Oxidative stress derived from reactive oxygen species and/or heavy metal ions causes random damages to components in living bodies, causing aging and/or various disorders. This study was undertaken in order to elucidate the molecular mechanisms of the damages to lipids, proteins and DNA caused by oxidative stress. This paper involves, lipid peroxidation induced by oxidative stress in living bodies, aging mechanisms of cells induced by oxidative stress, and OPH (oxidized protein hydrolase) as a secondary defense system against oxidative stress.

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Studies on solution properties and phase behavior of aqueous surfactant solutions, reverse vesicles, microemulsions, highly-concentrated emulsions, and cubic-phase-based micro-and macroemulsions performed in the Kunieda laboratory are overviewed.

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This review is concerning the surface-chemical properties of self-assembly created with amphiphatic compounds in view of the following three kinds of self-assemblies; monolayer-type, bilayer-type and multilayer-type. The monolayer-type corresponds to the saturated adsorption of surfactants formed at various interfaces. Adsorbed amounts of interface were observed directly by a radiotracer method using ³H-labelled compounds. The saturated adsorption of surfactants influenced the interfacial phenomena caused by the foaming, surface tension lowering and so on.
The bilayer-type is a phospholipid bilayer dispersed in water. Phospholipid dispersions were mainly DMPC, NaDMPG, and NH₄DMPG, the fundamental bilayer properties of which were precisely investigated on the effects of incubation temperature and period of aging times measured by DSC, XRD, and Zeta-potential. It was found that every phospholipids spontaneously converted into a new gel phase (Gel 2) after sufficiently hydrated with solvent water for a long period times. When hexadecane was emulsified by the state of Gel 2, the surface of emulsion was stabilized with adhesion of solubilized phospholipid bilayers, so-called three-phase emulsion, but not with adsorption of phospholipid monolayer.
The multilayer-type is a specific polymer LB film fabricated on Si-wafer after relaxated sufficiently surface pressure on the water surface. Synthetic polymer was aromatic polyether with a narrow distribution in polymerization condensation. A kind of epitaxial phenomenon was observed only on the Si-wafer surface.

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Biomass is an important resource that has been focused on as one of alternatives for petroleum.
An efficient method was devised to synthesize 2, 5-disubstituted furan compounds such as 5-chloromethyl-2-furaldehyde (CFAL) and 5-methyl-2-furaldehyde (MFAL), potent intermediates of synthetic pyrethroid using saccharides, one of biomass.
A high yield was achieved by dehydrating saccharides with hydrochloric acid either in a mixture containing water, organic solvent and a catalytic amount of a surface-active agent or in the presence of magnesium halide.
The isolation and structural determination of diketohexose dianhydrides, produced during the early stage of the reaction, were also depicted along the line.
Making use of a deoxyhalogeno-aldohexopyranose of saccharide chemistry, a simple but interesting biological active 'Indole glycoside' of a new concept, showing novel anti-tumor and immune activity, was successfully afforded.

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Organic substrates such as oils, plastics, rubbers, and lubricants are deteriorated in the presence of atmospheric oxygen. The oxidative deterioration called autoxidation is a radical chain reaction that constantly generates peroxy radicals to transfer the organic substrates to the corresponding hydroperoxides. In this article, new materials and technologies to prevent the autoxidation of the organic substrates developed by the author are reviewed. Since phenolic compounds are inhibitors of radical chain reactions, they possess antioxidant effects. Not all phenolic compounds, however, efficiently prevent the autoxidation. We found that the antioxidant effects of the phenolic compounds are drastically improved by polymerizing them. In addtition, we have developed the easy and low cost methods to control the degree of polymerization of the phenolic oligomers. Phenolic compounds having sulfide group were also prepared and some of them were found to be very strong antioxidants. The phenolic oligomers and the phenolic sulfides possess antimicrobial activities in addition to their antioxidant effects. Since the hydroperoxides are easily decomposed to generate peroxy radicals to initiate the radical chain reaction, their removal from the organic substrates prevents the autoxidation. We found that the hydroperoxides could be removed by mixing the substrates with aqueous solutions of cyclodextrins, since the hydroperoxides selectively formed inclusion complexes with cyclodextrins.

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