title: Optimization of a single phase method for lipid extraction from milk.
abstract: For LC-MS-based lipidomic analysis of milk, total lipid extraction from raw milk is generally conducted with Folch or Bligh and Dyer methods; both methods are based on two-phase partition of lipids, and thus time-consuming. In this work, three solvent systems for one-phase extraction of milk lipids were compared with the standard Folch method. Two of the solvent systems (butanol/methanol, 3:1 and 1:1) previously tested for lipid extraction from plasma were found to provide adequate extraction for polar lipids, but incomplete extraction for triglycerides, especially highly lipophilic species. By contrast, our newly designed solvent mix composed of butanol, methanol and chloroform (at a 3:5:4 ratio) provided similar extraction efficiency for triglycerides and higher yield for some of the phospholipids, as compared to the Folch method. This new one-phase extraction method is very simple yet comprehensive and thus suitable for high throughput lipid analysis of milk samples.
authors.affiliation: Biosciences Research, Department of Economic Development, Jobs, Transport and Resources, AgriBio, 5 Ring Road, Bundoora, Victoria 3083, Australia. Electronic address: Zhiqian.liu@ecodev.vic.gov.au.
authors.forename: Zhiqian
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Biosciences Research, Department of Economic Development, Jobs, Transport and Resources, AgriBio, 5 Ring Road, Bundoora, Victoria 3083, Australia; School of Applied Systems Biology, La Trobe University, Bundoora, Victoria 3083, Australia.
authors.forename: Simone
authors.initials: S
authors.lastname: Rochfort
authors.affiliation: Biosciences Research, Department of Economic Development, Jobs, Transport and Resources, AgriBio, 5 Ring Road, Bundoora, Victoria 3083, Australia; School of Applied Systems Biology, La Trobe University, Bundoora, Victoria 3083, Australia.
authors.forename: Benjamin G
authors.initials: BG
authors.lastname: Cocks
mesh_terms: D000818:Animals; D000440:Butanols / Q000737:chemistry; D002725:Chloroform / Q000737:chemistry; D002853:Chromatography, Liquid; D008055:Lipids / Q000737:chemistry* / Q000302:isolation & purification*; D013058:Mass Spectrometry / Q000379:methods*; D000432:Methanol / Q000737:chemistry; D008892:Milk / Q000737:chemistry*; D010743:Phospholipids / Q000737:chemistry / Q000302:isolation & purification; D012997:Solvents / Q000737:chemistry; D014280:Triglycerides / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D000440:Butanols; D008055:Lipids; D010743:Phospholipids; D012997:Solvents; D014280:Triglycerides; D002725:Chloroform; D000432:Methanol
keywords: Lipid; Liquid chromatography–mass spectrometry; Milk; One-phase extraction