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PubMed · 12371754

A direct method for regiospecific analysis of TAG using alpha-MAG.

F Turon·P Bachain·Y Caro·M Pina·J Graille
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Abstract

An analytical procedure was developed for regiodistribution analysis of TAG using alpha-MAG prepared by an ethyl magnesium bromide deacylation. In the present communication, the deacylation procedure is shown to lead to representative alpha-MAG, allowing the composition of the native TAG in the alpha-position to be determined directly. The composition in the beta-position can then be estimated from the composition of the alpha-MAG and TAG according to the formula 3 x TAG - 2 x alpha-MAG. The estimates are superior to those obtained using the alpha,beta-DAG and Brockerhoff calculations as they come closer to the theoretical value and have smaller SD. The present procedure, first demonstrated on a synthetic TAG, was then successfully applied to the analysis of borage oil, milkfat, and tuna oil.

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AcylationChemistry Techniques, AnalyticalDietary FatsFatty AcidsFish OilsGlyceridesHydrolysisLipaseOrganometallic CompoundsPlant OilsReproducibility of ResultsStereoisomerismTriglyceridesgamma-Linolenic AcidJournal Article

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F Turon, P Bachain, Y Caro, M Pina, J Graille. 2002. A direct method for regiospecific analysis of TAG using alpha-MAG.. https://doi.org/10.1007/s11745-002-0966-3

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