| 摘要 |
PURPOSE:To obtain hyaluronic acid useful as a water-retaining material, etc., on an industrial scale at a low cost by culturing a hyaluronic acid-producing microbial strain belonging to the genus Streptococcus in a nutrient medium containing a specific amount of a sugar component as main carbon source under specific condition while stirring the medium by aeration. CONSTITUTION:A microbial strain belonging to the genus Streptococcus and capable of producing hyaluronic acid (e.g. Streptococcus zooepidemicus) is inoculated on a nutrient medium containing >=3% sugar component as a main carbon source and cultured at pH 7 and 33 deg.C for 4 days under stirring by aeration. The cultured liquid is subjected to centrifugal separation to remove microbial cells and other foreign materials. The supernatant is incorporated with 2 times volume of ethanol under stirring and the precipitated fibrous substance is separated by filtration, washed, redissolved in water and incorporated with cetylpyridinium chloride. The produced precipitate is separated by filtration and extracted with 0.5M NacCl. The extracted liquid is dialyzed, desalted and freeze-dried to obtain the hyaluronic acid in high efficiency. |
