Artificial cordyceps mycelium by submerged fermentation of Hirsutella sinensis HS 1201 using rice bran hydrolysate as substrate

Abstract

AbstractArtificial cordyceps mycelium (CM) is a potential substitute for natural cordyceps. In this study, rice bran hydrolysate (RBH), from the residual of the food process, was applied as substrate for submerged fermentation. The active compounds’ constituents in CM were investigated in detail. Results indicated that RBH could not only be used as nutriments and facilitate the submerged fermentation but also showed the ability to promote the metabolism of active ingredients by Hirsutella sinensis HS 1201. Key parameters of the fermentation process were optimized. Under the optimized conditions (pH 6.5, silkworm chrysalis powder 4 g/L, and yeast extract 6 g/L), 15.1 ± 0.6 g/L of the CM was obtained, which was 77.6% higher than the control group that using the conventional synthesis medium. For the constitution of the bioactive compounds, the adenosine content in the CM reached 176 ± 11 mg/100 g, which was increased by 11.4% compared to the control. The concentration of ergosterol in the dry CM was 320 ± 20 mg/100 g, and the cordycepin concentration was 9.66 ± 0.55 mg/100 g. At the same time, lipid yield was 1.2 times higher than that obtained in the control group. The cordyceps polysaccharide content was also increased to 162.3 ± 8.6 mg/g using the RBH‐based medium.