| abstract |
Above all, a new microorganism, Streptococcus zooepidemicus HA-116 ATCC 39920, produces large quantities of high molecular weight hyalyronic acid. The invention describes a process for obtaining these microorganisms, as well as a process for producing sodium hyaluronate which consists in cultivating, with vigorous stirring, a microorganism of the genus Streptococcus under suitable conditions and in a nutritive medium containing a sugar component. as a carbon source. The sugar component has a substantially constant content of between 0.2 and 10 grams per liter. The medium has a substantially constant pH of between 6.0 and 7.5 and comprises a substantially constant content of magnesium ions greater than 0.05 grams per liter. The sodium hyaluronate excreted in the medium by the body is purified by methods of precipitating, redissolving and reprecipitating the hyaluronate. One thus obtains compositions based on sodium hyaluronate characterized by the absence of pyrogenicity and which does not irritate the skin. |