A HEWL (Hen egg white lysozyme) orthorhombic crystal is grown by the two liquid interface method. The dynamics in a gigahertz range is measured over the wide temperature range in cryoprotective glycerol and propylene glycol aqueous solutions by using micro-Brillouin scattering. The elastic anomaly and structural relaxation are clearly observed. The structural relaxation time is assumed that it obeys Debye relaxation model. The temperature dependence of the relaxation time obeys the Arrhenius law at low temperatures. The correlation is found between the activation energy ΔE and the pre-exponential factor τ_0. The log τ_0 vs. ΔE plot indicates that the Mayer-Neldel rule holds.
