Question

In addition to lactose, how many other heterodisaccharides can D-galactose and D-glucose form?

Short answer

19 different disaccharides are formed from D-galactose and D-Glucose. D-glucopyranose forms 19 different disaccharides with their α and β forms. In the same manner, the D-galactose and D-glucose form 19 different heterodisaccharides for their pyranose form.

Step-by-step solution

Lactose

Lactose is a disaccharide sugar linked by one molecule of galactose and one molecule of glucose and the link is β (1→4).

Heterodisaccharides from D-galactose and D-glucose

D-galactopyranose and D-glucopyranose form 19 different heterodisaccharides.

19 different heterodisaccharides are formed by D-galactose and D-glucose.