Optimization of Cordyceps sinensis fermentation Marsdenia tenacissima process and the differences of metabolites before and after fermentation

In this paper, we explored the interaction of factors which influenced the Cordyceps sinensis fermentation Marsdenia tenacissima (Roxb.) Wight et Arn, a Dai (a national minority of China) medicine, and the optimal fermentation conditions. The differences of C. sinensis metabolites in normal state (CN) and products of two-way liquid fermentation of C. sinensis and Marsdenia tenacissima (CM) and Marsdenia tenacissima (MT). The interactive effect of factors was analyzed and the best conditions are obtained through the box-behnken design (BBD) in response surface methodology (RSM). All metabolites were determined by ultra high performance liquid chromatography quadrupole time of flight mass spectrometer (UHPLC-Q-TOF-MS), analyzed and identified by metabonomics technology. Results showed that the optimum fermentation conditions were the concentration of raw medicinal materials is 160 g/L, the fermentation time is 6 days, the inoculation volume is 9.5%, the rotating speed is 170 rpm. 197 metabolites were identified in both positive ion and negative ion. 119 metabolites were significantly different between CN and CM. 43 metabolites were significantly different between CM and MT. Differential metabolic pathways were enriched. In conclusion, this paper optimizes the bidirectional fermentation process of M. tenacissima and C. sinensis through response surface methodology, and analyzes the changes of components from the level of metabonomics, so as to provide reference for exploring medicinal fungi fermentation of traditional Chinese medicine.