1963 年 83 巻 10 号 p. 956-960
Starch was oxidized with nitric acid under various conditions and the amount of glucuronic acid residue (I), non-uronyl carboxyl group (II), and carbonyl groups (III) of free aldehyde and ketone groups was determined in the oxidized starch. I was determined by the continuous furfural extraction method, II was calculated from the difference of total acid radical by alkali titration and that based on the amount of I, and III was calculated from the amount of hydrogen consumed in sodium borohydride reduction. Free aldehyde group was determined by sodium chlorate oxidation.
It was thereby revealed that nitric acid oxidation of starch effects oxidation of secondary alcohol as well as primary alcohol, the maximum of glucuronic acid residue in oxidized starch being ca. 50%. Low-temperature oxidation with high concentration of nitric acid is marked by formation of carbonyl group and high-temperature oxidation with low concentration of nitric acid, non-uronyl carboxyl group.