| Abstract: | Lipids were extracted from a single sample of wheat flour using three solvent systems: ethanol–diethyl ether–water (2:2:1 by vol.); chloroform–methanol (2:1 by vol.); and water-saturated n-butanol. Analysis of the extracts and of residual lipid in the extracted flour showed that water-saturated n-butanol was the most efficient solvent. Wheat-flour lipids were extracted with water-saturated n-butanol and separated by chromatographic procedures into individual components. The lipid classes which were isolated and studied were steryl ester, free sterol, 6-O-acyl steryl glucoside, steryl glucoside, triglyceride, diglyceride, monoglyceride, free fatty acid, monogalactosyl diglyceride, 6-O-acyl monogalactosyl diglyceride, digalactosyl diglyceride, digalactosyl monoglyceride, monoglycosyl ceramide, diglycosyl ceramide, N-acyl phosphatidyl ethanolamine, N-acyl lysophosphatidyl ethanolamine, phosphatidyl ethanolamine, lysophosphatidyl ethanolamine, phosphatidyl choline, lysophosphatidyl choline, phosphatidyl serine and phosphatidyl inositol. Monogalactosyl monoglyceride was also tentatively identified. The quantitative distributions of the lipid classes were determined. Monoglycosyl ceramide contained small amounts of normal fatty acids (12:0–24:0) and large amounts of 2-hydroxy fatty acids (principally 16:0 and 20:0), with similar amounts of dihydroxy long-chain bases (18:0 and 18:1) and trihydroxy long-chain bases (18:0, 18:1, 19:0, 19:1, 20:0, 22:0). The principal sterols were identified as β-sitosterol, campesterol, and C28 and C29 saturated sterols. The fatty acids in the sterol lipids were principally 16:0 (50–60%) and 18:2 (28–30%) with small amounts of 16:1, 18:0, 18:1 and 18:3. The fatty acids in all the glycerides were principally 18:2 (51–84%) with lesser amounts of 16:0, 18:0, 18:1 and 18:3. |
