Strain of Ganoderma japonicum with higher mycelial growth rate and higher levels of polysaccharide production was selected from seven tested strains of Ganoderma.The effects of nitrogen source,carbon source and metal ions on the polysaccharide production of selected Ganoderma japonicum were studied.The results showed that the optimum nitrogen source and carbon source were 2% and 0.2%,respectively.And the existence of 0.2% Fe2+ could improve the polysaccharide yield significantly.The result of fermentor enlargement test indicated that extracellular crude polysaccharide content per 100 mL fermentation liquor and mycelium content yielded highest amount of 181.7 mg and 151.0 mg,respectively,with relatively mild change of pH value.It was concluded that fermentation in fermentor was more suitable for the secretion of Ganoderma polysaccharide.
