Chang Hongmiao, Zhang Junwei, Xia Jian, Kang Caiyun, Yan Yueming
Beijing Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement, College of Life Science, Capital Normal University, 100048 Beijing, China.
Beijing Key Laboratory of Plant Gene Resources and Biotechnology for Carbon Reduction and Environmental Improvement, College of Life Science, Capital Normal University, 100048 Beijing, China.
Food Chem. 2021 Dec 24;376:131944. doi: 10.1016/j.foodchem.2021.131944.
This study investigated the influence of wheat waxy proteins on type III resistant starch (RS) formation, molecular structure and physicochemical properties. Waxy deletions led to a significant increase in B- and C-type starch granules, particle size of RS, and slowly digesting starch content, and a decrease in content of amylose and RS. X-ray powder diffraction and Fourier-transform infrared spectroscopy analyses revealed high relative crystallinity and long-range (1047/1022 cm, IR) and low short-range (1022/995, IR) crystalline structures of RS in waxy wheat, which suggests that waxy deletions could produce a more ordered crystalline structure and fewer amorphous regions in RS crystals. Further laser confocal microscopy Raman spectroscopy analysis found that waxy deletions significantly increased the full width at half maximum and intensity of the bands at 480 cm, as well as leading to more ordered RS crystals. These changes in molecular structure resulted in improved physicochemical properties of RS.
本研究调查了小麦蜡质蛋白对III型抗性淀粉（RS）形成、分子结构及理化性质的影响。蜡质缺失导致B型和C型淀粉颗粒显著增加、RS粒径及慢消化淀粉含量增加，直链淀粉和RS含量降低。X射线粉末衍射和傅里叶变换红外光谱分析表明，糯小麦中RS具有较高的相对结晶度以及长程（1047/1022 cm，红外）和较低的短程（1022/995，红外）晶体结构，这表明蜡质缺失可使RS晶体产生更有序的晶体结构和更少的无定形区域。进一步的激光共聚焦显微镜拉曼光谱分析发现，蜡质缺失显著增加了480 cm处谱带的半高宽和强度，同时导致RS晶体更有序。这些分子结构的变化导致RS的理化性质得到改善。
