Examination was made of oxidation products of vitamin E (α-tocopherol) during the peroxidation of unsaturated lipids and decomposition of a lipid hydroperoxide. Free-radical scavenging reactions of α-tocopherol take place via the α-tocopheroxyl radical as an intermediate. Should a suitable free radical be present, a non-radical product is formed from coupling of the free radical with the α-tocopheroxyl radical. The reaction products of α-tocopherol with lipid-peroxyl radicals are 8a- (lipid-dioxy) -α-tocopherones. When the supply of oxygen is insufficient, α-tocopherol traps carbon-centered radicals of lipids to form 6-O-lipid-α-tocopherols. The dimer and trimer of α-tocopherol are formed by bimolecular self-reaction of the α-tocopheroxyl radical in a reaction mixture containing excess α-tocopherol. The reaction products of other vitamin E compounds (γ-and δ-tocopherols) with lipid-peroxyl radicals are much the same as those formed from α-tocopherol. The tocopheroxyl radicals of γ-and δ-tocopherols prefer to react with each other to form dimeric products that are still possessing high capacity to function as free radical scavengers.

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An investigation was made of the effects of sodium ions for retarding the precipitation of calcium salts of α-sulfohexadecanoic acid methyl ester (SFM) under specified washing conditions. Sodium ions were noted to bind to SFM competitively with calcium ions and effectively retarded the precipitation of SFM calcium salts. At 0.49mM SFM, 0.54mM CaCl₂ and 1mM NaCl in ammonium buffer, bound counterions of SFM aggregates were almost entirely calcium and the aggregates appeared electrically nearly neutral, each consisting of one calcium ion with two SFMs. With increase in sodium ion concentration, the sodium ions partially replaced bound calcium, with consequent enhancement of the negative charge of the aggregates. The aggregates then appeared to take on greater stability in solution from which virtually no precipitation of calcium salts was observed at least for a few hours.
Significant change in aggregate stability was observed with increase in sodium chloride concentration from 30mM to 100mM. At 100mM, bound calcium ions were far fewer than the number determined at less than 30mM. Discontinuous change in aggregate structure to result in greater stability thus appears to occur as a function of sodium chloride concentration.

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The gradual precipitation of surfactant calcium salts was observed from solutions of linear alkylbenzene sulfonate (LAS) and α-sulfohexadecanoic acid methyl ester (SFM) where either was the sole surfactant in the presence of calcium ions. When LAS and SFM were present in the same solution, their precipitation was retarded and detergency enhanced. In the present study, an investigation was made of interactions between LAS and SFM. Based on thermodynamic considerations, the influence of SFM on the alkyl distribution of LAS as monomer was predicted. It was considered that, should a mixed aggregate of LAS and SFM be formed in the presence of calcium ions, the surfactant with the lower alkyl chain of LAS would constitute the greater part of the monomer. The alkyl length distribution of monomeric LAS was determined from the initial permeation rate of each LAS constituent in solution in a semipermeable tube, this rate being assumed proportional to monomer concentration. LAS monomer was measured in various solutions with and without calcium ions or SFM. Experimental data confirmed the formation of mixed aggregates of LAS and SFM which we concluded to be responsible for preventing the precipitation of LAS and SFM in solution containing calcium ions.

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Following the addition of p-cresol (1) to aqueous solution of ferric chloride (FeCl₃), direct-liked oligomers of 1 were produced by oxidative coupling. HCl and FeCl₂, were produced during the course of the reactions, which was shown to be auto-inhibitory, in that the synergistic effect of these compounds greatly inhibited oxidation. HCl appeared to prevent the coordination of 1 with oligomers to Fe³⁺. FeCl₂ may possibly function as an competitive inhibitor by complexing with 1 and oligomers. These auto-inhibitory factors were tried to eliminate through the addition of ammonia, ethylenediamine, and pyridine. The mechanism for this elimination through ammonium salt formation is unclear though interactions with metal ions could be clearly explained based on the experimental results. Ammonia and ethylenediamine, hard bases according to the law of hard and soft ligands and metal ions, prevented oxidation. These compounds appeared strongly coordinate with Fe³⁺ (hard metal ion and oxidizing reagent) to inhibit the oxidation. Pyridine, an intermediate base, promoted the conversion of 1 to oligomers by forming a stable complex with Fe²⁺ (intermediate metal ion and the competitive inhibitor of the reaction).

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Multi-alkylated surfactants of partially-quaternized 2- or 4-vinylpyridine telomers having multi-dodecyl side chains (nL-2VPQ and nL-4VPQ; n, number of chains) were derived from telomers with polymerization degree (Pn) 5-20, prepared by the polymerization of 2- or 4-vinylpyridine in dodecanethiol as solvent, and examined for surface activity. Surface tension of the aqueous solution (pH 2) was 32-33mNm^-1 for 3.2-9.5L-2VP⁺Q with Pn 11 and 37mNm^-1 for 3.2L-4VP⁺Q with Pn 10. This parameter varied with the number of dodecyl chains and critical micellar concentration (cmc) decreased with increase in this number. Suface tension and cmc were determined in part by the particular positions of chains on the pyridine ring and polymerization degree. nL-2VP⁺Q with Pn 11 was more efficient in reduceng surface tension and depressing cmc than nL-4VP⁺Q and nL-2VP⁺Q with Pn 20. Toluene was emulsified by shaking with nL-2VP⁺Q or nL-4VP⁺Q solution. Dodecyl chain number affected the extent by emulsification and nL-2VP⁺Q with Pn 11 emulsified more than nL-2VP⁺Q with Pn 20 or nL-4VP⁺Q. Surface activity was greatest when using 3.2-6.2L-2VP⁺Q with Pn 11.

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Examination was made of GSL distribution in tissues (brain, liver and whole body) of Japanese pilchard.
The following results were obtained :
1) GSL content clearly differed according to tissue. The brain contained all GSLs in large amounts, while CSE was only sparingly present in the liver.
2) Gangliosides in the brain contained polysialoganglioside as the major component. The liver showed high concentrations of monosialogangliosides that mainly constituted GM4, thus showing a tissue-specificity.
3) This is the first report to point out the characteristic distribution of all gangliosides in the entire body of the Japanese pilchard. As a result, GM3 was the major component of it.

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Determination was made of the antioxidative activity of crude extracts obtained using organic solvents such as methyl alcohol, ethyl alcohol, acetone, hexane and ethyl acetate from Brazilian, Chinese, Australian, New Zealand and Japanese propolis (obtained between September and November, 1997).
The extracts were present as pastes and brownish-yellow in color and all contained α-tocopherol at high levels. Interactions may possibly occur between α-tocopherol and other substances since the antioxidative activity of this extract is not always in proportion to its amount.

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Four kinds of acetylenes and three kinds of terpenoids were isolated from Solidago altissima L. and characterized by MS, ¹H-NMR and ¹³C-NMR spectroscopy as methyl (Z) -decaene-4, 6, 8-triynoate (Z-dehydromatricaria esther, 1), methyl 10- [(Z) -2-methyl-2-butenoyloxy] - (2Z, 8Z) -2, 8-decadiene-4, 6-diyoate (2), (4Z) -2, 4-decadiene-6, 8-diyn-4-olide (Z-dehydromatricaria lactone, 3), (4E) -2, 4-decadiene-6, 8-diyn-4-olide (E-dehydromatricaria lactone, 4), 13E, 7α-acetoxyl kolavenic acid (solidagonic acid, 5), kolavenol (6), and D : C-friedours-7-en-3β-ol (ilexol, 7). Bioassay of these compounds on the germination of lettuce seeds showed that compounds 1, 2, 3, 4, and 5 exhibited growth inhibitory activity, whereas compound 7 did not exhibit the activity.

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In the extraction of oil from rice bran, yield and quality of oil between enzyme pretreatment and ordinary cooking pretreatment (heat and dry) were examined. Yield of extracted oil was higher in enzyme pretreatment than in ordinary cooking pretreatment. In addition, total sterol and oryzanol contents were also higher in enzyme pretreatment. Therefore, it was suggested that the condition of rice bran had changed into the one in which the unsaponifiable matters including small amount of components effective for human body were extracted easily through enzyme pretreatment.

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