School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
Department of Biotechnology and Food Engineering, Guangdong Technion-Israel Institute of Technology, 241 Daxue Road, Shantou, Guangdong, China; Faculty of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa 3200003, Israel.
Int J Biol Macromol. 2023 Jul 1;242(Pt 4):125105. doi: 10.1016/j.ijbiomac.2023.125105. Epub 2023 May 29.
Investigation on amylopectin molecular structure is gaining importance for understanding starch property. Lotus seeds are a novel starch source with high apparent amylose content. Current understanding on the molecular structure of amylopectin in lotus seed starch is scarce. This study compared the molecular structure of a range of lotus seed amylopectins with those of maize and potato amylopectins. Internal structures of these amylopectins were compared via investigating the chain length distribution of their β-limit dextrins. The average lengths and molar compositions of unit chains in lotus seed amylopectins and their β-limit dextrins fell generally between those of maize and potato. The average chain lengths of lotus seed, maize, and potato amylopectins were 19.95 (on average), 19.11, and 21.19 glucosyl residues, respectively. Lotus seed amylopectins had higher weight proportion of clustered unsubstituted chains (44.94 % on average) than those of potato (43.99 %) and maize amylopectins (42.95 %). Results of correlation analysis indicated that apparent amylose content of LS was related to structural characteristics of its amylopectin due to the presence of long external chains. The results of this study are of fundamental importance for the utilization of lotus seed starch as a novel starch source.
研究支链淀粉的分子结构对于理解淀粉性质具有重要意义。莲子是一种具有高直链淀粉含量的新型淀粉来源。目前对莲子淀粉中支链淀粉的分子结构了解甚少。本研究比较了一系列莲子支链淀粉与玉米和马铃薯支链淀粉的分子结构。通过研究其β-极限糊精的链长分布，比较了这些支链淀粉的内部结构。莲子、玉米和马铃薯支链淀粉及其β-极限糊精的单元链平均长度和摩尔组成通常介于玉米和马铃薯之间。莲子、玉米和马铃薯支链淀粉的平均链长分别为 19.95（平均）、19.11 和 21.19 个葡萄糖基残基。莲子支链淀粉的无取代簇链的重量比例（平均为 44.94%）高于马铃薯（43.99%）和玉米支链淀粉（42.95%）。相关分析结果表明，由于长的外部链的存在，LS 的直链淀粉含量与其支链淀粉的结构特征有关。本研究结果对将莲子淀粉作为一种新型淀粉来源的利用具有重要意义。
