Carbohydrates nonreducing sugars

Selected clay stabilizers are shown in Table 1-10. Thermal-treated carbohydrates are suitable as shale stabilizers [1609-1611]. They may be formed by heating an alkaline solution of the carbohydrate, and the browning reaction product may be reacted with a cationic base. The inversion of nonreducing sugars may be first effected on selected carbohydrates, with the inversion catalyzing the browning reaction. 

Nonreducing sugar (Section 27.9B) A carbohydrate that cannot he oxidized by Tollens, Benedict s, or Fehling s reagent. 

There are many publications and comprehensive handbooks on the thin-layer chromatography (TLC) of carbohydrates (e.g., Refs. 1 and 2). The reason is their great importance in life science and the great diversity of cases monosaccharide, disaccharide, trisaccharide, oligosaccharide, polysaccharide, aldose, ke-tose, triose, tetrose, pentose, hexose, as well as reducing and nonreducing sugars. In addition, when extracted from natural products or produced by fermentation, carbohydrates are accompanied by many impurities. That is why separation methods are used predominantly for their analysis. 

Examination of the active hydrocolloid followed the usual systematic pattern. Proximate analyses were first noted, and then the carbohydrate nature of the components was determined. Galactose was identified as the major product of hydrolysis by oxidation to mucic acid (5, -4, 12, 17) and by optical rotation (17). Glucose (16, 28), fructose (17) or keto sugars (28, UO), pentoses (28, 35), and nonreducing sugars (9) were also found. However, the presence of glucose is attributed by... 

Carbohydrates that contain only acetal groups do not give positive tests with Benedict s or Tollens solutions, and they are called nonreducing sugars. 

Nonreducing sugar (Section 22.6) A carbohydrate containing no amount of an oxidizable aldehyde group. 

---