Physiological and Biochemical Properties of Agaricus bisporus in Shaking Flask Culture

  Objective  Mycelial growth of Agaricus bisporus W192 in a shaking flask was monitored to determine viability of the culture method for scale-up application.

  Method  Physiological and biochemical properties of A. bisporus mycelia biomass in the liquid culture including the number and diameter of mycelium pellets, pH of fermentation broth, content of reducing sugar and amino nitrogen as well as the activity of extracellular carboxymethyl cellulase, amylase, acid protease, and laccase were monitored for the analysis.

  Result  On the 8th day of culture, the fungal biomass reached a maximum at 9.7 mg·ml⁻¹, the greatest number of mycelium pellets of 880 CFU·mL⁻¹, the largest average diameter of mycelium at 0.809 mm, the peak reducing sugar and amino nitrogen contents at 5.228 and 0.079 mg·ml⁻¹, respectively, and the highest activities of carboxymethyl cellulase, amylase, and laccase of 0.69 , 2.11 , and 15.02 U, respectively. The acid protease activity of 2.93U maxed on the 10th day. By transferring the mycelia in a simulated liquid fermentation tank after 8d of culture, 115 CFU·mL⁻¹ of mycelium pellets and 7.56mg·mL⁻¹ in biomass were obtained.

  Conclusion  The mycelial growth of A. bisporus in the liquid shaking flask culture correlated with some of selected physiological and biochemical indices. The established method was deemed applicable for tank fermentation in propagating A. bisporus for large scale production of the mushroom.