| Abstract
| - The structural properties resulting from the reciprocal influence between water and three well-knownhomologous disaccharides, namely, trehalose, maltose, and sucrose, in aqueous solutions have been investigatedin the 4−66 wt % concentration range by means of molecular dynamics computer simulations. Hydrationnumbers clearly show that trehalose binds to a larger number of water molecules than do maltose or sucrose,thus affecting the water structure to a deeper extent. Two-dimensional radial distribution functions of trehalosesolutions definitely reveal that water is preferentially localized at the hydration sites found in the trehalosedihydrate crystal, this tendency being enhanced when increasing trehalose concentration. Over a rather wideconcentration range (4−49 wt %), the fluctuations of the radius of gyration and of the glycosidic dihedralangles of trehalose indicate a higher flexibility with respect to maltose and sucrose. At sugar concentrationsbetween 33 and 66 wt %, the mean sugar cluster size and the number of sugar−sugar hydrogen bonds formedwithin sugar clusters reveal that trehalose is able to form larger clusters than sucrose but smaller than maltose.These features suggest that trehalose−water mixtures would be more homogeneous than the two others, thusreducing both desiccation stresses and ice formation.
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