About 50 kinds of new tocopherol derivatives have been synthesized, and the rates of scavenging of substituted phenoxyl radical (PhO ·), k₂, and quenching of singlet oxygen (¹O₂), k_Q, by these tocopherols have been measured spectrophotometrically in ethanol. Both the log of the rate constants, k₂ and k_Q, were found to correlate with their peak oxidation potential, E_p. The quenching rates, k_Q, were found to be related linearly to the rates k₁ and k₂ of scavenging of peroxyl (LOO ·) (reported by Burton et al.) and phenoxyl (PhO ·) radicals by these tocopherols, respectively. Vitamin K₁-chromanol and K₁-chromenol were found to be 6.9 and 4.5 times more active than α-tocopherol, respectively, which has the highest antioxidant activity among natural tocopherols. Further, the second-order rate constants, k_-1, k₃, k₄, and k₆ for the reaction of vitamin E radical with i) lipid hydroperoxides (LOOH), ii) vitamin C, iii) ubiquinol, and iv) unsaturated fatty acid esters (LH), respectively, in solution have been measured. By comparing these rate constants, the mechanism of antioxidant and prooxidant actions of tocopherols in biomembranes and edible oils has been discussed.

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Tocopherols (6 kinds) were studied by dynamic programmed thermogravimetry (TG) for weight loss and content in residual substances at 25% weight loss. The thermostability of tocopherols was also determined from temperature at which weight loss was initiated by dynamically programmed TG, and by decomposition time from the initial to 5% weight loss by isothermal programmed TG. The results are summarized as follows :
1) For dynamically programmed TG, curves for tocopherols showed characteristic weight loss patterns differing according to type of tocopherol and to atomospheric gas used in the measurement. In the nitrogen flow, weight loss was straight-forward and caused entirely by the thermal decomposition of tocopherols. However, weight loss in the air flow was complicated due to thermal decomposition accompanied by oxidative dimerization and polymerization. This was particularly remarkable above the temperature with 50% weight loss. dl-α Tocopherol was more susceptible to thermal decomposition than d-α tocopherol in the air and nitrogen.
2) Tocopherol homologue content and dl-α form in residual substances at 25% weight loss in nitrogen flow was above 94% and 70%, respectively. However, in the air flow, decrease to less than 80% was noted in both cases, the content of the dl-α form was less 40%.
3) The thermostability of tocopherol (Toc) homologues increased in the order of α-tocopherol > γ-tocopherol > δ-tocopherol based on both programmed TG and isothermal TG. The thermostability of d-α-tocopherol and dl-α tocopherol was essentially the same. Tocopheryl acetate was more stable than tocopheryl succinate.

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The dietary effects of mold oils from Mortierella ramanniana var. anglispora (IFO 8187), a lipid accumulative fungus with varying content of γ-linolenate (GLA), on plasma, liver and erythrocyte lipids in rats were examined using GLA at various concentrations and other conventional oils (palm, olive, safflower oil and tallow). The diet with mold oil caused higher arachidonate content in tissue lipids and the same growth as did the other dietary oils. A comparison of the mold oil with the control at similar (n-6) fatty acid content and comparison of mold oil with safflower oil diet indicated the possible acceleration of Δ6-desaturation by GLA and inhibition of Δ6-desaturation by high linoleate content. A dietary GLA content exceeding 10% caused decrease in the arachidonate content of tissue lipid in the rats.

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A sensitive determination of sphingolipid bases (1) was made using synthetic Cn-dihyrosphingosine and naturally occurring C₁₈- (1) aromatized with N-succinimidyl arylacetate (2a). The amino group in (1) easily reacted with (2a) to give the corresponding N-arylacetyl derivative (3a). The isomers of (1) were separated on a normal phase HPLC column in the form of (3a) which was detectable by the absorption in UV region. The isomer content of (1) as determined by the present method using (3a) having a different substituent showed agreement with that determined by GC method in the form of N-acetyl-O, O-bis (TMS) derivatives of (1) and the HPLC method in the form of N-arylcarbonyl derivative of (1), (3b).

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Assessment was made of the thermal stability of long-chain alkyl phosphate by thermal analysis (TG/DTA/DSC). Several monoalkyl phosphates (C_n-MAP) differing in chain length (C₁₂, C₁₄, C₁₆) showed essentially the same thermal stability. The decomposition temperature of didodecyl phosphate (C₁₂-DAP) was 257.8°C [40-50°C higher than that of monododecyl phosphate (C₁₂-MAP)]. C₁₂-MAP·2 Na salt was thermally more stable than C₁₂-MAP, but C₁₂-MAP·Na salt was less stable than this.
Gas chromatographic analysis of the decomposition gas indicated dodecene to be mainly formed from C₁₂-MAP, whereas 1-dodecanol from C₁₂-MAP·Na salt and C₁₂-MAP·2 Na salt.
³¹P-NMR analysis of C₁₂-MAP decomposition mixtures revealed that the disproportionation of C₁₂-MAP to phosphoric acid (PA) and C₁₂-DAP and condensed phosphate formation fromC₁₂-MAP were competetive with the elimination of olefin from C₁₂-MAP.
The elimination of olefins from monoalkyl pyrophosphate [Py- (1.0)] and dialkyl pyrophosphate [Py- (1, 1)] besides from C₁₂-MAP thus must be taken into consideration for assessement of the thermostability of long-chain alkyl phoshates. The formation of [PA+ Py- (0, 0)] from [MAP+DAP +Py- (1, 0) +Py- (1, 1)] appears to be a zero order reaction with an activation energy of 26.2kcal/mol.

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An analytical procedure was established for the identification and quantitative determination of salts of polyacrylate, acrylate-methacrylate copolymer and acrylate-maleate copolymers in household granular detergents.
The metal salts of these polymers were converted to their methyl esters by diazomethane treatment followed by extraction with chloroform to isolate them from the other components in the detergents. Quantitative determination was conducted by weighing chloroform extracts, with recovery exceeding 90%. A ¹H-NMR and pyrolysis GC-MS spectroscopy conducted in conjunction was found to be an adequate means for identifications.

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Various mixtures of soy lysophospholipids (SLPs) and fatty acid monoglycerides (MGs) were examined for properties and surface activities of their aqueous solutions. The SLPs used were mixtures of mono-and diacylphospholipid (MDPL) and the lysophosphatidylcholine (LPC) purified form of SLP.
(1) MGs were solubilized with SLPs, and their solubility increased with lysophospholipid content. Monostearin was solubilized to the greatest extent among the C₁₈ fatty acid MGs examined. An aqueous solution of an SLP/MG mixture was relatively stable under acidic and salt conditions.
(2) The water solubility of LPC/monostearin mixtures was altered by incubation at room temperature, and micellar transformation was observed to occur under an electron microscope.
(3) Decrease in surface tension of the mixture was proportional to the extent of unsaturation of the C₁₈ fatty acid of MG, and for mixtures containing the medium chain acid MG, maximum decrease in surface tension (25.5 mN/m) was observed.
(4) Aqueous solutions of SLP/MG mixtures showed significant immersion and adhesion wettability when MGs consisted of polyunsaturated and/or medium chain fatty acids.
(5) Mixtures of SLP/MG were more effective for O/W emulsification of vegetable oil compared to ordinary soy phospholipids/MG. Emulsions with SLP/MG mixtures were stable under acidic and salt conditions when SLP contained over 50% (wt/wt) LPC.
(6) Aqueous solutions of MDPL/MG mixtures showed excellent dispersibility when MDPL contained more than 40% lysophospholipids. The betha-carotene solubilizing ability of SLP decreased on adding monostearin. The above results show that suitable blend of SLP/MG can be prepared using various mixtures for specific purposes as a safe and natural surfactant.

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The surface characteristics of polystyrene-films having various fluoroalkylated ratios (Rf-ratio) were studied by contact angle and Electron Spectroscopy for Chemical Analysis (ESCA) measurements. The fluoroalkylation agents used were perfluoroalkanoyl peroxides [bis (heptafluorobutyryl) peroxides]. Critical surface tension (γ_c) of the polystyrene films decreased with increase in Rf-ratio, but remained constant above an Rf-ratio of 26%. Decrease in γc was found due to that in the London dispersion force (γ_c^d) and polar force (γ_c^p) in the components of γ_c. The effects of fluorine atoms in fluoroalkyl groups on surface characteristics (water-repellent and oil-repellent) of polystyrene were maximized even when the atoms were relatively few in number.

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An analytical method was developed for N, N-bis (2-hydroxyethyl) dodecanamide and N- (2-hydroxyethyl) dodecanamide in mixtures with dodecyl poly (oxyethylene) ethers using alumina column chromatography.
HPLC data for the mobile phase systems of the ethyl acetate with water and with methanol were found to indicate linear relationships between log k' and log (concentration of water [or methanol]) except when dodecyl poly (oxyethylene) ethers were used for methanol. An abrupt change in retention time was noted for dodecyl poly (oxyethylene) ether at a methanol concentration of about 3% in ethyl acetate. They virtually ceased to be retained regardless of the added numbers of ethylene oxide.
This elution behavior should be applicable to the development of suitable methods for the objective analysis.

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