title: Analysis of fatty acid content and composition in microalgae.
abstract: A method to determine the content and composition of total fatty acids present in microalgae is described. Fatty acids are a major constituent of microalgal biomass. These fatty acids can be present in different acyl-lipid classes. Especially the fatty acids present in triacylglycerol (TAG) are of commercial interest, because they can be used for production of transportation fuels, bulk chemicals, nutraceuticals (ω-3 fatty acids), and food commodities. To develop commercial applications, reliable analytical methods for quantification of fatty acid content and composition are needed. Microalgae are single cells surrounded by a rigid cell wall. A fatty acid analysis method should provide sufficient cell disruption to liberate all acyl lipids and the extraction procedure used should be able to extract all acyl lipid classes. With the method presented here all fatty acids present in microalgae can be accurately and reproducibly identified and quantified using small amounts of sample (5 mg) independent of their chain length, degree of unsaturation, or the lipid class they are part of. This method does not provide information about the relative abundance of different lipid classes, but can be extended to separate lipid classes from each other. The method is based on a sequence of mechanical cell disruption, solvent based lipid extraction, transesterification of fatty acids to fatty acid methyl esters (FAMEs), and quantification and identification of FAMEs using gas chromatography (GC-FID). A TAG internal standard (tripentadecanoin) is added prior to the analytical procedure to correct for losses during extraction and incomplete transesterification.
authors.affiliation: Bioprocess Engineering, Wageningen University and Research Center.
authors.forename: Guido
authors.initials: G
authors.lastname: Breuer
authors.forename: Wendy A C
authors.initials: WA
authors.lastname: Evers
authors.forename: Jeroen H
authors.initials: JH
authors.lastname: de Vree
authors.forename: Dorinde M M
authors.initials: DM
authors.lastname: Kleinegris
authors.forename: Dirk E
authors.initials: DE
authors.lastname: Martens
authors.forename: René H
authors.initials: RH
authors.lastname: Wijffels
authors.forename: Packo P
authors.initials: PP
authors.lastname: Lamers
mesh_terms: D002458:Cell Fractionation / Q000379:methods*; D002849:Chromatography, Gas / Q000379:methods*; D004951:Esterification; D005227:Fatty Acids / Q000032:analysis* / Q000378:metabolism; D059625:Liquid-Liquid Extraction / Q000379:methods*; D058086:Microalgae / Q000737:chemistry* / Q000378:metabolism
chemical_list: D005227:Fatty Acids