Experimental Analysis of Extracellular Enzymes Activity of Grifola frondosa Supplemented with Rhizoma gastrodiae Alcohol Extract by Submerged Fermentation

Abstract

Grifola frondosa was cultured with Rhizoma gastrodiae alcohol extract by submerged fermentation to study the growth of mycelia and analyze the changes in the activity of extracellular enzymes related to substrate degradation. It turned out that Rhizoma gastrodiae alcohol extract at 7 g/L significantly increased the biomass of Grifola frondosa. Interestingly, levels of reducing sugars in the medium initially increased and then decreased at the last stage. Moreover, dynamic detection of mycelial biomass and extracellular enzymes involved in degradation of nutritional ingredients of the medium indicated that Rhizoma gastrodiae alcohol extract at 7 g/L stimulated the growth of mycelia and augmented the activity of extracellular enzymes to a variable extent and thus increased degradation ability of Grifola frondosa. This paper firstly revealed the mechanism for the stimulation of mycelial biomass growth in Grifola frondosa by Rhizoma gastrodiae alcohol extract in liquid culture through activity of extracellular enzymes related to the degradation of the substrates.