Synthesis and use of p-nitrophenyl-2-O-(α-l-fucopyranosyl)-β-d-galactopyranoside for the rapid detection of substrate-specific α-l-fucosidases

A novel synthetic chromogenic substrate, Fuc α1 → 2Gal β1 → OC₆H₄NO₂(p), was used for the rapid assay of α-l-fucosidases which hydrolyze the glycosidic linkage, Fuc α1 → 2Gal. The procedure is based on the sequential action of α-l-fucosidase and an exogenously added exo-β-d-galactosidase to release the easily measurable p-nitrophenol moiety. This method detected α-l-fucosidases from Aspergillus niger, Clostridium perfringens, and almond which are known to hydrolyze the α1 → 2 linkage specifically. The advantages of this procedure over procedures previously used for the detection of substrate-specific α-l-fucosidases are discussed.