A new study of iodine complexes of oxidized gum arabic: An interaction between iodine monochloride and aldehyde groups. (15th January 2018)

• Record Type: Journal Article
• Authors: Ali, Akbar; Ganie, Showkat Ali; Mazumdar, Nasreen
• Is Part Of: Carbohydrate polymers. Volume 180(2018)
• Page Start: 337
• Page End: 347
• Publication Date: 2018-01-15
• Subjects: Gum arabic -- Oxidized gum arabic -- Iodine-gum arabic complexes -- Iodide ions -- Iodine monochloride; Polysaccharides -- Periodicals; Polysaccharides -- Periodicals; Polysaccharides -- Périodiques; Electronic journals; 547.78
• DOI: 10.1016/j.carbpol.2017.10.005
• Languages: English
• ISSNs: 0144-8617

Abstract

Graphical abstract: Highlights: Gum arabic was oxidized with periodate to generate dialdehyde groups in the chains. The aldehyde groups in oxidized GA reacted with ICl and I2 forming iodine complexes. The experimental and spectral data showed addition of ICl molecules to CHO groups. ICl treated oxidized gum released iodide, the nutritional form of iodine, in H2 O. Abstract: Gum arabic, a plant polysaccharide was oxidized with periodate to produce aldehyde groups by the cleavage of diols present in the sugar units. The oxidized gum was then iodinated with iodine monochloride (ICl) and the interaction between electrophilic iodine, I + and reactive carbonyl groups of the modified gum was studied.Results of titrimetric estimation performed to determine the extent of oxidation and aldehyde content in the oxidized gum showed that degree of oxidation ranged between 19.68–50.19% which was observed to increase with periodate concentration; the corresponding aldehyde content was calculated to be 5.15–40.42%. Different strengths of ICl were used to iodinate the oxidized gum and the iodine content of the complexes varied from 6.11–11.72% as determined by iodometric titration. Structure elucidation of the iodine complexes conclusively established the attachment of ICl molecules to CHO groups. A reaction scheme has been proposed suggesting an electrophilic addition of the reagent to the aldehyde groups, a mechanism that was also supported by iodide ion release studies.