Novel assay procedures for the measurement of α‐amylase in weather‐damaged wheat. (27th February 2015)

• Record Type: Journal Article
• Authors: Cornaggia, Claudio; Ivory, Ruth; Mangan, David; McCleary, Barry V
• Is Part Of: Journal of the science of food and agriculture. Volume 96:Number 2(2016)
• Page Start: 404
• Page End: 412
• Publication Date: 2015-02-27
• Subjects: α‐amylase -- preharvest sprouting -- weather‐damaged grains -- Amylase SD -- Falling Number; Food -- Periodicals; Agriculture -- Periodicals; 664
• DOI: 10.1002/jsfa.7103
• Languages: English
• ISSNs: 0022-5142

Abstract

Abstract: BACKGROUND: The measurement of α ‐amylase (EC 3.2.1.1) in sprout‐damaged grains is a crucial analysis yet a problematic one owing to the typically low α ‐amylase levels in ground wheat samples. A number of standardised methods such as the Falling Number method and the Ceralpha method exist which are routinely used for the assay of α ‐amylase. These methods, however, are either highly substrate‐dependent or lack the required sensitivity to assess sprout damage. RESULTS: Novel colorimetric and fluorometric reagents have been prepared (Amylase HR, Amylase SD, BzCNPG7 reagent and BzMUG7 reagent) for the direct and specific assay of α ‐amylase activity in sprout‐damaged wheat. Assays employing these reagents have been developed and optimised to include a decolourisation step using activated charcoal. When used in a convenient assay format, Amylase SD – containing EtNPG7 (II) as the colorimetric substrate and α ‐glucosidase as the ancillary enzyme – was found to be an excellent reagent for the assessment of sprout damage in wheat with incubation times as short as 5 min. CONCLUSION: The assay using Amylase SD is completely specific for α ‐amylase. The use of the Amylase SD assay represents a sensitive and valid alternative to the traditionally used Falling Number values for the assessment of sprout damage in wheat samples. © 2015 Society of Chemical Industry