Interaction between alkaline phosphatase and ascorbic acid by fluorescence and absorption studies

Very low amounts of ascorbic acid modify alkaline phosphatase fluorescence, absorption and enzymatic activity. A strong quenching of enzyme, tryptophan and tyrosine emission together with evident alterations of the protein absorption characteristics are observed. The catalytic activity inhibition probably reflects a perturbation of the active site environment due to the interaction of ascorbic acid with enzyme aminoacyl residues.