Racemic and optically active double chained cationic amphiphiles, (2 RS) -and (2 S) -N, N, N, N', N'-pentamethyl-N'- (2, 3-diacyloxypropyl) ethylenediammonium diiodides, were prepared and studied so as to clarify the influence of optical isomerism on surface and colloidal properties, such as surface tension, surface pressure and phase transition temperature.
The morphologies of the aggregates in dilute aqueous solution were investigated by electron microscopy. Well developed multilamella vesicles (MLV) and small unilamella vesicles (SUV) were readily formed from the amphiphiles, depending the conditions of sample preparation.
Phase transition temperature (T_c) of the amphiphile was examined by differential scanning calorimetry. In an amphiphile/water mixed system, optically active sinister homologs showed higher T_c than the corresponding racemates, regardless of amphiphile content.
Surface pressure measurements of amphiphiles at the air/water interface indicated the optically active isomers to always have higher surface pressure than the recemate for the same area/molecule.
The properties of aggregate in aqueous solution thus appear to be highly dependent on stereospecific orientation that is influenced by amphiphile chirality.

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Double-chain surfactants possessing two taurine units were synthesized by reaction of N-alkyltaurine (alkyl : octyl, decyl, or dodecyl) with ethylene glycol diglycidyl ether. All surfactants were soluble in water, and Krafft points were below 0°C. Cmc values were much less than those of the corresponding single-chain taurine type of compound. The isoelectric point of the title compound with two octyl chains was determined as about 5.0. Water solubility was maintained constant at the pH around the isoelectric point. Changes in some surface active properties of the double-chain compounds due to those in the pH or the addition of electrolyte are discussed.

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A simple and highly sensitive high-performance liquid chromatographic method for determining sterols in edible oils and fats is presented. Sterols were isolated from a few miligrams of sample by saponification or thin layer chromatography. They were subsequently converted into the corresponding fluorescent derivatives by heating with 9-anthroylnitrile at 100°C for 30 min in the presence of triethylamine. The derivatives were separated on a reversed phase column (Senshu pak ODS-1250-Y) with an isocratic elution using acetonitrile-dichloromethane (75/25, vol/vol). The detection limit for cholesterol was about 80 pg. The present method was shown applicable to the determination of total, free and acylated sterols in edible oils and fats with satisfactory reliability, sensitivity and handling.

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Hydrolyzed mixtures, derived from fish oil and containing free fatty acid, monoglyceride, diglyceride, and triglyceride, with hydrolysis rates about 30, 45, 60, 75 %, respectively, were applied to CPC to concentrate polyunsaturated fatty acids. Two solvents, n-hexane and acetonitrile, were used to fractionate hydrolyzed mixtures by CPC. In each case, the recovery of fractionated components exceeded 90%. In some reversed descending fractions, over 80 % of the fatty acid component consisted of icosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). More than 90 % of EPA and DHA was recovered in the reversed descending fractions. The concentrations of EPA and DHA in the reversed descending fractions increased with hydrolysis rate.

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Paper chromatography was conducted for examination of the physico-chemical effects of detergents for removing water insoluble soils on fiber assemblies without mechanical and/or hydrodynamic force. Using cellulose filter paper as the fiber assembly for the fixed phase and C.I. Disperse Blue 3 as a model of water insoluble soil, the relation between R_f' and the concentrations of surface active agents was examined.
The R_f', a measure of detergency, increased steeply near a critical micellar concentration of each surface active agent. In such a case, the longer the chain length of the alkyl group in the alkylsulfate, the lower was the concentration necessary to increase R_f' to give higher detergency. In dodecyl poly (oxyethylene) ethers, the shorter the chain length of the oxyethylene group, the lower was the concentration needed to increase R_f'. On adding NaCl to an aqueous solution of sodium dodecyl sulfate (SDS), the SDS concentration required to increase R_f' was lowered by the builder effect. Ionic surface active agents showed lower R_f' at higher temperature, while nonionic agents showed higher R_f' at high temperature.
By application of a theoretical equation to pseudophase liquid chromatography, the detergency of Disperse Blue 3 as a model of soils could be explained on the basis of the solubilization mechanism.

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Spherical particles of hydrated iron (III) oxide were prepared by the interfacial reaction method and their adhesion to polyester staple fibers was investigated in n-heptane/n-tetradecane mixtures.
The systems reached equilibrium after 48 h under weak oscillation in an incubator at various temperatures (15, 35, and 55°C).
In this study, typical Langmuir type isotherms were obtained in the soiling systems, instead of Freundlich type isotherms as nonuniform particles/cloth in the previous report.
Langmuir type adhesion was found to be exothermic in alkane mixtures.
Affinity parameters in n-heptane/n-tetradecane mixtures decreased with increasing ratio of n-tetradecane to n-heptane, and hence with increasing surface tension of dispersing medium.

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(2, 2, 3-Trimethylcyclopent-3-en-1-yl) acetaldehyde (1) was obtained by thermal decomposition of (+) -2-pinene oxide in the presence of synthetic zeolites. (1) was used as a material for the synthesis of new aromatic chemicals. The synthesis of 14 novel perfumes was carried out by introducing of functional groups as -CN, -OH, > C=O, and -COOH into (1) and the products were evaluated by professional perfumers with respect to adequacy as a perfume base. (+) -3- (2, 2, 3-Trimethylcyclopent-3-en-1-yl) propan-2-one (3) was found to be of the odor to jasmine note type derived from (+) - (2, 2, 3-trimethylcyclopent-3-en-1-yl) acetnitrile (2). α, β-Unsaturated carboxylic acid, (+) -4- (2, 2, 3-trimethylcyclopent-3-en-1-yl) -trans-2-butenoic acid (7) was of the odor to sweet sheet type. (+) -5- (2, 2, 3-Trimethylcyclopen t-3-en-1-yl) -2-methylpentan-4-ol (11), prepared by Grignard reagent addition, was of the odor to mint note type. These products were found suitable as perfume bases.

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The adsorption of cationic surfactans onto keratin powder was studies to determine differences in alkyl chain length (C₁₀C₁₈). The adsorption isotherms of C₁₀C₁₄ cationics were of the Langmuir-type. Those of C₁₆ and C₁₈ cationics showed much stronger interaction with keratin powder than those of C₁₀C₁₄ cationics. Irreversible adsorption was also observed in the former. The kinetic frictional coefficient of keratin powder-adsorbed C₁₀C₁₈ cationics was measured. For C₁₆ and C₁₈ cationics, the values were less than those of C₁₀C₁₄ cationics. The amount of saturated adsorption, the sum of both hydrophobic and irreversible adsorption, increased in the order :
C₁₄>C₁₆, C₁₈>C₁₂>C₁₀.
The antibacterial capacity of cationic surfactants against Staphylococcus aureus was assessed and interactions between cationic surfactants and ovalbumin were studied. The results in each case were found to be related to saturated adsorption. C₁₄ showed the highest activity toward Staphylococcus aureus, ovalbumin and keratin powder regarless of the type of protein.

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Although clinical attempts have been made to treat patients with senile dementia using phosphatidylcholine (PC) or acetylcholine (Ach) esterase inhibitors to restore central cholinergic transmission by increasing Ach contents in the brain, definite positive results have yet to be obtained. To investigate further the influence of the systemic administration of PC on brain Ach, we measured choline (Cho) and Ach contents in discrete brain regions of rat by HPLC with an electrochemical detector, following an acute administration of PC. Cho contents increased in the frontal cortex, striatum and substantia innomimata after acute intraperitoneal administration of soybean PC in liposome form. Cho contents were not affected in any region after acute injection of egg PC. Ach contents were not affected significantly in any brain region after acute administration of each PC substance. It thus follows that Cho contents increase by the systemic administration of highly purified PC, and PC may possibly pass the blood brain barrier. However, PC administration is not capable of accelerating Ach synthesis in the brain.

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The fatty acid specificity of a lipase in the hydrolysis of natural oils and fats can be expressed by the following equation. The hydrolysis rate H_i of a fatty acid i in a fat is H_i= (f_i/f_oi) ×H, where f_i and f_oi are the molar fractions of fatty acid i in hydrolyzed fatty acids and that in unhydrolyzed fat, respectively. H is thus the hydrolysis rate of fat by lipase. Sardine oil was hydrolyzed by a microbial lipase and the results are presented graphically.

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The development by collaborative study of a standardized method for the determination of composition of triglycerides in vegetable oils in terms of their partition numbers (or equivalent carbon numbers : ECN) by high performance liquid chromatography is described. The procedure involves the preparation of an oil sample solution, the injection in the HPLC chromatograph, the separation of triglycerides using a reversed phase polarity column and detection with an appropriate system (e.g. refractive index detector). The method allows separation triglycerides into groups of identical partition numbers and the the calculation of their relative contents.

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