The Effect of Radiation on Carbohydrates

Depolymerization of cellulose fibers during irradiation is accompanied by a reduction in crystallinity, and, at high doses, extensive decomposition occurs. A dose of 5 X 10 equivalent roentgens brings about marked degradation and is sufficient to convert cotton linters into water-soluble materials. After irradiation, cellulose is more susceptible to acid hydrolysis and exhibits an after-effect. When irradiation is terminated, the intrinsic viscosity of cupriethylenediamine solutions of the irradiated cellulose continues to decrease. This behavior is initiated by oxygen and terminated by water. A similar effect is encountered with pectins after irradiation. 

The irradiation of dextran in the solid state and in solution has been studied in detail. When dry, native dextran of high molecular weight (from Leuconoatoc mesenteroides) is irradiated with 800 KV peak electrons, the initial, molecular weight amounting to several million is diminished to about 

Unbranched, six-carbon sugars and their derivatives are considerably more stable toward ionizing radiations in the solid state than in solution. This behavior could be anticipated, since recombination of radicals initially formed by irradiation, aided by the cage effect of the lattice, would reduce the extent of the reaction with the solids, compared with similar 

The precise nature of the chemical changes have been examined in detail for irradiations of aqueous solutions only. Oxygen exerts an important influence on the nature of the products, and, in radiation-chemical studies on carbohydrates, it is therefore essential to maintain either evacuated or oxygenated conditions throughout a particular irradiation. If initially air-equilibrated solutions are used, and no provision is made for re- 

Constituents Present in Aqueous o-Mannose Solutions After Irradiation with Co y-rays 

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