Alternatively, the Michaelis-Menten approximately obeys a first order kinetics for low substrate concentrations. Surprisingly enough, and despite the fact that this condition is not expected in the conditions of our experiments, our data are well fitted by a network of first order reactions only, including both the anomer exchange and enzymatic oxidation, in all the realizations of our kinetic experiment. One can therefore conclude that the results obtained with our experimental protocol and sample preparation empirically support a pseudo-first order enzyme kinetics, where the catalytic constant is given by the kinetic rate constant k dhβ . Further investigations are underway to shed more light on these aspects.