Competitive and product inhibition-based α-amylase activity analysis method

• Published in: Clinical biochemistry 2008-03, Vol.41 (4), p.325-330
• Main Authors: Yamaguchi, Masaki, Wakasugi, Junichi, Sakakima, Josaku
• Format: Article
• Language: English
• Subjects: alpha-Amylases - chemistry; alpha-Amylases - metabolism; Chemistry, Clinical - instrumentation; Chemistry, Clinical - methods; Competitive inhibition; Enzyme Activation; Enzyme activity; Gal-G2-CNP; Models, Biological; Oligosaccharides - chemistry; Oligosaccharides - metabolism; Product inhibition; Protein Binding; Trisaccharides - metabolism; α-amylase
• ISSN: 0009-9120; 1873-2933
• DOI: 10.1016/j.clinbiochem.2007.10.016

To propose a methodology for analyzing salivary α-amylase activity (sAMY) for a hand-held device that can be used easily and quickly for evaluating human psychological effects. An improved method for the analysis of sAMY is proposed using competitive and product inhibition in a dry-chemistry system with a reagent paper containing 2-chloro-4-nitrophenyl-4- O-β- d-galactopyranosylmaltoside. Not only the competitive (maltopentaose) inhibitor, but also the product (maltotriose) inhibitor significantly reduce the reaction speed of sAMY. There is an independent effect between the two inhibitors. The dynamic linear range of the analysis can be enhanced by 2.5 times larger by adding the competitive and product inhibitors simultaneously and by preparing their concentrations appropriately. It is considered that the application of competitive and product inhibition can be effective from the viewpoint of enhancing analysis range and effectively reducing costs.