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Role of hydrogen bonds in ionic - liquid - mediated extraction of natural bioactive homologues / Kun Dong in Industrial & engineering chemistry research, Vol. 51 N° 14 (Avril 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 14 (Avril 2012) . - pp. 5299–5308 Titre : Role of hydrogen bonds in ionic - liquid - mediated extraction of natural bioactive homologues Type de document : texte imprimé Auteurs : Kun Dong, Auteur ; Yifeng Cao, Auteur ; Qiwei Yang, Auteur Année de publication : 2012 Article en page(s) : pp. 5299–5308 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Hydrogen  Ionic  liquid Résumé : The technologies of ionic-liquid-mediated extraction have shown the good prospects for replacing traditional methods for separating natural bioactive homologues. However, so far, the roles and interactions of the anions and cations in the extraction process are not clear, which seriously hinders the further exploration of this new extraction technology. In this work, we report a detailed computational study, combined with experiment, on the interactions and hydrogen bonds between 1-butyl-3-methylimidazlium hexafluorophosphate ([Bmim][PF6]) ionic liquid (IL) and natural bioactive homologues, namely, three soybean isoflavone aglycones as model compounds. The distribution coefficients, D, of the three aglycones were experimentally determined in the [Bmim][PF6]–water biphasic system, and the order was found to be genistein (182.6) > daidzein (51.4) > glycitein (41.9). In DFT calculations, the lowest-energy complexes were obtained, and it was found that H-bonds are explicit intermolecular interactions in these complexes and that the IL can recognize these similar homologues by forming different H-bonds with the phenolic hydroxyls of aglycones. Furthermore, we found that the anions play a more important role in recognition than the cations. Subsequently, results of molecular dynamics (MD) simulations exhibited a good match with the structures of the isolated complexes calculated by DFT and also discovered that H-bonds were the main interactions between the anions and the phenolic hydroxyls in the first solvation shell. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie203044m [article] Role of hydrogen bonds in ionic - liquid - mediated extraction of natural bioactive homologues [texte imprimé] / Kun Dong, Auteur ; Yifeng Cao, Auteur ; Qiwei Yang, Auteur . - 2012 . - pp. 5299–5308. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 14 (Avril 2012) . - pp. 5299–5308 Mots-clés : Hydrogen  Ionic  liquid Résumé : The technologies of ionic-liquid-mediated extraction have shown the good prospects for replacing traditional methods for separating natural bioactive homologues. However, so far, the roles and interactions of the anions and cations in the extraction process are not clear, which seriously hinders the further exploration of this new extraction technology. In this work, we report a detailed computational study, combined with experiment, on the interactions and hydrogen bonds between 1-butyl-3-methylimidazlium hexafluorophosphate ([Bmim][PF6]) ionic liquid (IL) and natural bioactive homologues, namely, three soybean isoflavone aglycones as model compounds. The distribution coefficients, D, of the three aglycones were experimentally determined in the [Bmim][PF6]–water biphasic system, and the order was found to be genistein (182.6) > daidzein (51.4) > glycitein (41.9). In DFT calculations, the lowest-energy complexes were obtained, and it was found that H-bonds are explicit intermolecular interactions in these complexes and that the IL can recognize these similar homologues by forming different H-bonds with the phenolic hydroxyls of aglycones. Furthermore, we found that the anions play a more important role in recognition than the cations. Subsequently, results of molecular dynamics (MD) simulations exhibited a good match with the structures of the isolated complexes calculated by DFT and also discovered that H-bonds were the main interactions between the anions and the phenolic hydroxyls in the first solvation shell. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie203044m

Selective separation of tocopherol homologues by liquid-liquid extraction using ionic liquids / Qiwei Yang in Industrial & engineering chemistry research, Vol. 48 N° 13 (Juillet 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 13 (Juillet 2009) . - pp. 6417–6422 Titre : Selective separation of tocopherol homologues by liquid-liquid extraction using ionic liquids Type de document : texte imprimé Auteurs : Qiwei Yang, Auteur ; Huabin Xing, Auteur ; Yifeng Cao, Auteur Année de publication : 2009 Article en page(s) : pp. 6417–6422 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Pocopherol  homologues  Liquid-liquid  extraction  Ionic  liquid Résumé : Selective separation of tocopherol homologues was performed by liquid−liquid extraction, using ionic liquids (ILs) as extractants in the presence of diluent. The distribution coefficients and selectivities of tocopherols in the biphasic system were determined. A selectivity of δ-tocopherol to α-tocopherol up to 21.3 was achieved when using [bmim]Cl as extractant diluted by methanol. Considering the structural differences of tocopherols, the separation mechanism based on the hydrogen-bonding interaction between IL’s anion and the −OH group on the tocopherols was proposed. The separation efficiency of IL was greatly affected by its anion, and followed the order [bmim]BF4 < [bmim]CF3SO3 < [bmim]Cl under the same conditions, which is consistent with the ascending order of IL’s hydrogen-bond basicity strengths. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801847e [article] Selective separation of tocopherol homologues by liquid-liquid extraction using ionic liquids [texte imprimé] / Qiwei Yang, Auteur ; Huabin Xing, Auteur ; Yifeng Cao, Auteur . - 2009 . - pp. 6417–6422. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 13 (Juillet 2009) . - pp. 6417–6422 Mots-clés : Pocopherol  homologues  Liquid-liquid  extraction  Ionic  liquid Résumé : Selective separation of tocopherol homologues was performed by liquid−liquid extraction, using ionic liquids (ILs) as extractants in the presence of diluent. The distribution coefficients and selectivities of tocopherols in the biphasic system were determined. A selectivity of δ-tocopherol to α-tocopherol up to 21.3 was achieved when using [bmim]Cl as extractant diluted by methanol. Considering the structural differences of tocopherols, the separation mechanism based on the hydrogen-bonding interaction between IL’s anion and the −OH group on the tocopherols was proposed. The separation efficiency of IL was greatly affected by its anion, and followed the order [bmim]BF4 < [bmim]CF3SO3 < [bmim]Cl under the same conditions, which is consistent with the ascending order of IL’s hydrogen-bond basicity strengths. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801847e