The molecular organization of prenylated flavonoid xanthohumol in DPPC multibilayers: X-ray diffraction and FTIR spectroscopic studies

Abstract

Xanthohumol (XN) is the major prenylated flavonoid found in hop resin. It has attracted considerable attention in recent years due to its wide spectrum of biological activities and the beneficial effect on human health. Since lipid membrane is first target for biologically active compounds, we decided to investigate the influence of XN on the dipalmitoylphosphatidylcholine (DPPC) multibilayers. Interactions of XN with DPPC were investigated as a function of temperature and its concentration by using X-ray diffraction and the ATR-FTIR spectroscopy techniques. The aim of understanding the mechanisms of molecular interactions between XN and DPPC was to indicate the localization of the XN with respect to the membrane and the type of interaction with phospholipids. The results revealed that XN changes the physical properties of the DPPC multibilayers in the form of dry film. A new complex formation between XN and DPPC is reported. The detailed analysis of refraction effect indicates the changes in electron density ratio between hydrophobic and hydrophilic zones of lipid at phase transition. This is in compliance with reported changes in FTIR spectra where at pretransition XN moves from interface region between polar heads to the neighborhood of phosphate groups.

The influence of amphotericin B on the molecular organization and structural properties of DPPC lipid membranes modified by sterols

“…The second and third order diffraction peaks are observed only for low concentrations of AmB. A similar effect was observed in the case of 1,3,4-tiadiazole [32] and flavonoids [29]. The patterns obtained for higher AmB concentrations shows the same structures but with worse quality (weaker, more diffuse peaks) that the one obtained for 1 mol% of AmB.…”

“…The RH value was estimated based on the DPPC main lipid phase transition investigated by means of X-ray diffraction and HTR-FTIR, like in Ref. [29]. Because of the hyperbolic dependence between the main phase lipid transition and RH, the small differences in RH lead to $4°C deviation in it.…”

Effect of blending HA-g-PLLA on xanthohumol-loaded PLGA fiber membrane

“…The spectral band of ketone (C O) at 1626 cm −1 , a The letters "a-d" designated as blank PLGA, 10 wt% XN/PLGA, 10 wt% and 20 wt% XN/PLGA fiber membrane blended with 5 wt% HA-g-PLLA, respectively. C C vibrations in phenol and hydroxyl-benzoyl moieties at 1545 cm −1 and 1514 cm −1 , respectively, were also observed for pure XN [5] and the medicated fibers. For pure XN, the −OH vibration band was broad and centered at around 3400 cm −1 as a consequence of hydrogen bonds formation by XN intermolecular OH groups, but the absorbance of this band significantly decreased in XN/PLGA fibers.…”

“…It was first isolated by Power et al [2] and its molecular structure consists of two aromatic rings (A and B) substituted with hydroxyl and methoxyl groups, one ␣, ␤ unsaturated double bond, and the prenyl unit [3,4] (Scheme 1). XN has received growing attention in recent years due to its wide spectrum of biological activities and the beneficial effect on human health [5]. For example, XN regulates osteoblastic phenotypic gene expression in MCF-7 breast cancer cells [6], and XN at a concentration of 10-5 M has a strong inhibitory effect on bone resorption [7].…”

The chain order of binary unsaturated lipid bilayers modulated by aromatic-residue-containing peptides: an ATR-FTIR spectroscopy study

“…the structural changes in membranes induced via interactions with small molecules, 25,26 or antimicrobial cationic lipopeptides, 27 etc. Changes in the width and position of the lipid IR peaks can provide useful information regarding lipid membrane dynamics 28 and interactions of lipids with proteins.…”