title: Molecular characterization and in vitro digestibility of normal maize starch hydrolyzed by maltotriohydrolase.
abstract: Normal maize starch was hydrolyzed by the glucan 1,4-alpha-maltotriohydrolase (AMTS), and the changes in molecular characteristics and digestibility of starch were evaluated. Upon hydrolysis, maltotriose purity could be modified via controlled AMTS action. The transglycosylation of AMTS possibly happened during the extensive hydrolysis of starch. No single linear association between the z-average radius of gyration (Rz), conformation exponent (ν), apparent molecular density (ρ) and weight average molar mass (Mw) of the starch molecules could be established in the entire process of AMTS hydrolysis. Under mild hydrolysis (≤240 min), Rz and ρ displayed linear relationships with Mw. However, transitions of ν, Rz and ρ appeared after extensive hydrolysis (>240 min), due to the increase in the amount of short chains [degree of polymerization (DP)≤5]. The spherical starch molecule tends toward less compact and a structure between sphere and random coil after extensive hydrolysis. And the increase in the amount of DP≤12 chains and reduction of molecular dimension after AMTS hydrolysis restrict the digestibility of starch. The results of this study suggest that normal maize starch can be modulated by AMTS to produce the desired maltotriose syrup, starch molecular characteristics, and starch digestibility.
authors.affiliation: The State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
authors.forename: Chunsen
authors.initials: C
authors.lastname: Wu
authors.affiliation: The State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, Wuxi 214122, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Zhou
authors.affiliation: The State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
authors.forename: Benxi
authors.initials: B
authors.lastname: Wei
authors.affiliation: The State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
authors.forename: Hongyan
authors.initials: H
authors.lastname: Li
authors.affiliation: The State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, Wuxi 214122, China.
authors.forename: Yaoqi
authors.initials: Y
authors.lastname: Tian
authors.affiliation: The State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
authors.forename: Barkat
authors.initials: B
authors.lastname: Ali
authors.affiliation: The State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, Wuxi 214122, China.
authors.forename: Xueming
authors.initials: X
authors.lastname: Xu
authors.affiliation: The State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, Wuxi 214122, China. Electronic address: jinlab2008@yahoo.com.
authors.forename: Zhengyu
authors.initials: Z
authors.lastname: Jin
mesh_terms: D016695:Glycosyltransferases / Q000737:chemistry*; D006868:Hydrolysis; D066298:In Vitro Techniques; D008970:Molecular Weight; D009844:Oligosaccharides / Q000737:chemistry; D012995:Solubility; D013213:Starch / Q000737:chemistry*; D003313:Zea mays / Q000737:chemistry*
chemical_list: D009844:Oligosaccharides; D013213:Starch; D016695:Glycosyltransferases
keywords: Digestibility; Maltotriohydrolase; Molecular characterization