Binding interactions of alpha-amylase with starch granules: The influence of supramolecular structure and surface area

Research output: Contribution to journalArticlepeer-review

113 Citations (Scopus)

Abstract

Factors affecting the a-amylase-catalysed hydrolysis kinetics of starch are incompletely understood, but are of importance to postprandial metabolism and many industrial processes (e.g. bioethanol production). Also, reports on the role of surface area and amorphous content in influencing amylolysis are conflicting. Binding kinetics of pancreatic alpha-amylase with native starch granules at 0 degrees C were compared with information on starch characteristics. Dissociation constants (K-d), obtained for amylase binding to starches of different particle sizes by solution-depletion assay, varied from 0.16 to 2.05 mg/mL. K-d was strongly dependent on specific surface area of the starch granules. Binding rates of amylase (4 nM concentration) to the starch were calculated from the time-dependency of amylase depletion and ranged from 1.95 to 22.04 x 10(-3) s(-1). The rates were strongly dependent on the degree of order of alpha-glucan chains of starch, as measured by DSC and FFIR-ATR. Thus, alpha-amylase binds most readily to exposed/available amorphous alpha-glucan chains. (C) 2011 Elsevier Ltd. All rights reserved.
Original languageEnglish
Pages (from-to)1038-1047
Number of pages10
JournalCARBOHYDRATE POLYMERS
Volume86
Issue number2
DOIs
Publication statusPublished - 15 Aug 2011

Fingerprint

Dive into the research topics of 'Binding interactions of alpha-amylase with starch granules: The influence of supramolecular structure and surface area'. Together they form a unique fingerprint.

Cite this