title: "Bligh and Dyer" and Folch Methods for Solid-Liquid-Liquid Extraction of Lipids from Microorganisms. Comprehension of Solvatation Mechanisms and towards Substitution with Alternative Solvents.
abstract: Bligh and Dyer (B &amp; D) or Folch procedures for the extraction and separation of lipids from microorganisms and biological tissues using chloroform/methanol/water have been used tens of thousands of times and are "gold standards" for the analysis of extracted lipids. Based on the Conductor-like Screening MOdel for realistic Solvatation (COSMO-RS), we select ethanol and ethyl acetate as being potentially suitable for the substitution of methanol and chloroform. We confirm this by performing solid-liquid extraction of yeast (Yarrowia lipolytica IFP29) and subsequent liquid-liquid partition-the two steps of routine extraction. For this purpose, we consider similar points in the ternary phase diagrams of water/methanol/chloroform and water/ethanol/ethyl acetate, both in the monophasic mixtures and in the liquid-liquid miscibility gap. Based on high performance thin-layer chromatography (HPTLC) to obtain the distribution of lipids classes, and gas chromatography coupled with a flame ionisation detector (GC/FID) to obtain fatty acid profiles, this greener solvents pair is found to be almost as effective as the classic methanol-chloroform couple in terms of efficiency and selectivity of lipids and non-lipid material. Moreover, using these bio-sourced solvents as an alternative system is shown to be as effective as the classical system in terms of the yield of lipids extracted from microorganism tissues, independently of their apparent hydrophilicity.
authors.affiliation: GREEN (Groupe de Recherche en Eco-Extraction de Produits Naturels), Université d'Avignon et des Pays du Vaucluse, INRA, UMR 408, GREEN, F-84000 Avignon, France. cassndra.breil@alumni.univ-avignon.fr.
authors.forename: Cassandra
authors.initials: C
authors.lastname: Breil
authors.affiliation: GREEN (Groupe de Recherche en Eco-Extraction de Produits Naturels), Université d'Avignon et des Pays du Vaucluse, INRA, UMR 408, GREEN, F-84000 Avignon, France. maryline.vian@univ-avignon.fr.
authors.forename: Maryline
authors.initials: M
authors.lastname: Abert Vian
authors.affiliation: Institut de Chimie Séparative de Marcoule, F-30207 Bagnols Sur Cèze, France. thomas.zemb@icsm.fr.
authors.forename: Thomas
authors.initials: T
authors.lastname: Zemb
authors.affiliation: Institute of Physical and Theoretical Chemistry, University of Regensburg, D-93040 Regensburg, Germany. werner.kunz@chemie.uni-regensburg.de.
authors.forename: Werner
authors.initials: W
authors.lastname: Kunz
authors.affiliation: GREEN (Groupe de Recherche en Eco-Extraction de Produits Naturels), Université d'Avignon et des Pays du Vaucluse, INRA, UMR 408, GREEN, F-84000 Avignon, France. farid.chemat@univ-avignon.fr.
authors.forename: Farid
authors.initials: F
authors.lastname: Chemat
mesh_terms: D002725:Chloroform / Q000737:chemistry; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D000431:Ethanol / Q000737:chemistry; D008055:Lipids / Q000032:analysis / Q000737:chemistry*; D059625:Liquid-Liquid Extraction; D000432:Methanol / Q000737:chemistry; D052616:Solid Phase Extraction; D012997:Solvents / Q000737:chemistry*; D014867:Water / Q000737:chemistry; D025062:Yarrowia / Q000378:metabolism*
chemical_list: D008055:Lipids; D012997:Solvents; D014867:Water; D000431:Ethanol; D002725:Chloroform; D000432:Methanol
keywords: Bligh and Dyer; Folch; bio-sourced solvent; lipids; yeast