水分含量对莲子淀粉回生影响及分子动力学模拟分析

采用差示扫描量热仪和X射线衍射仪对不同水分含量的糊化莲子淀粉的回生特性进行研究。结果表明，水分含量是影响淀粉回生的重要因素，其过高或过低对莲子淀粉的老化都有一定的抑制作用；当水分含量70%时，莲子淀粉最易重结晶，体系老化程度最高；分子动力学模拟系统探讨了不同水分含量淀粉老化模型的分子构象、水分子扩散系数、非共价键相互作用等参数的变化，发现在水分含量70%体系中，直链淀粉分子结构更趋于有序化、非共价键相互作用更强，这可在微观层面解释莲子淀粉回生的机理。

Effect of Water Content on the Retrogradation of Lotus Seed Starch and Molecular Dynamics Simulation Analysis

The effect of different water contents on the retrogradation of lotus seed starch was studied by differential
scanning calorimetry (DSC) and X-ray diffractometer (XRD). The experimental results indicated that water content was
a significant factor affecting the retrogradation of starch.and that the aging of starch was inhibited when the water content
was too high or too low. The lotus seed starch was most easily recrystallized with a water content of 70%, and the degree
of retrogradation was highest. The changes in molecular conformation parameters, water diffusion coefficient, and noncovalent
interaction of aging models with different water contents were analyzed using molecular dynamic (MD) simulation
method. It was shown that molecular structure of amylose with water content of 70% tended to be more orderly arranged
and had stronger non-covalent interaction. These observations could explain the mechanism of retrogradation of starch at the
microcosmic level.