|Nothnagel, Eugene - UCR,DEPT. OF BOT./PL.SCI.|
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: November 17, 2005
Publication Date: November 1, 2006
Citation: Yadav, M.P., Nothnagel, E.A. 2006. Chemical and composition of an effective emulsifier subfraction of gum arabic. Book Chapter 16, in ACS Symposium Series 935, Advances in Biopolymers Molecules, Clusters, Networks, and Interactions, Eds. M. L. Fishman, P. X. Qu, L. Wisker, p.243-254. Technical Abstract: Gum arabic, which is principally a mixture of polysaccharides and arabinogalactan-proteins (AGPs), contains trace levels of lipids. This report explores the hypothesis that these lipids are attached to the gum arabic AGPs as glycosyl-phosphatidylinositol (GPI) lipids, or in some other way, and make a significant contribution to the emulsifying properties of gum arabic. Treatment of gum arabic with nitrous acid, which cleaves the GPI oligosaccharide, decreased the emulsion stabilizing capacity of gum arabic. Treatment with 50% aqueous HF at 0oC resulted in diminished emulsion stabilizing properties of gum arabic but also significantly reduced the arabinose content of the gum. The approximately 1-3% subfraction of gum arabic components that adsorb at the surface of oil droplets had higher abundance of GPI linker components and much higher relative lipid content than the whole gum.