Control of Grifola frondosa Morphology by Agitation and Aeration for Improving Mycelia and Exo-Polymer Production.

Abstract

The present study describes the improved mycelia and exo-polymer production under control of Grifola frondosa morphology by changing the aeration rate and agitation intensity in a 25-L stirred fermentor. The aeration rate of 1.0vvm yielded a highest mycelia biomass of 24.754g/L with the lowest pellet percentage of 20.5%. The maximum exo-polymer (2.324g/L) was achieved at 0.75vvm with mycelia polysaccharide production (0.321g/g), whereas clumps and filaments dominated the ratios of 45.6 and 33.9%, respectively. The change of aeration rate and agitation intensity had slight influence on the monosaccharide compositions in exo-polymers and significantly affected glucose and mannose contents in the mycelia polysaccharides. These findings will provide a clue for exploring the relationship between fermentation parameters, morphologies, and polysaccharide synthesis pathway of G. frondosa.