Influence of Eugenol on the Organization and Dynamics of Lipid Membranes: A Phase-Dependent Study

Abstract

Eugenol is known for its antimicrobial effects against microorganisms responsible for infectious diseases in humans, food-borne pathogens, and oral pathogens. In spite of several reports on the antimicrobial function of eugenol by modulating the structural properties of cell membranes, there is limited information on the influence of eugenol in the lipid membrane. In this work, we explored the effect of eugenol on the organization and dynamics of large unilamellar vesicles (LUVs) of DMPC using the intrinsic fluorescence of eugenol and an extrinsic hydrophobic probe, DPH, in varying phases. The organization and dynamics of the bilayers of DMPC vesicles were monitored by utilizing varieties of steady-state and time-resolved fluorescence measurements. Our results show that eugenol stabilizes the gel phase and elevates the phase-transition temperature of DMPC in a concentration-dependent fashion. Fluorescence lifetime measurements demonstrate that higher eugenol-induced water penetration was observed in fluid-phase membranes. Time-resolved anisotropy measurements demonstrate that eugenol reduces the semiangle of DPH wobbling-in-a-cone in gel-phase membranes, whereas the semiangle remains unaffected in fluid-phase membrane. This implies that the eugenol further orders the gel-phase membrane, and this could be a plausible reason for the eugenol-dependent elevation of the phase-transition temperature of DMPC. We envisage that these results will contribute important information to understand the interaction of eugenol with biological membranes.

Fusogenic Effect of Cholesterol Prevails over the Inhibitory Effect of a Peptide-Based Membrane Fusion Inhibitor

“…The amount of DMSO was always less than 1% (v/v), and this amount of DMSO had no detectable effect on either fusion or membrane structure. 44 Preparation of Vesicles. Vesicles of hydrodynamic radii 40−50 nm with a polydispersity index less than 0.2 were prepared from either a mixture of DOPC/DOPE/DOPG (60/30/10 mol %), DOPC/ DOPE/DOPG/CH (50/30/10/10), or DOPC/DOPE/DOPG/CH (40/30/10/20 mol %), using the sonication method.…”

“…The DMSO content was always less than 1% (v/v), and it has been found that this small quantity of DMSO had no detectable effect on the membrane structure and peptide interaction with the membrane. 44 Steady-State Fluorescence Measurements. Steady-state fluorescence measurements were carried out at 37 °C with a Hitachi F-7000 (Japan) spectrofluorometer using a 1 cm × 1 cm quartz cuvette.…”

“…Peptide stock solutions were prepared in DMSO, and small aliquots of these solutions were added to vesicle suspensions. The amount of DMSO was always less than 1% (v/v), and this amount of DMSO had no detectable effect on either fusion or membrane structure …”

“…Small aliquots of stock solutions were added to the working solutions. The DMSO content was always less than 1% (v/v), and it has been found that this small quantity of DMSO had no detectable effect on the membrane structure and peptide interaction with the membrane …”

Assessment of the electrochemical behaviour of Nickel-Titanium-based orthodontic wires: Effect of some natural corrosion inhibitors in comparison with fluoride

“…In order to understand our finding, a literature research about the composition of clove essential oil was carried out. Eugenol is actually the major constituent of clove essential oil, it is a hydroxyphenyl propene that demonstrated a great biological activity with an antimicrobial action on oral pathogens (27,28). These results suggest that Eugenol could be used in toothpastes and mouthwashes especially for patients with fixed orthodontic appliances instead of Sodium Fluoride.…”