Key Laboratory of Analytical Science and Technology of Hebei Province, College of Chemistry and Environmental Science, Hebei University, Baoding 071002, China.
Key Laboratory of Analytical Science and Technology of Hebei Province, College of Chemistry and Environmental Science, Hebei University, Baoding 071002, China; Affiliated Hospital of Hebei University, Baoding 071000, China.
Food Chem. 2021 Jul 1;349:129168. doi: 10.1016/j.foodchem.2021.129168. Epub 2021 Jan 26.
Insight into the structure and conformation characteristics of starch that influence its enzyme susceptibility is import for its potential application. In this study, the capacity of asymmetrical flow field-flow fractionation (AF4) coupled online with multi-angle light scatting (MALS) and differential refractive index (dRI) detectors (AF4-MALS-dRI) for monitoring of change in structure and conformation of potato starch during enzymatic hydrolysis was evaluated. The dissolution behavior of potato resistant starch (type 2) (PRS) was investigated. The effect of incubation time and amyloglucosidase concentration on the structure and conformation of potato starch was studied. The apparent density and the ratio of R (radius of gyration) to R (hydrodynamic radius) obtained from AF4-MALS-dRI were proven to be important parameters as they offer an insight into conformation of PRS at molecular level. Results suggested that gelatinization process made potato amylose molecules have a loose and random coil conformation which could contribute to an acceleration of enzymatic hydrolysis of potato starch. Furthermore, an intermediate with an elongated branched conformation was found between amylose and amylopectin populations, which may play a role in digestion property of potato starch. The results demonstrated that AF4-MALS-dRI is a powerful tool for better understanding of conformation of PRS.
深入了解影响淀粉酶敏感性的结构和构象特征对于其潜在应用至关重要。在这项研究中，评估了不对称流场流分离（AF4）与多角度光散射（MALS）和差示折射指数（dRI）检测器在线联用（AF4-MALS-dRI）监测酶解过程中马铃薯淀粉结构和构象变化的能力。研究了马铃薯抗性淀粉（类型 2）（PRS）的溶解行为。研究了孵育时间和糖化酶浓度对马铃薯淀粉结构和构象的影响。从 AF4-MALS-dRI 获得的表观密度和 R（回转半径）与 R（流体力学半径）之比被证明是重要的参数，因为它们提供了 PRS 在分子水平上构象的深入了解。结果表明，糊化过程使马铃薯直链淀粉分子具有松散和随机卷曲构象，这可能有助于加速马铃薯淀粉的酶解。此外，在直链淀粉和支链淀粉群体之间发现了具有伸长支化构象的中间产物，它可能在马铃薯淀粉的消化特性中起作用。结果表明，AF4-MALS-dRI 是更好地了解 PRS 构象的有力工具。
