Tianjin Key Laboratory of Food Biotechnology, School of Biotechnology and Food Science, Tianjin University of Commerce , Tianjin 300134, People's Republic of China.
J Agric Food Chem. 2015 Feb 11;63(5):1562-72. doi: 10.1021/jf503203r. Epub 2015 Feb 3.
The retrogradation of rice in shelf life is the biggest barrier to the industrial production of traditional foods using rice as material. Many rice breeders have tried their best to screen low-retrogradation rice cultivars without a specific indicator. To identify the main retrogradation-related properties of rice, the starch, amylose, and amylopectin from 16 rice cultivars were extracted from rice powder and their physicochemical properties, such as visible absorbance, infrared, average molecule weight (amylopectin), chain-length distribution (amylopectin), X-ray diffraction, and differential scanning calorimetry, were determined. The correlation between starch retrogradation rates and those physicochemical properties was investigated. The results show that a significant positive correlation (R(2) = 0.85; r = 0.926; p < 0.01) exists only between proportions of the chains [degree of polymerization (DP) > 10] in amylopectin and the retrogradation rates of different rice starches. The findings in the paper offer a shortcut for rice breeders to screen cultivars with a low retrogradation rate. Because the genes related to the branching enzyme control the DP of amylopectin, they can be exploited as molecular markers to screen low-retrogradation rice cultivars.
在货架期内，大米回生是利用大米作为原料生产传统食品的最大障碍。许多水稻育种家已经尽力筛选回生率低的水稻品种，但没有具体的指标。为了确定大米回生的主要相关特性，从 16 个水稻品种的米粉中提取淀粉、直链淀粉和支链淀粉，并测定其理化特性，如可见吸光度、红外、平均分子量（支链淀粉）、链长分布（支链淀粉）、X 射线衍射和差示扫描量热法。研究了淀粉回生率与这些理化特性之间的相关性。结果表明，直链淀粉和支链淀粉的回生率与支链淀粉中链段[聚合度（DP）>10]的比例之间仅存在显著的正相关（R（2）=0.85；r=0.926；p<0.01）。本研究为水稻育种家筛选回生率低的品种提供了一条捷径。因为与分支酶相关的基因控制支链淀粉的 DP，所以可以将它们作为分子标记来筛选低回生率的水稻品种。
