The application of supercritical fluid chromatography (SFC) to lipid separation is reviewed. Both capillary and packed column SFC have been extensively used in the separation of nonpolar and less polar lipids, and the published data are summarized in this paper. The separation behavior of fatty acids and triacylglycerols in SFC is discussed in comparison with that in gas chromatography and liquid chromatography. This report also describes some applications of preparative SFC to the fractionation of high value constituents contained in natural lipids.

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The authors established a method for estimating the mixing ratios of oil mixtures on the basis of their fatty acid composition data by maximum likelihood estimation. Only mean composition data of pure oil samples were used in the previous method, while variance data are also considered in this method. This method was applied to the binary mixture data of sesame oil and other oil (soybean oil, rapeseed oil and rice bran oil). The positive effect of usage of variance data was confirmed by a verification method, which was also established in this paper.

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An aerobic oxidation of squalene was carried out in a flow reactor system. Six peroxides obtained by this process were subjected by HPLC with UV, chemical luminescence detectors and iodometry. The oxidation was similar to that in the batch reactor system in which two periods of oxidation (induction and acceleration periods) were observed. In the acceleration period after the induction, squalene was oxidized by the series reactions with very high rates to form six peroxides. The peroxides were further decomposed and polymerized to carboxylic acids, ketones, aldehydes and high molecular weight products as tetramer.

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The rate of the oxidation of squalene was examined in the batch reactor, in which oxygen consumption was continuously measured to compute peroxide formed. Two oxidation steps were observed in the systems. The rate for the later of these periods (hereafter called acceleration period) is greater than 10³ times of that of the early (hereafter called induction) of them. The time length for the induction periods decreased with the reaction temperature and the concentration of unreacted sites. The overall rates of both period were expressed by the first order of the concentration of unreacted sites. The reaction process of both periods were interpreted by some steps of the excitation of reaction sites and chain reactions for excited species. The reaction constants for both reactions were determined by the function of temperature.

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Alkyliminodiacetate is a surfactant recently developed for toiletry application.
The solution properties of alkyliminodiacetate were examined by measuring the Krafft point, surface tension of the surfactant solution, foaming power, wetting ability and Ca tolerance. The relation between there properties and surfactant structure was sought by comparing the results of alkyliminodiacetate with different length of alkyl chain, alkylaminoacetate, alkylaminopropionate and alkyliminodipropionate.
Clarification was made of the following ; 1) the Krafft point of alkyliminodiacetate is much lower than that of alkylaminoacetate, 2) alkyliminodiacetate is more hydrophilic than alkylaminoacetate, 3) the foaming power of alkyliminodiacetate is sufficient, 4) the wetting ability of alkylimino-diacetate increases with length of the alkyl chain, 5) the Ca tolerance suggests the mechanism of chelating metals of disodium alkyliminodiacetate to differ from that of monosodium alkyliminodiacetate.

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The surfactant content of commercial laundry detergents in Japan and the United States was determined and their ingredients, description on label, detergency, and the typical washing conditions in Japan and the United States were compared. When the surfactant content in compact powder detergents, which category is now leading in both countries, is compared, the content in the Japanese detergents is generally larger than that in the U.S. The American detergents showed higher detergency than the Japanese in the same category, especially at high water hardness. The volume of water, detergent dosage, the amount of builder and the fabric load per wash in the U.S. are about 1.6 times to those in Japan.

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Aliphatic polyesters hold promise as biodegradable plastics. However, aliphatic polyesters with number average molecular weight (Mn) exceeding 10000 still cannot be obtained in all cases by the polycondensation of dicarboxylic acids (or diesters) with diols. To achieve this purpose, chain extension (bridging) reactions of lower molecular weight polyesters synthesized from various diesters and diols were carried out in the present study.
The diesters used were dimethyl succinate (DMS), dimethyl adipate (DMA), and dimethyl suberate (DMSb) and the diols were ethylene glycol (EG), 1, 4-butanediol (BD), and 1, 6-hexanediol (HD). The polyesters prepared from EG with diesters were not used in the present chain extension reactions becaus of their low yield and molecular weight. When chain extension of all polyesters was carried out under the optimum conditions determined preliminarily using hexamethylene diisocyanate (HMD) as the chain extender, Mn of the polyesters exceeded that prior to chain extension by a factor of 2, and all chain extended polyesters except DMA/BD polyester were film-formable. At least one of two end-groups of the original polyesters would thus appear to be a hydroxy group (-OH), and reaction between this end-group and isocyanate group of HMD may produce urethane bonds, indicating efficient chain extension.
Changes in thermal properties and enzymatic degradation by cholesterol esterase of the polyesters were also studied before and after chain extension. These parameters, however, generally remained essentially the same as those of the original polyesters. The enzymatic degradation of DMS/BD polyester was considerably less than that of other polyesters, its melting point (ca. 116°C) being much higher than those (5060°C) of the others.

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Examination was made by the effects of antioxidative activity of phenolic compounds isolated from Boreava orientalis fruit (Cruciferae) and related compounds on free radical-oxidation of methyl linolate in solution. Based on methyl linolate hydroperoxide production using 2, 2'-azobis (2, 4-dimethyl valeronitrile) (AMVN) as the radical initiator. Dihydroxybenzoic acids and phenylpropanoids, particularly cinnamic acid derivatives, were shown to be strong antioxidatnts.

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Cytokine (interleukin ; IL) release related dermal acute inflammation was measured for normal human epidermal keratinocyte treated with lauryliminodiacetate (LIDA) and analogous surfactants. The relation of IL with surfactants was examined.
Cytotoxicity introduced by LIDA appears involved in the release of IL-1α and IL-8, while no remarkable release of IL-1 α and IL-6 could be detected for lauryliminodipropionate (LIDP) at essentially the same concentration. For laurylaminoacetate (LAA) and laurylaminopropionate (LAP), greater IL-1 a and IL-6 release than LIDP was noted, indicating higher cytotoxicity. With sodium lauryl sulfate (SLS), IL-1α, IL-6 and IL-8 release was largest.

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Study was made to determine the relation between the introduction of the perfluorooctyl group (Rf) into epoxy resin and its properties. When Rf was present at a few % in acidanhydride-cured epoxy resin, its contact angle increased by 20 degrees. Compounds examined in this study to introduce Rf groups into epoxy resins were (1) : 8 (9) - [2- (perfluorooctyl) ethoxy] tricyclo [5.2.1.0^{2, 6}] decane-3, 4-epoxide and (2) : a derivative of (1) which had a hydroxyl group. When reacted with acid anhydride to preparate acid-anhydride-cured epoxy resin, (1) did not react with the anhydrides, whereas (2) was successfully incorporated into the resin.

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