Abstract: The present disclosure is concerned with the production of high molecular weight hyaluronic acid suitable for medicinal administration to mammals without provoking an immune response from microbiological fermentation. The cultures may be prepared from specially developed strains of hyaluronic acid generating bacteria obtained by passaging in serologically negative host animal blood. The cultures are kept in log phase growth for an extended period by appropriate temperature, pH and glucose content adjustments. If the cultured strain is not hyaluronidase negative the hyaluronidase activity is inhibited. The hyaluronic acid is precipitated from the culture by the sequential addition of an anionic surfactant and then a cationic surfactant and extended from the precipitate with a high molarity aqueous calcium ion solution. The isolated aqueous hyaluronic acid solution may then be purified by passage through a nitrocellulose filter.

Abstract: Hyaluronic acid having controlled molecular weight and substantially free of protein and nucleic acids can be prepared from a hyaluronidase-negative or hyaluronidase inhibited microbiological source. Product may be used as replacement fluid in mammals.