TY - JOUR

T1 - Combined use of high-resolution α-glucosidase inhibition profiling and HPLC-HRMS-SPE-NMR for investigation of antidiabetic principles in crude plant extracts

AU - Kongstad, Kenneth Thermann

AU - Özdemir, Ceylan

AU - Barzak, Asmah

AU - Wubshet, Sileshi Gizachew

AU - Stærk, Dan

PY - 2015/2/5

Y1 - 2015/2/5

N2 - Type 2 diabetes is a metabolic disorder affecting millions of people worldwide, and new drug leads or functional foods containing selective α-glucosidase inhibitors are needed. Crude extract of 24 plants were assessed for α-glucosidase inhibitory activity. Methanol extracts of Cinnamomum zeylanicum bark, Rheum rhabarbarum peel, and Rheum palmatum root and ethyl acetate extracts of C. zeylanicum bark, Allium ascalonicum peel, and R. palmatum root showed IC50 values below 20 μg/mL. Subsequently, high-resolution α-glucosidase profiling was used in combination with high-performance liquid chromatography–high-resolution mass spectrometry–solid-phase extraction–nuclear magnetic resonance spectroscopy for identification of metabolites responsible for the α-glucosidase inhibitory activity. Quercetin (1) and its dimer (2), trimer (3), and tetramer (4) were identified as main α-glucosidase inhibitors in A. ascalonicum peel, whereas (E)-piceatannol 3′-O-β-d-glucopyranoside (5), (E)-rhapontigenin 3′-O-β-d-glucopyranoside (6), (E)-piceatannol (8), and emodin (12) were identified as main α-glucosidase inhibitors in R. palmatum root.

AB - Type 2 diabetes is a metabolic disorder affecting millions of people worldwide, and new drug leads or functional foods containing selective α-glucosidase inhibitors are needed. Crude extract of 24 plants were assessed for α-glucosidase inhibitory activity. Methanol extracts of Cinnamomum zeylanicum bark, Rheum rhabarbarum peel, and Rheum palmatum root and ethyl acetate extracts of C. zeylanicum bark, Allium ascalonicum peel, and R. palmatum root showed IC50 values below 20 μg/mL. Subsequently, high-resolution α-glucosidase profiling was used in combination with high-performance liquid chromatography–high-resolution mass spectrometry–solid-phase extraction–nuclear magnetic resonance spectroscopy for identification of metabolites responsible for the α-glucosidase inhibitory activity. Quercetin (1) and its dimer (2), trimer (3), and tetramer (4) were identified as main α-glucosidase inhibitors in A. ascalonicum peel, whereas (E)-piceatannol 3′-O-β-d-glucopyranoside (5), (E)-rhapontigenin 3′-O-β-d-glucopyranoside (6), (E)-piceatannol (8), and emodin (12) were identified as main α-glucosidase inhibitors in R. palmatum root.

U2 - 10.1021/jf506297k

DO - 10.1021/jf506297k

M3 - Journal article

C2 - 25652946

VL - 63

SP - 2257

EP - 2263

JO - Journal of Agricultural and Food Chemistry

JF - Journal of Agricultural and Food Chemistry

SN - 0021-8561

IS - 8

ER -