A New Microtiter Plate-based Screening Method for Microorganisms Producing Alpha-amylase Inhibitors

摘要

Alpha-amylase inhibitors are widely used by the pharmaceutical and agricultural industries, such as the treatment of diabetes and obesity and insect controller. Here, we developed a colorimetric method to screen for α-amylase inhibitor producing strains or mutants with higher α-amylase inhibitor productivity. This method relies on absorbance changes at 402 run that are due to the inhibition of a-amylase catalyzed hydrolysis of 2-Chloro-4-nitro-phenyl-4-O-β-D-galactopyranosyl-maltoside by α-amylase inhibitors. The assay can be performed on a microtiter plate, making it simple and convenient. Using this method, α-amylase inhibitor producing strains and mutants with higher a-amylase inhibitor productivity can be rapidly screened. One strain, ZJB-08196, with the highest α-amylase inhibition was isolated and identified as Actino-planes utahensis, and one mutant with higher acarbose production was obtained by screening 3,000 variants using this method.