A fluorescence assay for enzymes that cleave glycosidic linkages to produce reducing sugars

A rapid, facile, and sensitive assay has been developed for enzymes that generate reducing sugars. The assay is a modification of a method for post-HPLC column derivatization and detection of reducing sugars and is carried out in a single test tube. The assay is useful for large numbers of samples, such as those produced during purification of enzymes. Less than 500 pmol of reducing sugar can be quantitatively measured. The assay reported here is at least 10 times more sensitive than either the commonly employed parahydroxybenzoic acid hydrazide method or the recently reported bicinchoninate method, and 50 times more sensitive than the Nelson-Somogyi method.