School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand.
School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand.
Carbohydr Polym. 2019 May 15;212:40-50. doi: 10.1016/j.carbpol.2019.02.028. Epub 2019 Feb 11.
The effects of amyloglucosidase digestion on the multi-scale supramolecular structural changes of native corn starch were examined by ultra-small angle neutron scattering (USANS), small angle X-ray scattering (SAXS), particle sizing, and scanning electron microscopy (SEM). Well-defined and spherical pores were formed upon amyloglucosidase digestion as revealed by SEM. The pore polydispersity was determined using USANS by assuming spherical pore morphology with log-normal distribution. Both USANS and SEM measurements demonstrated that the pores become larger and more polydisperse as the digestion time increased. Moreover, SAXS revealed that the lamellar peak area decreased gradually for both thermally and enzymatically treated starches, indicating partial loss of lamellar organisation. Overall, the results demonstrate structural changes occur on multiple length scales upon enzymatic digestion from granular to lamellar with small-angle scattering demonstrated to provide detailed characterization of the resultant microporous structures.
采用超小角中子散射（USANS）、小角 X 射线散射（SAXS）、粒度分析和扫描电子显微镜（SEM）研究了支链淀粉酶消化对天然玉米淀粉多尺度超分子结构变化的影响。SEM 揭示，淀粉酶消化后形成了规则且呈球形的孔。采用 USANS 并假设球形孔形态的对数正态分布，可确定孔的多分散性。USANS 和 SEM 测量均表明，随着消化时间的增加，孔变得更大且多分散性更大。此外，SAXS 表明，热和酶处理的淀粉的层状峰面积逐渐减小，表明层状组织部分丧失。总的来说，这些结果表明，酶消化会导致结构发生从颗粒到层状的多尺度变化，小角散射被证明可对所得微孔结构进行详细表征。
