| 摘要 |
FIELD: chemistry.SUBSTANCE: method of producing substantially pure heparosan from E.coli K5, comprises culturing E.coli K5 in a medium with glucose as the primary carbon source, binding heparosan to a solid-phase carrier with subsequent elution and precipitating heparosan from the eluate. Said culturing includes batch culturing phase and a batch fed culturing phase. The medium used at the batch culturing step contains (per litre) about 20 g glucose, 10-300 mg thiamine, about 13.5 g KHPO, about 4.0 g (NH)HPO, about 1.4 g MgSO·7HO, about 1.7 g citric acid, and about 10.0 ml solution of trace elements, the solution of trace elements substantially consists of (per 1 l 5M HCl) 10.0 g FeSO·7HO, 2.0 g CaCl, 2.2 g ZnSO·7HO, 0.5 g MnSO·4HO, 1.0 g CuSO·5HO, 0.1 g (NH)MoO·4HO and 0.02 g NaBO·10HO. The feed medium used at the batch fed culturing step contains (per litre): 250-1000 g glucose, 20 g MgSO, 0.15-0.5 g thiamine and, optionally, 47 g KHPO. Oxygen is supplied by bubbling air with or without additional supply of oxygen.EFFECT: method enables to obtain at least 90% pure heparosan.14 cl, 12 dwg, 1 tbl, 3 ex |
