betaDglucosidic

Beta-D-glucosidic refers to a type of glycosidic linkage in which a β-D-glucose residue is connected to another sugar or to a non-sugar aglycone through the anomeric carbon (C1) of glucose. The beta (β) configuration at C1 distinguishes these bonds from alpha (α) linkages. In describing a compound as having a beta-D-glucosidic bond, glucose acts as the glycone and the attached moiety as the aglycone; the exact linkage position can vary (for example, β-1,4 in certain disaccharides, or β-1,6 in others).

The most familiar context is glycosides containing a β-D-glucosyl group. In disaccharides, a classic example is cellobiose, where two glucose units are linked by a β-1,4 bond. In natural products, many plant glycosides are β-D-glucosides, such as arbutin (hydroquinone β-D-glucoside) and salicin (salicyl alcohol β-D-glucoside). Polysaccharides like cellulose consist of long chains of β-D-glucose units linked by β-1,4 glycosidic bonds.

Enzymatically, β-D-glucosidic bonds are cleaved by beta-glucosidases, enzymes that hydrolyze the bond to release glucose and the corresponding aglycone. In digestion and metabolism, such hydrolysis activates or liberates aglycone compounds and terminates glucoside storage, solubility, and transport roles of many plant-derived molecules.

Biological significance includes increasing solubility and stability of hydrophobic aglycones through glycosylation, with subsequent release via hydrolysis. The concept is contrasted with alpha-D-glucosidic bonds, where the anomer configuration at C1 is alpha.