| 摘要 |
Disclosed is a preparation process for A-group Neisseria meningitidis bacterium capsule crude polysaccharide. The present invention comprises the following steps: (1) sterilizing cultivated Neisseria meningitidis by using formaldehyde, and centrifugating the sterilized culture solution and collecting a supernate; (2) adding CTAB to the supernate untill the final concentration of the CTAB is 1.0 g/L, then performing standing overnight after full stirring, and collecting polysaccharide by means of centrifugation; (3) stirring the precipitated polysaccharide for 3 hours by using a calcium chloride solution, and collecting the supernate by means of centrifugation; (4) adding ethanol to the supernate untill the final concentration by volume of the ethanol is up to 20%-25%, performing standing at the temperature of 2-8°C overnight, collecting the supernate by means of centrifugation, then adding ethanol to the supernate untill the final concentration by volume of the ethanol is up to 75%-80%, performing full shaking, performing standing for more than 18 hours, and collecting a precipitate by means of centrifugation; and (5) performing washing by using absolute ethanol and acetone for three times respectively, and then drying to obtain crude polysaccharide. The present invention has the advantages of high extraction efficiency and the like. |
