Pharmacologically active fraction of hyaluronic acid, its preparation and pharmaceutical composition

PROBLEM TO BE SOLVED: To obtain a hyaluronic acid fraction that is pure and noninflammatory and is useful for a wound healing promotor or the like by extracting a mixture of a hyaluronic acid from a starting material containing a hyaluronic acid, subjecting the mixture to molecular filtration and isolating a fraction with a specific molecular weight. SOLUTION: A mixture of a hyaluronic acid is extracted form an available starting material containing a hyaluronic acid, the mixture obtained undergoes molecular filtration, for example, using a membrane with a molecular exclusion limit of about 30,000, and a hyaluronic acid fraction with an average molecular weight of 30,000-730,000 is isolated, whereby the hyaluronic acid fraction, substantially free of a hyaluronic acid with a molecular weight of not more than 30,000, is obtained. It is preferable that the mixture of the hyaluronic acid obtained from a solvent extraction is exposed to an enzymatic digestion by the use of papain. COPYRIGHT: (C)1996,JPO