Low-molecular weight molluscan glycosaminoglycan from bivalve Katelysia opima (Gmelin)

Heparin, the glycosaminoglycan (GAG), was isolated from mollusk Katelysia opima (bivalve). The crude extract was partially purified by DEAE cellulose fractionation using two different molar concentrations of saline solution. Among the fractions F1, F2, F3 and F4, fraction F3 had highmolecular weight and better activity. F3 was further processed to get low-molecular weight heparin (LMWH) by nitrous acid depolymerization, and the total yield was 1.2 g/kg. The crude unfractionated heparin (UFH), fractionated heparin and depolymerized heparin samples were colorimetrically analyzed for the metachromatic shift using azure-A dye, and all the samples were found to be metachromatically active. Both UFH and LMWH showed an anticoagulant activity of 160 USP U/mg. Fractionated molluscan and LMWH were found to have peaks similar to that of standard heparin when assessed by the FTIR spectrum. Finally, molecular weight was determined by gradient polyacrylamide gel electrophoresis for UFH, fractionated F3 and LMWH, which were found to be 31,000, 30,500 and 6000 Da, respectively.