Figure 1.

Inhibition of recombinant acid β-glucosidase (β-Glu). Endpoint enzyme activity measurement was recorded in the presence of different concentrations of isofagomine (IFG) (a), ambroxol (ABX) (b), and bromohexine (BHX) (c) after a 20 min incubation phase using 1.5 mM 4-methylumbelliferyl-β-D-glucopyranoside (4-MUG) synthetic substrate at pH 4.7. (d) IC₅₀ was calculated from the dose–response curves using the function “log(inhibitor) vs. response” (GraphPad Prism 5 for Windows, GraphPad Software, La Jolla, CA, USA).