title: Extraction of lipids from microalgae using CO2-expanded methanol and liquid CO2.
abstract: The use of CO2-expanded methanol (cxMeOH) and liquid carbon dioxide (lCO2) is proposed to extract lipids from Botryococcus braunii. When compressed CO2 dissolves in methanol, the solvent expands in volume, decreases in polarity and so increases in its selectivity for biodiesel desirable lipids. Solid phase extraction of the algal extract showed that the cxMeOH extracted 21 mg of biodiesel desirable lipids per mL of organic solvent compared to 3mg/mL using either neat methanol or chloroform/methanol mixture. The non-polar lCO2 showed a high affinity for non-polar lipids. Using lCO2, it is possible to extract up to 10% neutral lipids relative to the mass of dry algae. Unlike extractions using conventional solvents, these new methods require little to no volatile, flammable, or chlorinated organic solvents.
authors.affiliation: Department of Chemistry, Queen's University, Kingston, Ontario K7L 3N6, Canada.
authors.forename: Ashok
authors.initials: A
authors.lastname: Paudel
authors.affiliation: Department of Chemistry, Queen's University, Kingston, Ontario K7L 3N6, Canada.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Jessop
authors.affiliation: Department of Chemistry, Queen's University, Kingston, Ontario K7L 3N6, Canada.
authors.forename: Spencer H
authors.initials: SH
authors.lastname: Stubbins
authors.affiliation: Department of Civil Engineering, Queen's University, Kingston, Ontario K7L 3N6, Canada.
authors.forename: Pascale
authors.initials: P
authors.lastname: Champagne
authors.affiliation: Department of Chemistry, Queen's University, Kingston, Ontario K7L 3N6, Canada. Electronic address: jessop@chem.queensu.ca.
authors.forename: Philip G
authors.initials: PG
authors.lastname: Jessop
mesh_terms: D001709:Biotechnology / Q000379:methods*; D002245:Carbon Dioxide / Q000494:pharmacology*; D004952:Esters / Q000378:metabolism; D008055:Lipids / Q000302:isolation & purification*; D000432:Methanol / Q000378:metabolism*; D058086:Microalgae / Q000187:drug effects / Q000378:metabolism*; D012997:Solvents
chemical_list: D004952:Esters; D008055:Lipids; D012997:Solvents; D002245:Carbon Dioxide; D000432:Methanol
keywords: Biofuel; Botryococcus braunii; CO(2)-expanded methanol; Liquid CO(2); Microalgae