Explain the Digestion of carbohydrates?

You are aware that 60-70% of energy is supplied by the dietary carbohydrates which are primarily present as polysaccharides (starch) followed by disaccharide and free monosaccharide. But the monosaccharides are present in very small amounts in our diet. To be absorbed from the gut, these carbohydrates must be broken down to their constituent monosaccharide units. Let us now briefly review how these carbohydrates are digested in the gut.

Figure: Digestion of carbohydrates

The hydrolytic enzymes involved in the digestion of carbohydrates are collectively called 'glycosidases' or 'carbohydrases'. The major carbohydrates enzyme secreted by the salivary glands and the acinar cells of the pancreas is the endo-glycosidase - amylase. This enzyme hydrolyzes a-1, 4-linkages in amylose and amylopectin to yield maltose, maltotriose and dextrins. The further hydrolysis of these and dietary sucrose and lactose are brought about by 'oligosaccharidases', which are expressed on the apical membrane of the epithelial cells on the small intestinal villi.