Extraction of hyaluronic acid from rabbit skin with lanthanum chloride

The defatted rabbit skin was extracted with 0.5 M LaCl3, and the extract was dialyzed exhaustively against distilled water. The precipitate formed during dialysis was dissolved in 28 mM EDTA (ethylenediamine tetraacetate) (pH 7.0). Fr A was obtained from the solution by precipitation with ethanol in the presence of sodium acetate. The results of gel filtration on Sepharose 4B, electrophoresis on cellulose acetate membrane before and after digestion with Streptomyces hyaluronidase, and analytical data indicated that Fr. A was hyaluronic acid with high molecular weight. The present observation together with previous findings suggest that the binding status of proteoglycans in the skin differs significantly from that in cartilages.