Metabolomic profiling reveals enrichment of cordycepin in senescence process of Cordyceps militaris fruit bodies.

Cordyceps militaris is a species of Cordyceps that is classified in the Cordycipitaceae family and is well known in East Asia as a traditional medicinal mushroom. Its artificial fruit body has been widely cultivated for commercial use in cosmetics, functional food, and medicine. To explore the metabolites associated with fruit body development, we conducted gas chromatography mass spectrometry (GC-MS) analyses based on developmental stage, which was divided into the growth period (stage 1, stage 2, and stage 3) and aging period (stage 4). We detected 39 biochemical metabolites associated with nucleotide, carbohydrate, and amino acid metabolism. Cordycepin, one of the representative bioactive compounds in C. militaris, was significantly enriched in stage 4 of aging period and is associated with glucose accumulation. The accumulation of cordycepin in stage 4 of aging period also seems to be related to the glutamine and glutamic acid pathway. Our results also showed enrichment of other bioactive compounds such as mannitol and xylitol in stage 4 of aging period. Our metabolomic profiling based on the developmental stages of C. militaris is useful for exploring bioactive compounds (e.g., cordycepin, mannitol, GABA, and xylitol) that are enriched in stage 4 of aging period and understanding the biosynthetic mechanisms associated with cordycepin production. Through optimization of fruit body cultivation by selecting stage 4 of aging period as a harvesting time, our findings can be utilized in food and medical applications of C. militaris in future.