Optimization of fermentation conditions for crude polysaccharides by Morchella esculenta using soybean curd residue

Abstract

In this study, orthogonal experimental design and response surface methodology were employed to optimize the fermentation conditions for crude polysaccharides (MPS) production from the strain Morchella esculenta (M. esculenta) by soybean curd residue (SCR). The MPS yield varied depending on the nutrition contents added in SCR and fermentation time, fermentation temperature and inoculum size by M. esculenta during solid-state fermentation. The optimal fermentation conditions achieved for MPS production 95.82±1.37mg/g were glucose 4%, (NH4)2SO4 1.5%, water 75% and MgSO4·7H2O 0.2%, fermentation temperature 22.6°C, fermentation time 21 days and inoculum size 2.67%, respectively. Furthermore, purified polysaccharides (PMPS) exhibited a positive antioxidant activity. The results provide a reference for large-scale production of polysaccharides by M. esculenta using SCR in the medical and food industries.