Submerged Cultivation of Ganoderma lucidum Biomass in Stirred Tank Reactor

Abstract

European isolated strain Ganoderma lucidum, its biomass formation, intracellular and extracellular polysaccharide production in batch and repeated fedbatch cultivation, were studied. The best fed batch results were obtained in the first feeding at 141 h at productivity of biomass Px = 0.016 g g–1 h–1, intracellular Pi = 0.010 g g–1 h–1, extracellular polysaccharides Pe = 0.007 g g–1 h –1, and percent value of polysaccharides per cell dry weight Pi/x = 5.0 % and Pe/x = 3.0 %. Although four feedings increased the amount of fungal biomass by 42.66 %, productivities of fungal polysaccharides Pi = 0.010 g g–1 L–1 and Pe = 0.011 g g–1 L–1 showed that at the fourth feeding, the biomass was already exhausted and polysaccharide production was reduced. Therefore, 210 h batch cultivation with Px = 0.095 g g–1 L–1, Pi = 0.078 g g–1 L–1 at Pi/x = 33 % and extracellular polysaccharides Pe = 0.095 g g–1 L–1 at Pe/x = 6.8 %, was found to be the best mode for G. lucidum fungal biomass and polysaccharides production. Non-Newtonian cultivation broth rheology was found to be influenced entirely by the concentration and morphology of the biomass.

Keywords

• Ganoderma lucidum
• batch fermentation
• repeated fed batch
• stirred tank reactor
• fungal polysaccharides
• hydrodynamic behaviour