Submerged fermentation of higher fungus Ganoderma lucidum for production of valuable bioactive metabolites-ganoderic acid and polysaccharide

The effects of nitrogen source and initial glucose concentration were studied in submerged fermentation of higher fungus Ganoderma lucidum for simultaneous production of bioactive ganoderic acid and polysaccharide. The cells could not grow well when either yeast extract or peptone was used as the sole nitrogen source. However, a combined. addition of 5 g/l of yeast extract and 5 g/l of peptone was optimal for the cell growth and metabolite production. Initial glucose concentration within 20-65 g/l also greatly affected the cell growth and product biosynthesis. The extracellular polysaccharide production was remarkably improved at a high initial glucose concentration. The highest levels of cell density (16.7 g DW/l), intracellular polysaccharide (1.19 g/l) and ganoderic acid (212.3 mg/l) were obtained at an initial glucose concentration of 50 g/l. (C) 2002 Elsevier Science B.V. All rights reserved.