SEPARATION OF GAMMA-LINOLENIC AND ALPHA-LINOLENIC ACID-CONTAINING TRIACYLGLYCEROLS BY CAPILLARY SUPERCRITICAL-FLUID CHROMATOGRAPHY

The separation of gamma- and alpha-linolenic acid containing triacylgl ycerols with an identical acyl carbon number and degree of unsaturatio n was obtained on capillary supercritical fluid chromatography using a 25% cyanopropyl-75% methylpolysiloxane stationary phase. The resoluti on of 1,3-dioleoyl-2-gamma-linolenoyl-sn-glycerol and 1,3-dioleoyl-2-a lpha-linolenoyl-sn-glycerol was 1.35 on a 10 m x 50 mu m i.d. column, whereas the resolution was enhanced to 1.66 by combining two 10-meter columns in series. The difference in the position of double bonds in o ne linolenic acid residue of triacylglycerols resulted in two series o f peaks in the separation of alpine currant (Ribes alpinum) and black currant (R. nigrum) seed oils. The use of the 10-meter column was foun d to be appropriate for the screening of the triacylglycerol profile i n both seed oils studied.