Lactulose (4-o-β-galactopyranosyl-D-fructo-furanose), also known as galactoside fructose, 4-β-D-galactosid-D-fructose and lactulose, contains one molecule of galactose and one molecule of fructose. Lactulose is a kind of synthetic disaccharide formed by base isomerization of lactose catalyzed by free amino group of casein during milk heat treatment.
Lactulose can produce a specific product under the action of enzyme, which reacts with the chromogenic agent to produce a fluorescence product. The excitation wavelength is 530 nm, and the emission wavelength is 590 nm.
