Process for producing high molecular weight hyaluronic acid

摘要

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.