Since cholesterol derivatives easily form supramolecular aggregation systems, they can serve as a versatile platform on which devices capable of molecular recognition, can be built through environmental amplification. In this article, aggregation properties and recognition functions of three different types of cholesterol derivatives containing crown ether, boronic acid and azobenzene are discussed in relation to there supramolecular systems such as liquid crystals, gels and monolayers at the air-water interface.

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A new amphoteric betaine-type surfactant of 3- (N' -acyl) -aminopropyl-N, N-dimethyl-N-carboxymethyl betaine (C_n-APNB) was prepared, whose biodegradation and hydrolysis pose no environmental problems. The physicochemical properties and surface activities such as critical micelle concentration (cmc), surface tension, foaming power, sedimentation and surface potential (adsorption) of TiO₂ particles in the presence of the surfactant were measured and biodegradability and antimicrobial features were also evaluated. The mixed system of C_n-APNB with soap exhibited synergistic effect on surface tension and foaming power at a weight ratio of 1 : 9. Antimicrobial activity forward Escherichia coli and Enterococcus was weakened by the introduction of an amidopropyl group and effects on the aquatic environment were minimized.

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Alcohol-ethyleneoxide (EO) /propyleneoxide (PO) adducts, synthesized by the block polymerization of higher alcohol, EO and PO using a composite metal oxide catalyst (NREPs), show quicker foaming-off than similar EO/PO adducts (BREPs) prepared using an alkaline catalyst. This rapid foaming-off appears to result from decrease in hydrophobic content, such as unreacted alcohol owing to narrow EO/PO adduct distribution, or increased molecular area at the air/water interface caused by terminal PO adduct structures of NREPs. With a branched alcohol, the foaming-off is even more rapid. NREPs are thus excellent nonionic surfactants with better biodegradability than BREPs.

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The hydrolysis of soybean phospholipid comprised of phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI) and phosphatidic acid (PA) by a phospholipase C from Bacillus sp. was studied under various conditions.
Phospholipase C hydrolyzed preferentially PC, followed by PE>PI>PA in a biphasic reaction system of diethyl ether-phosphate buffer, while in aqueous systems, it hydrolyzed preferentially PI, followed by PC>PE> PA.
PC and PE was hydrolyzed more easily in an aqueous system with phosphate buffer at pH 7.0 than with Tris-HCl buffer at pH 7.5, while the hydrolysis of PI showed a little difference between the two buffers. PA was the most difficult to be hydrolyzed in the phospholipid mixture used.
The hydrolysis in the biphasic system of diethylether-phosphate buffer by phospholipase C from Bacillus sp. would appear to be a simple and rapid means for concentrating PI from a phospholipid mixture.

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The presence of sphingomyelin as phospholipid in lower animals is quite rare but characteristic of higher animals. This paper describes isolation and structural characterization of two sphingomyelins, Sph.-1 and Sph.-2 from the parasitic nematode, Ascaris suum. The chemical structures were completely characterized by fatty acid and sphingoid analyses, hydrogen fluoride degradation, acid hydrolysis, enzymatic hydrolysis, infrared analysis and fast atom bombardment mass spectrometry. The ceramide moieties of the sphingomyelins consisted primarily of C_{22 : 0} and C_{24 : 0} fatty acids and branched dihydroxy- (C_{17 : 0} and C_{19 : 0}) and trihydroxy- (C_{17 : 0}) sphingoids for Sph.-1, and 2-hydroxylated (C_{22 : 0} and C_{24 : 0}) fatty acids and branched dihydroxy- (C_{17 : 1}) and trihydroxy- (C_{17 : 0}) sphingoids for Sph.-2.

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Lipid content, fatty acid composition and lipid class of round frigate mackerel, Auxis rochei Risso were investigated to utilize more effectively, high fat-fish which was unsuitable for Souda-bushi (boiled, smoke-dried and molded fish). Lipid content in orbital tissue of round frigate mackerel caught in Tosa Bay was found highest (3065%), while that in the gonad lowest (below 2%), throughout the entire year. Decrease in lipid content was greatest in September in the orbital, belly, and dorsal muscle tissue, while no other tissue showed seasonal variation. Main fatty acids constituted in this fish oil of every tissue were oleic, docosahexaenoic and palmitic acids. Continuous change was noted in fatty acid composition throughout the year in all tissues at 1530% for docosahexaenoic acid (DHA) and 1020% for icosapentaenoic acid (EPA). In the sample obtained in June, the main lipid classes of the orbital tissue, belly and dorsal muscles were triacylglycerol, whereas the gonad, liver and the red muscle contained much phospholipid.

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The isomerization of myrcene-6, 7-oxide (1) in the presence of various solid acid catalysts was studied.
When HSZ-360 HUA (H-Y 360) was used as catalyst, a high selectivity of 1-ethenyl-3, 3-dimethyl-7-oxabicyclo [2.2.1] heptane (2) and 2-methyl-6-methylene-7-octene-3-one (4) were found to be obtain.
When Al₂O₃-N 611 N was used as catalyst, 2-methyl-6-methylene-1, 7-octadiene-3-ol (5) was found to be in high yield.
And 4-ethenyl-6, 6-dimethyl-3-cyclohexene-1-ol (3a) and 4-ethenyl-2, 2-dimethyl-3-cyclohexene-1-ol (3b) were formed as new isomers.

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The critical micelle concentrations of homologs of 2- (perfluoroalkyl) ethyl sulfate salts C_nF_2n+1C₂H₄SO₄M (M=Li, n=4, 6, 8, 10 ; M= Na, n=4, 6, 8) and, for comparison, of alkyl sulfate salts C_mH_2m+1SO₄M (M=Li, Na, m=8, 10, 12, 14) in water were measured, and the values of cmc at 25 °C are expressed in the form, log cmc=A+Bn (or m). The B values of C_nF_2n+1 C₂H₄SO₄M are -0.44 ; this means that the values of cmc decrease by the factor of about 2.8 for each CF₂ group added to the perfluoroalkyl chain. The ratios of the values of B between C_nF_{2n + 1} C₂H₄SO₄M and C_mH_2m+1SO₄M were about 1.5. It may be noted that the values of cmc for C_nF_2n+1C₂H₄SO₄M correspond roughly to the cmc values of C_mH_2m+1SO₄M with m=1.5 n+2. The Krafft points of C₈F₁₇C₂H₄SO₄Na and C₁₀F₂₁C₂H₄SO₄Na in water were found to be 46 and 67 °C, respectively.

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