State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, China.
Food Chem. 2016 Jul 15;203:530-535. doi: 10.1016/j.foodchem.2016.02.061. Epub 2016 Feb 10.
Branching enzyme (BE, EC 2.4.1.18) was isolated from the developing waxy rice endosperm and used to prepare a highly branched dextrin based on high-amylose maize starch (HAMS) as a substrate. The molecular mass of the starch initially degraded quickly from 2.5 × 10(7) to 4.1 × 10(5)Da, and then stabilized, with a minimal increase during the BE treatment. The resultant branched dextrin had a narrow size distribution, with a mean molecular weight of 5.1 × 10(5)Da and a polydispersity index (PI) of 1.567. The results of high-performance anion exchange chromatography indicated that the degree of polymerization (DP) of the branched chains ranged from 3 to 27; approximately 75.26% of these chains were short (DP<10). These findings suggest that the isolated BE can cleave long chains into oligosaccharides, subsequently transferring oligosaccharides into highly branched dextrins with a narrow size distribution and short side chains.
分支酶（BE，EC 2.4.1.18）从糯稻胚乳中分离出来，并用于以高直链淀粉玉米淀粉（HAMS）为底物制备高度支化的糊精。淀粉最初的降解分子量从 2.5×10（7）迅速降至 4.1×10（5）Da，然后稳定下来，在 BE 处理过程中略有增加。所得的支化糊精具有较窄的分子量分布，重均分子量为 5.1×10（5）Da，多分散指数（PI）为 1.567。高效阴离子交换色谱的结果表明，支化链的聚合度（DP）范围为 3 至 27；这些链中约有 75.26%是短链（DP<10）。这些发现表明，分离的 BE 可以将长链切割成寡糖，然后将寡糖转移到具有较窄分子量分布和短侧链的高度支化糊精中。
