Acid mucopolysaccharides of frog cartilage in thyroxine-induced metamorphosis

Structural characterization and in vitro antioxidant activities of chondroitin sulfate purified from Andrias davidianus cartilage

Origin and manufacturing process are key factors affecting the biological activities of chondroitin sulfate (CS), which can be utilized as a nutraceutical in dietary supplements. Herein, we extracted and purified CS from the cartilage of artificially breeding Andrias davidianus (ADCS), i.e., Chinese giant salamander (CGS), one of the prospective functional food source materials in China. Low molecular weight CS (LMWADCS) was then prepared by free radical depolymerization of ADCS. High-performance gel permeation chromatography (HPGPC) analysis showed that the average molecular weight (Mw) of ADCS was 49.2 kDa, while the Mw of LMWADCS was 6.4 kDa. After the eliminative degradation of ADCS by chondroitinase ABC, strong anion-exchange high-performance liquid chromatography (SAX-HPLC) analysis showed that the disaccharide composition of ADCS was 14.6% ΔDi0S, 60.9% ΔDi6S and 24.5% ΔDi4S. Then, in vitro antioxidant assays were performed with ADCS, LMWADCS and CS from a commercial source. Our results showed that LMWADCS exerted the highest total antioxidant activity out of the total antioxidant capacity, including the capacity of scavenging DPPH radicals, hydroxyl radicals and superoxide anion radicals. From the results of this study, we can conclude that the Mw and composition of ADCS are different from those reported for bovine and shark CS, and LMWADCS can be utilized as a valuable and potential nutraceutical for the functional food industry.

ISOLATION, CHARACTERIZATION, AND DISTRIBUTION OF ACID MUCOPOLYSACCHARIDES IN RABBIT LEUCOCYTES

Acid mucopolysaccharides have been extracted from whole rabbit polymorphonuclear leucocytes and from the cytoplasmic granules of these cells. The leucocyte acid mucopolysaccharides can be separated into two fractions by the solubility of their CPC complexes in solutions of differing salt concentration. One of these fractions appears to be identical with hyaluronic acid; the other appears to be an atypical chondroitin sulfate. On both a dry weight and total protein basis the polymorphonuclear leucocyte granule contains approximately 2.6 times as much acid mucopolysaccharide as does the whole cell. Hyaluronic acid is concentrated in the granules in particular; its function is unknown. These results do not indicate that all lysosomes contain abundant acid mucopolysaccharides, for no detectable carbohydrate of this class could be extracted from lysosome-rich alveolar macrophages.