||Stereospecific Analysis of Fish Oil Triacylglycerols by Silicic Acid HPLC Using Monoacylglycerol Analytical Intermediates
Ando, Yasuhiro ,
Matsumoto, Nobuto ,
Yoneta, YukinoTada, Naoto
41 , 2018-08-02 , 北海道大学大学院水産科学研究院
This study establishes a method for the stereospecific analysis of fish oil triacylglycerols (TAG) using silicic acid high-performance liquid chromatography (HPLC). The analysis includes partial degradation of TAG to monoacylglycerols (MAG), derivatization of MAG to (R)-(−)-1-(1-naphthyl)ethyl urethanes, fractionation of sn-1-, sn-2-, and sn-3-MAG by HPLC, and fatty acid analysis of methyl esters by gas chromatography. For the analysis of fish oil TAG, several modifications were required in the original method developed for the analysis of olive oil TAG. For the HPLC analysis, reducing the proportion of 2-propanol in the mobile phase enabled clear separation of sn-1- and sn-3-MAG, which consisted of a wide variety of fatty acids of fish origin. Another improvement that was made was purifying the fatty acid methyl esters prepared from MAG urethanes by thin-layer chromatography. Stereospecific analysis was achieved when commencing with only 1 mg of fish oil TAG. Acyl migration, which affects the accuracy of the analysis, was found to be less than 5%. Using this method, stereospecific analysis can be carried out by HPLC on a conventional silica column, in contrast to the conventional HPLC method that requires expensive chiral columns. This method can also be used for the analysis of the TAG of both common and rare fish.