All of the following disaccharides are reducing sugars EXCEPT:
A) lactose.
B) maltose.
C) sucrose.
D) cellulose.
E) isomaltose.

Question

Quizplus · Accepted Answer

A reducing sugar is a carbohydrate that is capable of reducing or donating electrons to other molecules. Sucrose is a non-reducing sugar because it has a glycosidic bond between glucose and fructose that prevents it from being able to donate electrons. Lactose and maltose are reducing sugars because they have free anomeric carbons that can donate electrons. Cellulose is not a disaccharide and is not a reducing sugar, as it is a polymer of glucose that is linked by beta-glycosidic bonds, which cannot rotate and therefore cannot form a free anomeric carbon. Isomaltose is a reducing sugar because it has a free anomeric carbon that can donate electrons.

All of the Following Disaccharides Are Reducing Sugars EXCEPT