||α-L-Fucosidase (EC 220.127.116.11) (FUCA1) is a hydrolase that is able to cleave the α-L-fucosyl moieties from glycoconjugates and oligosaccharides. Fucosidase plays a pivotal role in cell differentiation, apoptosis, inflammation and host-pathogen interaction. Furthermore, abnormal concentrations of this glycosidase have been observed in patients suffering from cancer, fucosidosis, rheumatoid arthritis, cystic fibrosis, and leukocyte adhesion deficiency. Industrial applications of FUCA1 include synthesis of fucosylated analogs that could serve as antiadhesion compounds, cancer vaccines, and anti-inflammatory therapeutics. α-L-Fucosidase Assay Kit provides a simple, sensitive and high-throughput adaptable approach to detect physiological concentrations of this glycosidase in a variety of biological samples. In this assay, FUCA1 uses a synthetic 4-MUF substrate and releases a fluorescent methylumbelliferyl derivative (4-MU) that can be measured kinetically under acidic conditions (Ex/Em = 330/450 nm). The assay is a single-step reaction, with minimal sample preparation. The assay can detect less than 1 μU/ml of FUCA1 activity in serum samples.