The combination method of high performance liquid chromatography / UV-Visible (Vis) absorption spectrometry by photodiode-array detector and atmospheric pressure chemical ionization mass spectrometry (LC/PAD/APCI-MS) were applied for the rapid identification of carotenoids obtained from several natural sources. APCI-MS spectra provided not only information of the molecule weight but also the presence of functional groups such as hydroxy, acetyl and glycosyl groups in carotenoids. On the other hand, UV-Vis spectra gave the information of chromophores which consist of the conjugated double bonds and end groups in carotenoids. This combination method allows the carotenoids to be characterized by retention time in HPLC, APCI-MS and UV-Vis spectral data so that it offers rapid and accurate method for the identification of carotenoids extracted from various natual sources.

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Phase diagrams for binary mixtures of sterols such as 5-cholesten-3β-ol (I), 5α-cholestan-3β-ol (II), 5β-cholestan-3α-ol (III) and 5β-cholestan-3β-ol (IV) were studied. II is similar to I in its straight, plank-like skeletal structure and in the direction of OH moiety linking directly to the steroid ring. III is similar to IV in its bending skeletal structure and differs in the direction of OH moiety from I, II and IV. From phase diagrams for all of their binary mixtures, it became clear that in I/II and also in II/IV systems the molecules of each component are phase-separated from each other in the solid state and provide a eutectic mixture. In I/III, II/III and III/IV systems, two kinds of molecules whose OH moieties are in opposite directions to each other made a 1:1 compound. On the other hand, in I/IV system I and IV molecules made an incongruent melting (peritectic) compound, which was less stable and, before its melting, decomposed into solid I and a 1:1-molar-ratio solution of I and IV at 373 K.

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Six caffeic amides 1-6 were synthesized by condensing caffeic acid (CA) with serine or lysine derivatives. Tyrosinase inhibitory and antioxidant activities were measured to find effective cosmetic ingredients. Most of the derivatives prepared showed tyrosinase inhibition stronger than or comparable to CA, the amino acids, chlorogenic acid (CGA) or arbutin, and showed antioxidant activity stronger than the most popular whitening agents, kojic acid or arbutin. N-Caffeoyl-O-acetylserine methyl ester 3 showed the strongest activity in two assay systems and proved to be a promising candidate for cosmetic ingredients.

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Nine pyrethroid pesticides and 3 organophosphorus pesticides, which could not be removed during the oil refining process, were added to refined soybean oils at concentrations of 4 ppm each, and the oils were hydrogenated under 8 different conditions, then the persistence of these pesticides was examined. As a result, it was found that pyrethrin and permethrin persisted beyond other pesticides during hydrogenation and that these 2 pesticides decreased readily at a higher temperature, at a higher hydrogen flow rate or at a higher stirring speed. It was also clarified that any pyrethrin and permethrin persisting in an oil before hydrogenation can be eliminated by performing hydrogenation until the iodine value of the soybean oil attains 70 or less. Subsequently, pyrethrin and permethrin were added to a hydrogenated soybean oil at concentrations of 3 ppm each, and the oil was deodorized under the condition commonly used in oil plants, then the behaviors of these pesticides were examined. As a result, it was observed that the pyrethrin concentration was lowered below 0.01 ppm after deodorizing for 120 minutes, while permethrin remained at 0.32 ppm in the oil.

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Cell membrane fluidity and changes of cellular lipids of U937 cells during apoptosis are compared between the cells treated with dolichyl phosphate (dol-P) and etoposide. Dol-P induced lateral cell membrane perturbation immediately after addition and continued for at least 40 min. However, etoposide induced apoptosis without increase in cell membrane fluidity. Phosphatidylethanolamine was translocated together with phosphatidylserine after 4 hr of treatment in both dol-P and etoposide treated cells. The concentration of lipid levels changed in dol-P-induced cells and the cholesterol/phospholipid ratio almost doubled. Conversely, none of the phospholipid and cholesterol levels changed in etoposide treated cells. Although both dol-P and etoposide induce apoptosis, dol-P, but not etoposide, appeared to function as a modulator of membrane fluidity and to change membrane constituents and membrane physiology during the course of apoptosis.

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Vesicle forming ability of double-chain cationic surfactants {dialkyldimethyl-ammonium bromides {(C_nH_2n+1)₂(CH₃)₂N⁺Br^-; DDAB (n=12), DTDAB (n=14), DHDAB (n=16), DODAB (n=18)} in deep sea water was examined, and the effect of their chain length on the membrane properties and dispersability of vesicles formed was investigated. Any of the surfactants failed to form vesicles in 100% of deep sea water while they formed vesicles in a mixture of deep sea water (5%)/purified water water (95%) and in deep sea water treated with reverse osmosis membrane (RO water). The particle size of vesicles was found to increase with the chain length of the cationic surfactants (except for DHDAB). For DTDAB with 14 carbon atoms in the alkyl chain, vesicles in RO water were more stable than in purified water, being stable for six months after preparation. The experimental findings demonstrated that the stability of the vesicles depended on the preparation temperature and the gel-liquid crystal phase transition temperature of the surfactants (in each system).

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The title spectra were measured at various concentrations of SDS. IER spectra demonstrated that conformational order of alkyl chains of SDS and MA and surface composition at the air/water interface was clarified. Conformational order was found to improve on increasing SDS concentration up to [SDS]=3 mM. MA showed essentially no change. The ratio of MA to SDS composition at the interface is exceeded that in bulk solution and decreased at greater SDS.

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Natural material extracts are presently used as cosmetic ingredients. Their physiological effects were examined using estragole isolated from the essential oil of Foeniculum vulgare Miller as starting materials. Thirty derivatives were synthesized by condensation using ten thiols. The derivatives were examined for potential use as whitening agents possessing tyrosinase activity and superoxide dismutase. Derivative compounds were found good inhibitors of tyrosinase.

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Lipid peroxidation and the antioxidant effects of 3,5,7,4’-tetrahydroxy-2’-methoxyflavone (THMF), isolated from the bark of Anaxagorea luzonensis A. GRAY, were observed by atomic force microscopy (AFM). The Langmuir-Blodgett film of 1-palmitoyl-2-linoleoyl-3-phosphatidylcholine (PLPC) was used for AFM. The antioxidant potency of THMF was compared with that of α-tocopherol as the positive control. The AFM images clearly indicated that THMF effectively inhibited lipid peroxidation and that the antioxidant effect of THMF was more potent than that of α-tocopherol. This is the first report of direct visual observation of the effects of an antioxidant on lipid peroxidation.

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