having the urgent need from current market, different chemical markers such as nucleoside, ergosterol, mannitol and polysaccharide are being used for quality control of Cordyceps. Unfortunately, these markers are far from optimization, and therefore extensive works are needed to define the pharmacological efficiency of these markers.