High-resolution α-amylase assay combined with high-performance liquid chromatography−solid-phase extraction−nuclear magnetic resonance spectroscopy for expedited identification of α-amylase inhibitors – proof of concept and α-amylase inhibitor in cinnamon.

TY - JOUR

T1 - High-resolution α-amylase assay combined with high-performance liquid chromatography−solid-phase extraction−nuclear magnetic resonance spectroscopy for expedited identification of α-amylase inhibitors – proof of concept and α-amylase inhibitor in cinnamon.

AU - Okutan, Leyla

AU - Kongstad, Kenneth Thermann

AU - Jäger, Anna

AU - Stærk, Dan

PY - 2014/11/26

Y1 - 2014/11/26

N2 - Type 2 diabetes affects millions of people worldwide, and new improved drugs or functional foods containing selective α-amylase inhibitors are needed for improved management of blood glucose. In this article the development of a microplate-based high-resolution α-amylase inhibition assay with direct photometric measurement of α-amylase activity is described. The inhibition assay is based on porcine pancreatic α-amylase with 2-chloro-4-nitrophenyl-α-d-maltotriose as substrate, which this gives a stable, sensitive, and cheap inhibition assay as requested for high-resolution purposes. In combination with HPLC–HRMS–SPE–NMR, this provides an analytical platform that allows simultaneous chemical and biological profiling of α-amylase inhibitors in plant extracts. Proof-of-concept with an artificial mixture of six compounds—of which three are known α-amylase inhibitors—showed that the high-resolution α-amylase inhibition profiles allowed detection of sub-microgram amounts of the α-amylase inhibitors. Furthermore, the high-resolution α-amylase inhibition assay/HPLC–HRMS–SPE–NMR platform allowed identification of cinnamaldehyde as the α-amylase inhibitor in cinnamon (Cinnamomum verum Presl.).

AB - Type 2 diabetes affects millions of people worldwide, and new improved drugs or functional foods containing selective α-amylase inhibitors are needed for improved management of blood glucose. In this article the development of a microplate-based high-resolution α-amylase inhibition assay with direct photometric measurement of α-amylase activity is described. The inhibition assay is based on porcine pancreatic α-amylase with 2-chloro-4-nitrophenyl-α-d-maltotriose as substrate, which this gives a stable, sensitive, and cheap inhibition assay as requested for high-resolution purposes. In combination with HPLC–HRMS–SPE–NMR, this provides an analytical platform that allows simultaneous chemical and biological profiling of α-amylase inhibitors in plant extracts. Proof-of-concept with an artificial mixture of six compounds—of which three are known α-amylase inhibitors—showed that the high-resolution α-amylase inhibition profiles allowed detection of sub-microgram amounts of the α-amylase inhibitors. Furthermore, the high-resolution α-amylase inhibition assay/HPLC–HRMS–SPE–NMR platform allowed identification of cinnamaldehyde as the α-amylase inhibitor in cinnamon (Cinnamomum verum Presl.).

U2 - 10.1021/jf5047283

DO - 10.1021/jf5047283

M3 - Journal article

C2 - 25368916

SN - 0021-8561

VL - 62

SP - 11465

EP - 11471

JO - Journal of Agricultural and Food Chemistry

JF - Journal of Agricultural and Food Chemistry

IS - 47

ER -