CHEMICAL-COMPOSITION OF LIPIDS, ESPECIALLY TRIACYLGLYCEROL, IN GRAPE SEEDS

Total lipids were extracted from five varieties of grape seeds and systematically analyzed for their chemical compositions. The yields of the total lipids were 10–16%, and triacylglycerol (TG) usually amounted to c. 90% of the whole. From a reversed-phase high-performance liquid Chromatographic analysis, the major molecular species of TG were shown to be trilinolein (40%), oleoyldilinolein (21%) and palmitoyldilinolein (18%). The component fatty acids were asymmetrically distributed at C-1 and C-3 of the TG molecule. Palmitic acid was exclusively located at the C-1 position, although unsaturated fatty acids, especially linoleic acid, were predominant at the C-1 position, as at the C-2 and C-3 positions. Compared with TG, higher proportions of palmitic and linolenic acids were generally observed in thirteen other lipid classes isolated from grape seeds, although the fatty acid compositions of the diacylglycerol and free fatty acids were roughly identical with that of TG. As component sterols, sitosterol, campesterol and stigmasterol, especially the former, were predominant. Their relative proportions were somewhat different from each other between the neutral and polar sterol lipids. © 1990 by the Japan Society for Bioscience, Biotechnology, and Agrochemistry. All rights reserved.