Structural and thermodynamic properties of rice starches with different genetic background. Part 2. Defectiveness of different supramolecular structures in starch granules
Structural and thermodynamic properties of rice starches with different genetic background. Part 2. Defectiveness of different supramolecular structures in starch granules
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DOI：
10.1016/j.ijbiomac.2007.07.005
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发表时间：
2007-12-01
影响因子：
8.2
通讯作者：
Yuryev, Vladimir P.
中科院分区：
文献类型：
--
作者：
Koroteeva, Dasha A.;Kiseleva, Valentina I.;Yuryev, Vladimir P.
采用高灵敏度差示扫描量热法（HSDSC）、小角X射线散射（SAXS）、光学显微镜（LM）和扫描电子显微镜（SEM）等技术，研究了11个不同直链淀粉和支链淀粉缺陷程度的泰国水稻品种淀粉中不同超分子结构的缺陷程度。尽管支链淀粉大分子的链长分布和淀粉中直链淀粉的水平不同，但结晶片、支链淀粉簇和颗粒的大小不变。对天然淀粉的DSC、SAXS、LM和SEM数据的综合分析，以及天然淀粉和退火淀粉的热力学数据的比较，允许确定缺陷的结构和直链淀粉链在结晶和无定形薄片中的定位，薄片、簇和颗粒的缺陷。结果表明，直链淀粉的“连接链”、位于结晶片层中的直链淀粉-脂质复合物、无定形片层中悬挂在微晶上的双螺旋链的缺陷端（“悬挂”链）以及DP为6-12和25-36的支链淀粉链都可以被认为是缺陷。它们的积累可导致残余颗粒的形成。在淀粉中支链淀粉链结构和直链淀粉含量中观察到的变化反映在层状、簇状和颗粒水平上的结构组织的相互关联的改变中。(C)2007 Elsevier B. V.保留所有权利。
High-sensitivity differential scanning microcalorimetry (HSDSC, small-angle X-ray scattering (SAXS), light (LM) and scanning electronic (SEM) microscopy techniques were used to study the defectiveness of different supramolecular structures in starches extracted from 11Thai cultivars of rice differing in level of amylose and amylopectin defects in starch crystalline lamellae. Despite differences in chain-length distribution of amylopectin macromolecules and amylose level in starches, the invariance in the sizes of crystalline lamellae, amylopectin clusters and granules was established. The combined analysis of DSC, SAXS, LM and SEM data for native starches, as well as the comparison of the thermodynamic data for native and annealed starches, allowed to determine the structure of defects and the localization of amylose chains in crystalline and amorphous lamellae, defectiveness of lamellae, clusters and granules. It was shown that amylose "tie chains", amylose-lipid complexes located in crystalline lamellae, defective ends of double helical chains dangling from crystallites inside amorphous lamellae ("dangling" chains), as well as amylopectin chains with DP 6-12 and 25-36 could be considered as defects. Their accumulation can lead to a formation of remnant granules. The changes observed in the structure of amylopectin chains and amylose content in starches are reflected in the interconnected alterations of structural organization on the lamellar, cluster and granule levels. (C) 2007 Elsevier B.V. All rights reserved.