Magnetic Ligand Fishing as a Targeting Tool for HPLC-HRMS-SPE-NMR: α-Glucosidase Inhibitory Ligands and Alkylresorcinol Glycosides from Eugenia catharinae.
A bioanalytical platform combining magnetic ligand fishing for α-glucosidase inhibition profiling and HPLC-HRMS-SPE-NMR for structural identification of α-glucosidase inhibitory ligands, both directly from crude plant extracts, is presented. Magnetic beads with N-terminus-coupled α-glucosidase were synthesized and characterized for their inherent catalytic activity. Ligand fishing with the immobilized enzyme was optimized using an artificial test mixture consisting of caffeine, ferulic acid, and luteolin before proof-of-concept with the crude extract of Eugenia catharinae. The combination of ligand fishing and HPLC-HRMS-SPE-NMR identified myricetin 3-O-α-L-rhamnopyranoside, myricetin, quercetin, and kaempferol as α-glucosidase inhibitory ligands in E. catharinae. Furthermore, HPLC-HRMS-SPE-NMR analysis led to identification of six new alkylresorcinol glycosides, i.e., 5-(2-oxopentyl)resorcinol 4-O-β-D-glucopyranoside, 5-propylresorcinol 4-O-β-D-glucopyranoside, 5-pentylresorcinol 4-O-[α-D-apiofuranosyl-(1→6)]-β-D-glucopyranoside, 5-pentylresorcinol 4-O-β-D-glucopyranoside, 4-hydroxy-3-O-methyl-5-pentylresorcinol 1-O-β-D-glucopyranoside, and 3-O-methyl-5-pentylresorcinol 1-O-[β-D-glucopyranosyl-(1→6)]-β-D-glucopyranoside.
Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen , Universitetsparken 2, DK-2100 Copenhagen, Denmark.
Sileshi G
SG
Wubshet
Laboratório de Química de Produtos Naturais, Departamento de Química, Universidade Federal de Santa Catarina, Campus Trindade , Florianópolis-SC, 88040-900, Brazil.
Inês M C
IM
Brighente
Biomedical Research Center, National Institute on Aging, National Institutes of Health , 251 Bayview Boulevard, Baltimore, Maryland 21224, United States.
Ruin
R
Moaddel
Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen , Universitetsparken 2, DK-2100 Copenhagen, Denmark.
Dan
D
Staerk
D001938:Brazil; D002851:Chromatography, High Pressure Liquid; D000068856:Eugenia / Q000737:chemistry*; D065089:Glycoside Hydrolase Inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D008024:Ligands; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D018515:Plant Leaves / Q000737:chemistry; D012118:Resorcinols / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D000520:alpha-Glucosidases / Q000187:drug effects*
D065089:Glycoside Hydrolase Inhibitors; D006027:Glycosides; D008024:Ligands; D012118:Resorcinols; D000520:alpha-Glucosidases