Binding of cyclic compounds by starch cryotextures from aqueous solutions

Abstract

Binding of cyclohexanol, 2-, 3-, and 4-methylcyclohexanones, and isomeric fenchone and camphor bicycles by the corn starch cryotextures from aqueous solutions in a concentration range of 1—16 mmol L^–1 was studied using capillary gas chromatography. Cyclohexanone is not sorbed by the cryotexture. All substances except fenchone exhibit linear plots of the amount of substances bound by the cryotexture vs.their concentration in the corn starch gel. The empirical constants in the linear dependence of the concentration of cryotexture-bound odorants on their initial concentration in the gel were calculated. The presence and position of methyl substituents in the ring affect the degree of binding of the cyclic compounds. The sorption isotherms of the cycles have different shapes. The apparent binding constants and the number of binding sites were determined for compounds reaching the saturation stage on sorption. Cooperative interactions between the binding sites were found. The most part of compounds are irreversibly bound by the cryotexture pointing to the formation of supramolecular complexes.