VERFAHREN ZUR HERSTELLUNG VON HYALURONSÄURE MIT HOHEM MOLEKULARGEWICHT

A process for purifying hyaluronic acid (HA) or its salt from a bacterial fermentation broth comprising: (a) diluting and clarifying the fermentation broth; (b) precipitating the HA present in the broth with an equal volume of solvent; (c) dissolving the precipitated HA or its salt in a solution; (d) adding silica gel to the HA solution or HA salt solution from step (c) and then removing the silica gel; (e) treating the HA solution or HA salt solution from step (d) with active carbon; and (f) diafiltrating the HA solution or HA salt solution from step (e) using about 5 volumes of solvent; wherein the process is conducted in the absence of any detergent or surfactant or formalin, and at neutral pH.