Further evidence for detection of short-lived transient hypomanganate(V) and manganate(VI) intermediates during oxidation of some sulfated polysaccharides by alkaline permanganate using conventional spectrophotometric techniques

Ishaq A Zaafarany; Abd Alla S N AlArifi; Ahmed Fawzy; Gamal A Ahmed; Said A Ibrahim; Refat M Hassan; Hideo D Takagi

doi:10.1016/j.carres.2010.04.013

Further evidence for detection of short-lived transient hypomanganate(V) and manganate(VI) intermediates during oxidation of some sulfated polysaccharides by alkaline permanganate using conventional spectrophotometric techniques

Carbohydr Res. 2010 Jul 19;345(11):1588-93. doi: 10.1016/j.carres.2010.04.013. Epub 2010 Apr 29.

Authors

Ishaq A Zaafarany¹, Abd Alla S N AlArifi, Ahmed Fawzy, Gamal A Ahmed, Said A Ibrahim, Refat M Hassan, Hideo D Takagi

Affiliation

¹ Chemistry Department, Faculty of Applied Sciences, Umm Al-Qura University, Makkah Al-Mukarramah, Saudi Arabia.

PMID: 20557874
DOI: 10.1016/j.carres.2010.04.013

Abstract

Spectrophotometric evidence for the formation of hypomanganate(V), [CAR-Mn(V)O43-], and manganate(VI), [CAR-Mn(VI)O42-], intermediate complexes has been confirmed during the oxidation of iota- and lambda-carrageenan-sulfated polysaccharides (CAR) by alkaline permanganate at pHs 12 using a conventional spectrophotometer. These short-lived intermediate complexes were identified and characterized. A reaction mechanism in good consistence with the experimental results is suggested.

MeSH terms

Absorption
Carrageenan / chemistry
Hydrogen-Ion Concentration
Kinetics
Manganese Compounds / analysis*
Manganese Compounds / chemistry*
Oxidation-Reduction
Oxides / analysis*
Oxides / chemistry*
Polysaccharides / chemistry*
Spectrophotometry
Sulfuric Acids / chemistry*

Substances

Manganese Compounds
Oxides
Polysaccharides
Sulfuric Acids
permanganic acid
Carrageenan
sulfuric acid