Premium
Triacylglycerols of human milk: Rapid analysis by ammonia negative ion tandem mass spectrometry
Author(s) -
Currie Graeme J.,
Kallio Heikki
Publication year - 1993
Publication title -
lipids
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.601
H-Index - 120
eISSN - 1558-9307
pISSN - 0024-4201
DOI - 10.1007/bf02536642
Subject(s) - chemistry , tandem mass spectrometry , mass spectrometry , deprotonation , mass spectrum , fatty acid , ion , ammonia , polyatomic ion , chromatography , analytical chemistry (journal) , organic chemistry
Human milk traicylglycerols (TAG) were analyzed by ammonia negative ion chemical ionization tandem mass spectrometry. The deprotonated molecular ions of triacylglycerols were fractionated at the first mass spectrometry (MS) stage. Twenty‐nine of the deprotonated TAG ions were further analyzed based on their collisionally activated (CA) spectra. The tandem MS analysis covered eleven major acyl carbon number fractions, two of which contained odd carbon number fatty acids. Fatty acids of 28 different molecular weights were recorded from the daughter spectra. Hexadecanoic acid was present in all CA spectra, octadecenoic acid in the CA spectra of all mono‐ and higher unsaturated TAG, and octadecadienoic acid in the CA spectra of all di‐ and higher unsaturated TAG. The major fatty acid combinations in triacylglycerols were: with 0 double bonds (DB), 12∶0/12∶0/16∶0; with 1 DB, 12∶0/16∶0/18∶1; with 2 DB, 16∶0/18∶1/18∶1; with 3 DB, 16∶0/18∶2/18∶1; with 4 DB, 18∶2/18∶1/18∶1; and with 5 DB, 18∶2/18∶2/18∶1; hexadecanoic acid typically occupied the sn ‐2 position. The most abundant TAG was shown to be sn ‐18∶1–16∶0–18∶1, comprising about 10% of all triacylglycerols.