Effect of Acetylation on Physico-chemical Characteristics of Sweitenia mycrophylla Gum:A Potential Excipient.

Abstract

Recent studies focus on the chemical modification of polysaccharides for biomedical applications. Chemical modification of these polysaccharides produces products with improved physicochemical and functional properties that are not available from commercial polysaccharides. The modification discussed includes acetylation of Sweitenia mycrophylla gum with acetic anhydride in the presence of sodium hydroxide. The resulting product was characterized by FTIR and NMR spectroscopy. The degree of acetylation is 0.24. Physicochemical characteristics such as solubility, viscosity and swelling index of the native Sweitenia mycrophylla gum and acetylated gum were also determined. The results showed that the acetylated gum had higher values of solubility, viscosity and swelling index as 93.40% at 80oC, 65.4cs and 46.54% respectively while the native gum had solubility viscosity and swelling index as 30.10% at 80oC, 28.40cs and 15.20% respectively. Chemical modification via acetylation increased the solubility, viscosity and swelling index of Sweitenia mycrophylla gum. The experimental work provides enough evidence to exploit this natural biopolymer in food, textile and pharmaceutical industry, especially as an efficient alternative approach for the oral delivery of hydrophilic macromolecules.