Investigation of heptakis(2,6‐di‐O‐methyl)‐β‐cyclodextrin inclusion complexes with flavonoid glycosides by electrospray ionization mass spectrometry

Abstract

The non-covalent complexes between three flavonoid glycosides (quercitrin, hyperoside and rutin) and heptakis(2,6-di-O-methyl)-beta-cyclodextrin (DM-beta-CD) were investigated by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS). The 1:1 complexation of each flavonoid glycoside (guest) to the DM-beta-CD (host) was monitored in the negative ion mode by mixing each guest with an up to 30-fold molar excess of the host. The binding constants for all complexes were calculated by a linear equation in the order: DM-beta-CD:quercitrin > DM-beta-CD:rutin > DM-beta-CD:hyperoside. A binding model for the complexes has also been proposed based on the binding constants and tandem mass spectrometric data of these complexes.

Phosphatidylethanolamine of Helicobacter pylori Functions as a Steroid-Binding Lipid in the Assimilation of Free Cholesterol and 3 -Hydroxl Steroids into the Bacterial Cell Membrane

“…dM␤CD forms an inclusion complex with various hydrophobic compounds and solubilizes the compounds into water solvent. Hydrophobic compounds, such as flavonoid glycosides (31) and sodium salicylate (12), are thought to bind to the inner ring structure of the dM␤CD molecule at a molar ratio of 1:1 via molecular interactions, such as hydrophobic bonding, hydrogen bonding, and van der Waals attraction. Though FC has been identified as one of the most suitable "guest molecules" of dM␤CD in forming the inclusion complex (3,6,18,30,32), the molecular interaction between FC and dM␤CD has yet to be understood in detail.…”

Detoxification of 7-Dehydrocholesterol Fatal to Helicobacter pylori Is a Novel Role of Cholesterol Glucosylation

“…dM␤CD is an annular structure formed by seven dimethylated D-glucose molecules, embeds various hydrophobic compounds inside its molecule, and solubilizes hydrophobic compounds in a water solvent (28,29). In particular, FC is one of the most suitable "guest molecules" of dM␤CD for forming an inclusion complex (30)(31)(32)(33)(34).…”

Characterization of cyclodextrin complexes of camostat mesylate by ESI mass spectrometry and NMR spectroscopy

“…A relative intensity I r , defined as I r = I c /(I c + I f ) in which I f and I c are defined as the abundances of free 1 and the complex with CD, respectively, was used to determine the effect of the concentrations of the CDs on relative abundance of the complexes. As reported previously [16][17][18], I r is connected with K st by the following equation:…”