In order to evaluate the role and the degree of counterion binding in the micelle formation of different ionic surfactants in water, the following recent studies on the counterion effects are overviewed. (i) Studies on solubility and micellization of cationic surfactants with perfluorocarboxylates as counterions and (ii) temperature studies on dodecylammonium alkanesulfonates as a function of carbon atom number in the hydrophobic counterions. Next, (iii) the mixing effects of dodecylammonium surfactants having different hydrophobic counterions, are examined for the binary mixed systems such as (A) perfluorocarboxylate vs. alkanesulfate ions and (B) perfluoroacetate vs. perfluoropropionate ions. Then, (iv) studies of the micelle properties of α, ω-type amphipiles having different types of counter-ions such as (A) α, ω-alkanediammonium bis (dodecyl sulfate) differing in alkane chain length and (B) the various surfactants consisting of α, ω-type surfactant ions and the same type counterions are introduced, and from these studies, the combination effect of the charge separations of both the surfactant ion and the counterion on the micelle properties is clarified.
Further, regarding the determination methods of critical micellization concentration (CMC) and degree of counterion binding (β), or degree of electrical dissociation of micelles (α), the results and discussion of the temperature study on α-sulfonatomyristic acid methyl (or ethyl) ester micelles by electroconductivity measurements are described. In advance of the above contents, first, theoretical aspects of micelle formation of ionic surfactants are briefly outlined.

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New fluoroalkylated end-capped co-oligomers containing oligo (oxyethylene) units were prepared by reactions of fluoroalkanoyl peroxides with oligo (oxyethylene) units -containing vinylsilane (or methacrylates) and co-monomers such as acrylic acid, dimethylacrylamide and isopropylacry-lamide. By these fluorinated co-oligomers containing oligo (oxyethylene) units, the surface tension of water could be reduced effectively with a clear break point resembling CMC and appeared to be formed intra- or inter molecular aggregates resembling micelles in water. The co-oligomers containing oli-go (oxyethylene) units were found useful for extracting various metal cations and oligomer electrolyte film containing LiCF₃SO₃ showed high ionic conductivity of 4×10^-5S/cm at room temperature. Of particular interest is the finding that the fluoroalkylated end-capped acrylic acid co-oligomers containing oligo (oxyethylene) units were found to strongly and selectively inhibit HIV-1 replication in vitro.

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Two novel series of glycosphingolipids containing inositolphosphate or methylinositolphosphate as an acidic group were found present in whole tissues of the lugworm, Tylorhynchus heterochaetus. The thin layer chromatographic pattern of the total acidic glycolipid revealed the presence of several components with positive reactions toward molybdate (phosphate) and/or both molybdate and orcinol-sulfuric acid (sugar) spray reagents. Three components (AGL₀₁, AGL₁ and AGL₂₁) were isolated and purified by successive column chromatography on two ion exchange Sephadexes and silicic acid (Iatrobeads). From structural studies including compositional sugar analysis, hydrogen fluoride degradation, boron tribromide demethylation, methylation analysis and fast atom bombardment, their structures were deduced to be as follows : AGL₀₁, InsMe (1→) -P-Cer; AGL₁, Fuc-InsMe (1→) -P-Cer; and AGL₂₁, Ins (1→) -P-Cer. The ceramide moieties of the inositollipids consisted mainly of C_{16 : 0} and C_{18 : 0} fatty acids and dihydroxy- (C_{18 : 1} and C_{18 : 0}) sphingoids for AGL₂₁, and 2-hydroxylated C_{16 : 0} and C_{18 : 0} fatty acids and trihydroxy- (C_{18 : 0}) sphingoid for AGL₀₁ and AGL₁.
In addition, their thin layer chromatographic behavior and the results of compositional anal-ysis indicated presence of at least four more inositollipids to possibly be Man-InsMe-P-Cer (AGL₂₂), Fuc-Ins-P-Cer (AGL₃), Man-Ins-P-Cer (AGL₄) and Man (Fuc-) Ins-P-Cer (AGL₅).

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Examination was made of the effects of fish diet on the fatty acid composition of the gonad of the sea urchin, Strongylocentrotus nudus using the arabesque greenling Pleurogrammus azonus containing 15.8% icosapentaenoic acid (IPA) and 9.6% docosahexaenoic acid (DHA) as the major polyunsaturates in total fatty acids of flesh lipids. The wild sea urchins contained 8.4% IPA, 8.0% arachidonic acid and 5.2% 5, 11-icosadienoic acid as the major polyunsaturates but only 1.7% DHA in total fatty acids. After feeding the fish diet for 5 months, these values became 10.2, 5.1, 4.6 and 4.5%, respectively. DHA would thus appear to be incorporated into the sea urchin gonad from the fish diet and DHA-rich sea urchin production should be possible by feeding diets with higher DHA content.

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The methyl ester of eicosapentaenoic acid (EPA) and three triglycerides containing EPA (EEE, trieicosapentaenoylglycerol; EEP, 1, 2 (or 2, 3) -dieicosapentaenoyl-3 (or 1) -palm-itoylglycerol; EPP, 1, 2 (or 2, 3) -dipalmitoyl-3 (or 1) -eicosapentaenoylglycerol) were autoxidized and their monohydroperoxide (MHP) isomers were analyzed by normal phase high-performance liquid chromatography (HPLC). Eight MHP isomers (18-, 15-, 14-, 12-, 11-, 9-, 8-, 5-position) were found in the autoxidized methyl ester of EPA and the major component was 18-MHP. Although eihgt MHP isomers were detected during the autoxidation of EEE, EEP and EPP, 5-MHP was produced in only slight amount. The lipid structure is thus shown to be a determining factor of the composition of the MHP isomers of EPA.

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Lecithin was found to be a better reaction site than CTAB micellar system for the oxidative deamination of octylamine by coenzyme PQQ under an aerobic conditions. The bimolecular layer produced by lecithin may be considered not to incorporate a substrate into the micellar hydrophobic core, in contrast to CTAB micellar system.

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