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生物工程学报 2000
Nutrition Condition of Hyaluronic Acid Fermentation with Streptococcus zooepidemicus
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Abstract:
Based on the analysis of metabolic pathway Streptococcous zooepidemicus for hyaluronic acid (HA) synthesis, nucleotide, especially uracil, was considered to be important to cell growth and metabolism. When 0.005 g.L-1 uracil added in the media in which yeast extract as complex nitrogen source, cell growth and HA production were increased by 32% and 34% respectively. From analysis of amino acid in fermentation process, it was show that arginine(Arg) was needed for cell metabolism, and concentration of free Arg maintained at 0 g.L-1 in fermentation process, which was proposed to limit cell growth and HA production. By shake-flask experiment HA concentration reached 0.510 g.L-1 when 0.06 g.L-1 Arg added, in the fermentation with 2.5 L fermentor, when uracil 0.005 g.L-1 and Arg 0.06 g.L-1 were added, the rate of cell growth increased, maximum of specific growth rate, concentration of HA and HA molecular weight reached 0.67 h-1, 5.2 g.L-1 and 2.15 x 10(6) Da from 0.54 h-1, 4.2 g.L-1, 2.0 x 10(6) Da, respectively.