4-Nitrophenyl b-D-cellotetraoside

4-Nitrophenyl b-D-cellotetraoside is a chromogenic substrate utilized for the detection and quantification of cellulase enzyme activity. Cellulase enzymes hydrolyze the β-1,4-glycosidic bonds of cellulose, a major component of plant cell walls. Upon cleavage by cellulase, it releases 4-nitrophenol, a compound that exhibits a yellow color and absorbs strongly at 405 nm, allowing for easy spectrophotometric measurements of cellulase activity levels in various sample types, including bacterial and fungal cultures, environmental samples, and industrial applications.

4-Nitrophenyl β-D-cellotetraoside is small molecule cellulose mimic that consists of a tetramer of D-glucose units joined by β-1-4-glycosidic bonds. An aglycosidic bond links a 4-nitrophenyl moiety to the anomeric carbon of the first glucose unit. 4-Nitrophenyl β-D-cellotetraoside is employed in cellulose degradation studies to determine the specificity of cellulases. The defined, small, and soluble structure of 4-nitrophenyl β-D-cellotetraoside makes it well suited for these studies. Its fragmentation pattern after enzymatic digestion can be analyzed by TLC or by release of 4-nitrophenol which exhibits strong absorbance at 395 nm in alkaline solution.