X Glucoside [5 Bromo 4 Chloro 3 indolyl β-D-glucopyranoside], 1 g is a chromogenic substrate used in biochemical assays for the detection of β-D-glucosidase activity. Upon hydrolysis by the enzyme, it produces a colored compound that can be quantified spectrophotometrically. This substrate is commonly employed in microbiological studies, particularly for identifying bacteria or yeasts that express β-D-glucosidase. It serves as a valuable tool in enzyme assays and screening processes for the presence of specific metabolic enzymes. X Glucoside is frequently used in research, including genetic studies, enzyme characterization, and microbiological diagnostics.