title: Qualitative analysis of algal secretions with multiple mass spectrometric platforms.
abstract: Lipid secretions from algae pose a great opportunity for engineering biofueler feedstocks. The lipid exudates could be interesting from a process engineering perspective because lipids could be collected directly from the medium without harvesting and disrupting cells. We here report on the extracellular secretions of algal metabolites from the strain UTEX 2341 (Chlorella minutissima) into the culture medium. No detailed analysis of these lipid secretions has been performed to date. Using multiple mass spectrometric platforms, we observed around 1000 compounds and were able to annotate 50 lipids by means of liquid chromatography coupled to accurate mass quadrupole time-of-flight mass spectrometry (LC-QTOF), direct infusion with positive and negative electrospray ion trap mass spectrometry and gas chromatography coupled to mass spectrometry (GC-MS). These compounds were annotated by tandem mass spectral (MS/MS) database matching and retention time range filtering. We observed a series of triacylglycerols (TG), sulfoquinovosyldiacylglycerols (SQDG), phosphatidylinositols and phosphatidylglycerols, as well as betaine lipids diacylglyceryl-N,N,N-trimethylhomoserines (DGTS).
authors.affiliation: UC Davis Genome Center-Metabolomics, University of California, Davis, CA 95616, USA. tkind@ucdavis.edu
authors.forename: Tobias
authors.initials: T
authors.lastname: Kind
authors.forename: John K
authors.initials: JK
authors.lastname: Meissen
authors.forename: Dawei
authors.initials: D
authors.lastname: Yang
authors.forename: Fernando
authors.initials: F
authors.lastname: Nocito
authors.forename: Arpana
authors.initials: A
authors.lastname: Vaniya
authors.forename: Yu-Shen
authors.initials: YS
authors.lastname: Cheng
authors.forename: Jean S
authors.initials: JS
authors.lastname: Vandergheynst
authors.forename: Oliver
authors.initials: O
authors.lastname: Fiehn
mesh_terms: D056804:Biofuels; D002708:Chlorella / Q000737:chemistry* / Q000378:metabolism; D002853:Chromatography, Liquid / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D057927:Hydrophobic and Hydrophilic Interactions; D050356:Lipid Metabolism; D008055:Lipids / Q000032:analysis* / Q000737:chemistry; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D056804:Biofuels; D008055:Lipids