Abstract
A new enzymatic method to determine cyclodextrins was described in this paper. The principle of the method consists of the combination of specific enzyme actions and the determination of reducing value. Cyclodextrins do not show any reducing value, because of no reducing end. In a mixture containing maltosaccharides, a and ?A-cyclodextrin, glucoamylase hydrolyses only maltosaccharides. Reducing value was determined by Somogyi-Nelson method after degradation of maltosaccharides to glucose (GAV). Total cyclodextrin content was obtained by subtraction GAV from total sugar (PS) which was determined by the phenol-H2SO4 method. Aspergillus oryzae α-amylase hydrolysed fast β-cyclodextrin and extremely slow α-cyclodextrin. β-Cyclodextrin and maltosaccharides were degraded to glucose by the combination of glucoamylase and Aspergillus oryzae a-amylase (reducing value of this enzyme system: GTV). Therefore, a-cyclodextrin content was obtained by subtracting GTV from PS, correction of a-cyclodextrin degradation should be done if necessary. Cyclodextrins were determined by this enzymatic method within the relative error of 5% in the mixture of cyclodextrins and oligosaccharides.
