Abstract
Pancreatic α-amylase plays an important role in dietary starch hydrolysis in the small intestine and participates in enhanced glucose concentration after meals. It seems to be a problem for diabetic patients, who suffer from longer postprandial hyperglycemia after meal consumption than healthy people. There are commercially available drugs that inhibit α-amylase and thus reduce the postprandial hyperglycemia effect. However, these drugs may cause severe side effects. Conversely, some naturally occurring flavonoids were suggested to have an α-amylase-inhibiting effect without any side effects. There had been no rapid, undemanding method in terms of sample and reagent preparation that would enable screening of many potential inhibitors. Therefore, we developed an online capillary electrophoresis method to monitor α-amylase activity in the presence of an inhibitor. Each reaction constituent was introduced separately, directly into a capillary where the reagents were mixed by diffusion, which resulted in a 5-min analysis including conditioning of the capillary. We applied the method to test the inhibitory effect of flavonoid standards and their mixture and we investigated the inhibitory effect of ethanolic extract from Betula pendula bark. The developed method presents a faster and less expensive alternative to previously described offline methods.
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Acknowledgements
We thank to Assoc. Prof. Václav Richtr (Department of Chemistry, University of West Bohemia) for the Betula pendula extract.
Funding
This study was financially supported by the Charles University (SVV grant no. 260440) and Charles University Research Centre program No. UNCE/SCI/014. This study does not contain any studies with human participants or animals performed by any of the authors.
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Hodek, O., Křížek, T., Coufal, P. et al. Online screening of α-amylase inhibitors by capillary electrophoresis. Anal Bioanal Chem 410, 4213–4218 (2018). https://doi.org/10.1007/s00216-018-1073-z
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DOI: https://doi.org/10.1007/s00216-018-1073-z