title: Preparation of phosphorylated starch by dry-heating in the presence of pyrophosphate and its calcium-phosphate solubilizing ability.
abstract: Starch was phosphorylated through dry-heating in the presence of pyrophosphate at various conditions, and the characteristics of phosphorylated starch (PS) were examined. Starch phosphorylation increases as the pH increases from 3 to 6, but diminishes at pH 7. Increased temperatures enhance phosphorylation. Data from (31)P NMR suggests that starch phosphorylation occurs mainly at the C3-OH and C6-OH of the glucose residue. The phosphate linkage is mainly due to monostarch monophosphate. Although starch had almost no calcium phosphate-solubilising capacity, this capacity was markedly enhanced by phosphorylation. X-ray diffraction analysis indicates that the crystal structure of hydroxyapatite was not present in the calcium phosphate-PS complex.
authors.affiliation: School of Chemical Science and Technology, Yunnan University, Kunming, 650091 People's Republic China.
authors.forename: Rong
authors.initials: R
authors.lastname: Huang
authors.affiliation: School of Chemical Science and Technology, Yunnan University, Kunming, 650091 People's Republic China.
authors.forename: Can-Peng
authors.initials: CP
authors.lastname: Li
authors.affiliation: School of Chemical Science and Technology, Yunnan University, Kunming, 650091 People's Republic China.
authors.forename: Deyi
authors.initials: D
authors.lastname: Chen
authors.affiliation: School of Chemical Science and Technology, Yunnan University, Kunming, 650091 People's Republic China.
authors.forename: Gaihong
authors.initials: G
authors.lastname: Zhao
authors.affiliation: School of Chemical Science and Technology, Yunnan University, Kunming, 650091 People's Republic China.
authors.forename: Weihua
authors.initials: W
authors.lastname: Cheng
authors.affiliation: School of Chemical Science and Technology, Yunnan University, Kunming, 650091 People's Republic China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming, 650091 People's Republic China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhao
keywords: Calcium-phosphate solubilising capacity; Dry-heating; Phosphate linkage; Phosphorylation; Starch