title: Multicomponent analysis of encapsulated marine oil supplements using high-resolution 1H and 13C NMR techniques.
abstract: Multicomponent high-resolution 1H and 13C NMR analysis has been employed for the purpose of detecting and quantifying a wide range of fatty acids (as triacylglycerols or otherwise) in encapsulated marine cod liver oil supplements. The 1H NMR technique provided quantitative data regarding the docosahexaenoic acid content of these products, which serves as a valuable index of fish oil quality, and a combination of both 1H and 13C spectroscopies permitted the analysis of many further components therein, including sn-1 monoacylglycerols, sn-1,2 and -1,3 diacylglycerol adducts, together with a range of minor components, such as trans-fatty acids, free glycerol and cholesterol, and added vitamins A and E. The identities of each of the above agents were confirmed by the application of two-dimensional 1H-1H spectroscopies. The NMR techniques employed also uniquely permitted determinations of the content of nonacylglycerol forms of highly unsaturated (or other) fatty acids in these products (i.e., ethyl esters), and therefore served as a means of distinguishing "natural" sources of cod liver oils from those subjected to chemical modification to and/or supplementation with synthetic derivatives such as ethyl docosahexaenoate or eicosopentaenoate. The analytical significance and putative health effects of the results acquired are discussed.
authors.affiliation: Department of Diabetes and Metabolic Medicine, Barts and the London, Queen Mary's School of Medicine and Dentistry, Whitechapel, London E1 1BB, United Kingdom.
authors.forename: Navaede
authors.initials: N
authors.lastname: Siddiqui
authors.forename: Julia
authors.initials: J
authors.lastname: Sim
authors.forename: Christopher J L
authors.initials: CJ
authors.lastname: Silwood
authors.forename: Harold
authors.initials: H
authors.lastname: Toms
authors.forename: Richard A
authors.initials: RA
authors.lastname: Iles
authors.forename: Martin
authors.initials: M
authors.lastname: Grootveld
mesh_terms: D003060:Cod Liver Oil / Q000737:chemistry*; D019587:Dietary Supplements; D005227:Fatty Acids / Q000032:analysis*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure
chemical_list: D005227:Fatty Acids; D003060:Cod Liver Oil