Cereal Chem 59:159 - 162.  |  VIEW ARTICLE
Lipids of the Major Histological Components of Rice Studied by 13C Nuclear Magnetic Resonance Spectroscopy.

J. H. Bradbury and J. G. Collins. Copyright 1982 by the American Association of Cereal Chemists, Inc. 

13C Nuclear magnetic resonance (NMR) spectroscopy of rice and its histological components allowed the determination of 1) the amount of lipid in each component (22% in endosperm, 56% in aleurone cells plus grain coat, and 22% in embryo), 2) the amount of aleurone cells plus grain coat plus embryo (9.5%) in brown rice, 3) the ratio of saturated to unsaturated fatty acids in the embryo, endosperm, and aleurone cells plus grain coat (7.5, 6.1, and 5.4, respectively), and 4) the fact that enzyme lipase is located in the aleurone cells plus grain coat. The amount of lipid in brown rice is 3.6%, in endosperm 0.87%, in aleurone cells plus grain coat 31%, and in embryo 31.7%. The 13C NMR spectrum of lipid extracts of brown rice studied in solution was much sharper than that obtained from the solid material and allowed full evaluation of the lipid composition. The NMR results agreed with those obtained by gas chromatography and averaged, for triglyceride esters: 16:0, 25.9%; 18:1, 39.2%; and 18:2, 34.9%. At 67.89 MHz, small 13C NMR resonances were observed and were assigned to phosphatidyl choline, phosphatidyl ethanolamine, lysophosphatidyl choline, and lysophosphatidyl ethanolamine.