title: Impact of amylosucrase modification on the structural and physicochemical properties of native and acid-thinned waxy corn starch.
abstract: Recombinant amylosucrase from Neisseria polysaccharea was utilized to modify native and acid-thinned starches. The molecular structures and physicochemical properties of modified starches were investigated. Acid-thinned starch displayed much lower viscosity after gelatinization than did the native starch. However, the enzyme exhibited similar catalytic efficiency for both forms of starch. The modified starches had higher proportions of long (DP>33) and intermediate chains (DP 13-33), and X-ray diffraction showed a B-type crystalline structure for all modified starches. With increasing reaction time, the relative crystallinity and endothermic enthalpy of the modified starches gradually decreased, whereas the melting peak temperatures and resistant starch contents increased. Slight differences were observed in thermal parameters, relative crystallinity, and branch chain length distribution between the modified native and acid-thinned starches. Moreover, the digestibility of the modified starches was not affected by acid hydrolysis pretreatment, but was affected by the percentage of intermediate and long chains.
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China; National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, People's Republic of China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China.
authors.forename: Hao
authors.initials: H
authors.lastname: Zhang
authors.affiliation: School of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China.
authors.forename: Xing
authors.initials: X
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China; National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, People's Republic of China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China.
authors.forename: Jian
authors.initials: J
authors.lastname: He
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China; National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, People's Republic of China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China.
authors.forename: Tao
authors.initials: T
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China; National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, People's Republic of China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China.
authors.forename: Xiaohu
authors.initials: X
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China; National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, People's Republic of China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China.
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China; National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, People's Republic of China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China. Electronic address: nedved_wr@jiangnan.edu.cn.
authors.forename: Ren
authors.initials: R
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China; National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, People's Republic of China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, People's Republic of China. Electronic address: zxchen_2008@126.com.
authors.forename: Zhengxing
authors.initials: Z
authors.lastname: Chen
mesh_terms: D000687:Amylopectin / Q000737:chemistry*; D005964:Glucosyltransferases / Q000737:chemistry*; D006868:Hydrolysis; D015394:Molecular Structure; D009343:Neisseria / Q000201:enzymology*; D013213:Starch / Q000737:chemistry*; D013696:Temperature; D013816:Thermodynamics; D014783:Viscosity; D014961:X-Ray Diffraction; D003313:Zea mays / Q000737:chemistry*
chemical_list: D013213:Starch; D000687:Amylopectin; D005964:Glucosyltransferases; C019700:amylosucrase
keywords: Amylosucrase; Enzymatic elongation; Resistant starch; Waxy corn starch