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Kfoury M.,Lebanese University | Auezova L.,Lebanese University | Greige-Gerges H.,Lebanese University | Fourmentin S.,Unite de Chimie Environnementale et Interactions sur le Vivant UCEIV
Carbohydrate Polymers | Year: 2015

Abstract Essential oils (EOs) are gaining great interest as alternatives for harmful synthetic food preservatives. Due to their volatile nature, they could be applied in food packaging to improve food quality and extend shelf-life. To provide long-term effects of EOs by increasing their retention and ensuring controlled release of their components, they could be encapsulated in cyclodextrins (CDs). Herein, the ability of six CDs to retain nine EOs and to bind their individual components was investigated. Retention capacities and binding abilities of CDs were assessed by static headspace-gas chromatography (SH-GC) using a new validated "rapid method". The ability of CDs to generate controlled release systems was examined by multiple headspace extraction (MHE). Finally, radical scavenging activity of free and encapsulated EOs was evaluated. The highest retention capacity toward the studied EOs was obtained for β-CD and its derivatives (69-78%). Also, β-CD and its derivatives showed, with one exception, the highest Kf values for all the studied guests. In addition, encapsulation in CDs reduced the releasing rate of EO components (from 1.43 to 2.43-fold for β-CD/Satureja montana EO used as a model). Furthermore, the inclusion complexes showed higher ABTS+ scavenging capacity than the free EOs. Results confirmed the usefulness of CDs as encapsulant for EOs and should encourage their application in food and as part of active packaging systems. © 2015 Elsevier Ltd. Source


Gharib R.,Lebanese University | Greige-Gerges H.,Lebanese University | Fourmentin S.,Unite de Chimie Environnementale et Interactions sur le Vivant UCEIV | Charcosset C.,University of Lyon | Auezova L.,Lebanese University
Carbohydrate Polymers | Year: 2015

Cyclodextrins (CDs) are cyclic oligosaccharides, consisting of glucopyranose units, which are able to form host-guest inclusion complexes with lipophilic molecules. The ability of CD to increase drug solubility may be used to increase drug entrapment in the aqueous compartment of liposomes and liposomes can protect CD/drug inclusion complexes until drug release. Liposomes are phospholipid vesicles composed of lipid bilayers enclosing one or more aqueous compartments. They have been widely used as safe and effective carriers for both hydrophilic and lipophilic drugs. However, lipophilic drugs incorporated in the membrane bilayers can be rapidly released, which limits the effectiveness of this drug delivery system. The coupling of both delivery systems by encapsulating CD/drug inclusion complex into liposomes is proposed to circumvent the drawbacks of each separate system. Here, we review the literature regarding the encapsulation of CD/drug inclusion complex into conventional, deformable and double loaded liposomes. The review highlights the characteristics of these systems and presents the advantages and disadvantages of each one. © 2015 Elsevier Ltd. All rights reserved. Source


Kfoury M.,Unite de Chimie Environnementale et Interactions sur le Vivant UCEIV | Kfoury M.,Lebanese University | Balan R.,University of Bacau | Landy D.,Unite de Chimie Environnementale et Interactions sur le Vivant UCEIV | And 2 more authors.
Supramolecular Chemistry | Year: 2015

The formation of inclusion complexes of six essential oil (EO) components (β-caryophyllene, cis-ocimene, trans-ocimene, sabinene hydrate (thujanol), γ-terpinene and α-terpineol) with six cyclodextrins (CDs) (α-CD, β-CD, γ-CD, HP-β-CD, RAMEB and CRYSMEB) was investigated by using static headspace-gas chromatography and UV-visible spectroscopy. Retention studies showed that CDs could efficiently reduce the volatility of EO components except for β-caryophyllene with α-CD. In this case, no inclusion complex was detected while for other compounds the formation of 1:1 inclusion complexes was observed. Results revealed that the inclusion stability mainly depends on geometric complementarity between encapsulated molecule and CD's cavity. Molecular modelling was used to investigate the complementarities between host and guest. Thus, CDs could efficiently be regarded as promising encapsulants for EO components leading to improve their application in cosmetic, pharmaceutical and agriculture fields. © 2015 © 2015 Taylor & Francis. Source


Thiare D.D.,Cheikh Anta Diop University | Khonte A.,Cheikh Anta Diop University | Diop A.,Unite de Chimie Environnementale et Interactions sur le Vivant UCEIV | Diop A.,Cheikh Anta Diop University | And 4 more authors.
Journal of Molecular Liquids | Year: 2015

Abstract Solvatochromic behavior of 2-aminobenzimidazole (2-AB) has been studied in different solvents at room temperature. The observation of the bathochromic shift in the absorption and fluorescence spectra of molecules indicates a strong interaction with solvents in the excited state. The difference in the excited-state (μe) and the ground-state (μg) dipole moments has been estimated by using the theory of solvatochromism from Bakhshiev, Bilot-Kawski, and Dimroth-Reichardt equations. Higher values of dipole moment have been observed for excited state compared to the corresponding ground state values indicating an intramolecular charge-transfer (ICT). Then in order to carry out a theoretical investigation, the values of dipole moments were calculated in the gas phase with TDDFT/B3LYP. Based on these results, we propose a solvation model consistent with theoretical and experimental results wherein we showed the specific interactions between solvent molecules and aminobenzimidazole at the excited state. © 2015 Elsevier B.V. Source


Kfoury M.,Lebanese University | Auezova L.,Lebanese University | Ruellan S.,Unite de Chimie Environnementale et Interactions sur le Vivant UCEIV | Greige-Gerges H.,Lebanese University | Fourmentin S.,Unite de Chimie Environnementale et Interactions sur le Vivant UCEIV
Carbohydrate Polymers | Year: 2015

Inclusion complexes of estragole (ES) as pure compound and as main component of basil and tarragon essential oils (EOs) with α-cyclodextrin (α-CD), β-cyclodextrin (β-CD), hydroxypropyl-β-cyclodextrin (HP-β-CD), randomly methylated-β-cyclodextrin (RAMEB), a low methylated-β-cyclodextrin (CRYSMEB) and γ-cyclodextrin (γ-CD) were characterized. Formation constants (Kf) of the complexes were determined in aqueous solution by nonlinear regression analysis using static headspace gas chromatography (SH-GC) and UV-visible spectroscopy. Solid inclusion complexes were prepared by the freeze-drying method for different CD:ES molar ratios and were characterized by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR). Inclusion complexes formation allowed the controlled release of ES. Moreover, increased DPPH radical scavenging activity and photostability of ES and ES containing EOs (ESEOs) were observed in the presence of CDs. These findings suggest that encapsulation with CDs could be an efficient tool to improve the use of ES and ESEOs in aromatherapy, cosmetic and food fields. © 2014 Elsevier Ltd. Source

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