Mycelial biomass and intracellular polysaccharides yield of edible mushroom Agaricus blazei produced in wheat extract medium

The aim of this work was to evaluate the potential of wheat extract as basal medium for the submerged fermentation of Agaricus blazei Murrill (ABM) and optimize the medium and fermentation conditions to obtain maximal mycelial biomass and intracellular polysaccharides (IPS) yield of this fungus. In the basal medium, the mycelial biomass and IPS yield of ABM was respectively 2.01 g/L and 93.42 mg/L. Supplementation of peptone and maltose to the basal medium caused a significant increase in either mycelial biomass or IPS yield as compared with control (P < 0.05). Through response surface methodology, the optimum wheat extract medium for the submerged fermentation of ABM was the following: 1000 mL wheat extract, 3.44 g peptone, 43.00 g maltose, 1.00 g KH2PO4 and 0.50 g MgSO4. Through orthogonal experiments, the optimum fermentation conditions were the following: inoculation volume of 10% (v/v), medium volume of 70 mL per flask and rotation speed of 170 rpm. By the optimization of medium and fermentation conditions, the mycelial biomass and IPS yield of ABM reached their maximum values of 16.02 g/L and 1041.32 mg/L, respectively.