Triacylglycerols of Vernonia galamensis seed oil

Abstract

Separation methods using silica gel column chromatography and preparative thin layer chromatography were employed to prepare pure triacylglycerol fractions of the oil from Vernonia galamensis seeds. Pure vernolic acid (12, 13-epoxy-octadec-cis-9-enoic acid) was prepared by enzymatic hydrolysis of the chromatographically purified major triacylglycerol, trivernolin, using a commercially available immobilised lipase in a non-polar organic solvent. Analysis of the divernoloyl and monovernoloyl triacylglycerols with porcine pancreatic lipase indicated that vernolic acid is found mainly as the secondary ester in the divernoloyl triacylglycerol but not the monovernoloyl triacylglycerol.