Institute of Non-Ferrous Metals, ulica Sowinskiego 5, 44-100 Gliwice, Poland.
J Phys Condens Matter. 2013 Sep 18;25(37):375101. doi: 10.1088/0953-8984/25/37/375101. Epub 2013 Aug 14.
The sugar specific mutarotation reaction in biologically important L-fucose and its enantiomer in the pure, anhydrous, supercooled liquid state has been studied. Kinetics measurements in the temperature range 313-328 K at ambient pressure have been performed by means of dielectric spectroscopy, a method widely used for studying the molecular dynamics of glass-forming liquids. The kinetic curves have been obtained by tracking the equilibration process in sugar melted and quenched to the desired temperature. Thereafter, an activation energy equal to Ea = 140 kJ mol(-1) for D-fucose and Ea = 123 kJ mol(-1) for L-fucose has been derived from the Arrhenius fit of temperature dependent rate constants. It was also shown that the kinetics curves at the lowest temperatures studied have sigmoidal shape, which was connected to the high concentration of furanosidic forms.
已研究了在生物学上重要的 L-岩藻糖及其对映体在纯无水过冷液体状态下的糖特异性差向旋光反应。通过介电谱法在环境压力下的 313-328 K 温度范围内进行了动力学测量，介电谱法是一种广泛用于研究玻璃形成液体分子动力学的方法。通过跟踪糖熔化并淬火至所需温度的平衡过程获得了动力学曲线。此后，从温度相关速率常数的阿仑尼乌斯拟合中得出 D-岩藻糖的活化能等于 Ea = 140 kJ mol(-1)，L-岩藻糖的活化能等于 Ea = 123 kJ mol(-1)。还表明，在所研究的最低温度下的动力学曲线呈 S 形，这与呋喃糖形式的高浓度有关。
