Abstract
The kinetics of oxidation of iota- and lambda-carrageenan polysaccharides by alkaline permanganate have been investigated spectrophotometrically. A kinetic evidence for the formation of 1:1 intermediate complexes is revealed. The products were
keto-acid oxidation derivative and were identified by IR spectra and elemental analysis.
Spectrophotometric evidence for the formation of hypomanganate(V), [CAR-
Mn
V
O
4
3
-
], and manganate(VI), [CAR-
Mn
VI
O
4
2
-
], 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.