Abstract
Lipid composition and fatty acid composition of total lipids and neutral lipids extracted from seeds (kernels and seed coats) of "Yuzu" (Citrus junos SIEB. ex TANAKA), "Yuko" (Citrus yuko HORT. ex TANAKA) and "Sudachi" (Citrus sudachi HORT. ex SHIRAI) were investigated by means of silicic acid column chromatography, thin-layer chromatography and gas-liquid chromatography. The following results were obtained: (1) In the case of the above three kinds, the total lipid contents (%) were 22-24% (46-58% in dry matter) in kernels and 1-2% (2-6% in dry matter) in seed coats. (2) In three kinds, neutral lipid contents (%) in total lipids were more than 95% in kernels and more than 70% in seed coats. (3) The main lipid in neutral lipid fraction was triacylglycerol (TG, 91.5-93.1%) followed by 1, 2-diacylglycerol (1, 2-DG, 1.6-3.6%), 1, 3-diacylglycerol (1, 3-DG, 0.8-1.7%), sterol (St, 0.6-0.9%), monoacylglycerol (MG, 0.6-0.7%), free fatty acid (FFA, 0.4 -0.5%), sterol ester (SE, 0.4-0.5%) and hydrocarbon (HC, 0.2-0.3%) in kernels, and was TG (66.7-73.8%) followed by St (6.1-9.6%), MG (4.9-6.1%), 1, 2-DG (4.7-5.4%), FFA (3.0-3.4%), 1, 3-DG (2.5-2.9%), SE (1.9-24%) and HC (1.0-1.2%) in seed coats. (4) Fatty acid compositions of total lipids, neutral lipids and each component lipid (TG, 1, 2-DG, 1, 3-DG, MG, FFA and SE) of neutral lipid fraction in kernels and seed coats of three kinds were not remarkably different. The main fatty acids were C18:2, C18:2, C16:0 and C18:1 acids.
