Phase relations and vitrification in saccharide-water solutions and the trehalose anomaly

Glass transition temperatures and phase relations for several saccharide-water systems are reported. The trehalose-water system is distinguished from the others by a significantly higher T_g at all water contents with a particularly large advantage near the stoichiometry of one water molecule per glucose ring. We relate this to the observation that desert insects, which survive dehydration and can exist in suspended animation for decades (presumably in the vitreous state), produce trehalose intracellularly during desiccation.