Monitoring the stability of heparin: NMR evidence for the rearrangement of sulfated iduronate in phosphate buffer.

Heparin, a major anticoagulant drug, comprises a complex mixture of motifs. Heparin is isolated from natural sources while being subjected to a variety of conditions but the detailed effects of these on heparin structure have not been studied in depth. Therefore, the result of exposing heparin to a range of buffered environments, ranging pH values from 7 to 12, and temperatures of 40, 60 and 80 °C were examined.

Hydrolytic Degradation of Heparin in Acidic Environments: Nuclear Magnetic Resonance Reveals Details of Selective Desulfation.

Heparin is a complex glycosaminoglycan, derived mainly from pig mucosa, used therapeutically for its anticoagulant activity. Yet, owing largely to the chain complexity, the progressive effects of environmental conditions on heparin structure have not been fully described. A systematic study of the influence of acidic hydrolysis on heparin chain length and substitution has therefore been conducted.

Thermal degradation and stability of sodium hyaluronate in solid state.

The kinetics and mechanism of depolymerisation of solid sodium hyaluronate at elevated temperatures and various pH have been investigated. Depolymerisation was found to be governed by random chain scission. The activation energy at neutral pH was found to be 127 kJ/mol.

Evidence of the presence of 2-O-beta-D-xylopyranosyl-alpha-l-arabinofuranose side chains in barley husk arabinoxylan.

(Glucurono)arabinoxylans were extracted from barley husks and degraded with endo-beta-xylanase or subjected to periodate oxidation. The released oligosaccharide fragments were separated and isolated on Biogel-P2, and their structures were determined by NMR spectroscopy. The oligosaccharides identified consisted of beta-d-(1-->4)-linked xylopyranosyl residues, of which some were substituted at O-3 with alpha-l-arabinofuranosyl groups or at O-2 with 4-O-methylglucuronic acid.