Study on fermentation condition for production of huperzine A from endophytic fungus 2F09P03B of Huperzia serrata

Abstract

Objective To investigate the effects of fermentation conditions on the production of huperzine A from an endophytic fungus 2F09P03B of huperzia serrata. Methods Growth curve, huperzine A accumulation curve, and the pH value in culture fluid at different fermentation time of the 2F09P03B was analyzed to investigate its characteristics for culture. The effects of carbon and nitrogen sources on the accumulation of huperzine A was studied, and the the composition of carbon and nitrogen sources was optimized through orthogonal experiment based on the result of single-factor analysis. The effects of MgSO4, KH2PO4, NaCl, and CaSO4 on the accumulation of huperzine A was investigated by orthogonal experiment to determine the composition of inorganic salts. The fermentation conditions including cultural temperature, ratational speed of rocking bed, the quantity of inoculation, fermentation time was optimized by another orthogonal experiment. Results The optimum medium composition for strain 09P03B was as follows: potato extract 150 g/L, yeast extract 10 g/L, maltose 25 g/L, corn flour 30 g/L, wheat bran 30 g/L, KH2PO4 1.5 g/L, MgSO4 0.5 g/L, NaCl 0.3 g/L, CaSO4 0.3 g/L, with natural pH. The optimum fermentation conditions included quantity of inoculation 8%, fermentation time 10 d, cultural temperature 28 ℃, ratational speed of rocking bed 140 r/min. Under these conditions, the production of huperzine A from the strain 2F09P03B amounted to 8.17 μg/L, with a maximal value of 8.32 μg/L, which was about 0.07% of its dry weight. Conclusions The fermentation condition markedly affects the production of huperzine A from the strain 2F09P03B. Since the optimized fermentation condition significantly increases the production, it can be a new medicinal resources of huperzine A.