Triacylglycerols (TAGs), which are composed of three fatty acids and a glycerol, are major components of natural edible oils and fats which is an essential energy source for organisms. The physical and nutritional properties of oils and fats are affected by not only the fatty acid composition but also TAG composition. The binding position of fatty acid on the glycerol backbone is not random but dependent on the origin of the oils and fats. Although many researchers have so far studied the composition and the positional distribution of fatty acids of edible oils and fats to understand the properties of them, these data not show the compositions of intact TAGs. Analyses of TAG molecular species by GC and HPLC have also been developed and they have revealed the concrete compositions of TAGs in edible oils and fats. Recently, the separation methods for not only TAG positional isomer but also TAG enantiomers have been reported. These methods will enable the elucidation of the physical and nutritional properties due to the TAG structure in future.

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Lipid and fatty acid metabolism in human is usually measured by using whole bloods or sera of subjects and by detecting lipids and fatty acids in serum or erythrocytes with biochemical and chromatographic apparatus in clinical laboratory. On the other hand, many trials have been made for a long time to develop non-invasive diagnostic methods for monitoring lipid and fatty acid metabolism in human instantly at anywhere and anytime, especially to contribute for personal health care. For this purpose vibrational spectroscopy such as FTIR used for lipid and fatty acid measurements seems promising because of its analytical advancement and mobility. The technique of NMR spectroscopy for non-destructive measurement of human serum lipoproteins has been established and contributed to various epidemiological researches. These spectroscopic techniques are suitable for non-invasive or non-destructive and instantaneous measurements, and expected for further development of clinical measurements of lipid and fatty acid metabolism in human.

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A kinetic study of the quenching reaction of singlet oxygen (¹O₂) with 25 natural antioxidants (including 8 carotenoids, 6 tocopherol derivatives, ubiquinol-10, 3 caffeic acids, 6 catechins, and vitamin C) was performed in ethanol/chloroform/D₂O (50:50:1, v/v/v) and ethanol solutions at 35°C. The second-order rate constants, k_Q, for the reaction of antioxidants with ¹O₂ were measured, using the competition reaction method, where endoperoxide was used as a singlet oxygen generator, 2,5-diphenyl-3,4-benzofuran (DPBF) as an UV-Vis absorption prove, and α-tocopherol was used as a standard compound. The rate constants, k_Q (S) and k_Q (t_1/2), were determined by analyzing the first-order rate constant (S) and the half-life (t_1/2) of the decay curve of DPBF with antioxidants, respectively, showing good accordance with each other. The method is useful to evaluate the ¹O₂-quenching activity of lipophilic- and hydrophilic-antioxidants having five orders of magnitude different rate constants from 1.38×10¹⁰ M^－1s^－1 for lycopene to 2.71×10⁵ for ferulic acid. Similar measurements were performed for 30 kinds of food extracts including vegetable, fruit, and edible oil extracts. From the results, a new assay method which can quantify the singlet oxygen absorption capacity (SOAC) of natural antioxidants and food extracts has been proposed.

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Currently, ordered mesoporous materials prepared through the self-assembly of surfactants have attracted growing interests owing to their special properties, including uniform mesopores and a high specific surface area. Mesoporous materials now include a variety of inorganic-based materials, for example, transition-metal oxides, carbons, inorganic-organic hybrid materials, polymers, and even metals. Mesoporous metals with metallic frameworks can be produced by using surfactant-based synthesis with electrochemical methods. Owing to their metallic frameworks, mesoporous metals with high electroconductivity and high surface areas hold promise for a wide range of electrochemical applications. Development of new synthetic pathways for mesoporous (nanoporous) materials is also one of the main subjects in this rapidly developing research field. This Review summarizes recent progress in functional nanoporous materials.

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