Comparative metabolic profiling of Ophiocordyceps sinensis and its cultured mycelia using GC-MS.

Ophiocordyceps sinensis, one of the well-known traditional Chinese medicine, has multiple health-promoting effects. It is used as herbal remedy and health food in Asian countries, together with its cultured mycelia used as a substitute of natural O. sinensis. In the present study, natural O. sinensis collected from three geographical regions and its cultured mycelia derived from three strains were analyzed by gas chromatography-mass spectrometry (GC-MS) combined with chemometrics. A total of 72 metabolites were identified from all samples with different metabolic profiles observed between natural O. sinensis and cultured mycelia. Among them, 50 metabolites showed significant differences between natural O. sinensis and cultured mycelia. Higher levels of trehalose, glycerol and citric acid in natural O. sinensis were found compared to those in cultured mycelia, while myo-inositol and some amino acids were more abundant in cultured mycelia. In addition, chemical compositions of natural O. sinensis varied depending on the geographical regions. Natural O. sinensis from three locations were clearly differentiated by the concentrations of meso-erythritol, D-mannitol, glucose and organic acids. The current study provides a comprehensive metabolic profiles of natural O. sinensis and its cultured mycelia, which is potentially important for understanding the metabolism of O. sinensis and facilitating the application of cultured mycelia as a supplement of natural O. sinensis.