In this review, the distinction between macro- and microemulsion, properties and structure of macro- and microemulsion, the stability and breakdown of macroemulsion, the preparation (physical and/or chemical techniques) of macroemulsion, selection of emulsifier, the preparation of multiphase microemulsions, the interfacial electric phenomena in some O/W type microemulsion are discussed.

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Reactions of acrylamide (AAm) were carried out in the presence of cyclohexanone, methyl ethyl ketone and its derivatives in tetrahydorafuran at various reaction temperatures. Interactions between the carbonyl oxygen of ketones and the amide group were found to enhance the reactivity of AAm. No reactions of AAm occurred in the absence of the ketones under the same condition. Interactions of carbonyl group in the ketone with AAm could be examined directly using the ¹³C NMR spectra of a mixture of AAm and t-butyl methyl ketone or poly (methyl vinyl ketone).

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Aqueous NaCl, NaNO₃, and MgCl₂ solubilized by Aerosol OT reversed micelles in isooctane media were determined as a function of surfactant concentration. Three solubilization regions I, II and III were apparent based on chemical shifts of water at given AOT concentrations. The states of water in these regions were examined based on change in near infrared spectra with Rw (= [H₂O] / [AOT]), and were found the same in the absence of electrolytes. Water in reversed micelles was bounded, interacted with polar groups of the surfactant, and in swollen micelles, was metabounded and interacted with hydrated polar groups by hydrogen bonds. Water in W/O microemulsions was bulk-like. Based on minimal solubilized water required for swollen micelle and W/O microemulsion formation, bounded and metabounded water in reversed and swollen micelles respectively were shown not affected by these electolytes, whereas bulk-like water in W/O microemulsions was so. Electrolytes effect intensity followed the order of Cl^->NO₃^- for sodium salts and Na⁺>Mg²⁺ for chloride salts.

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β-Carotene adsorbed onto attapulgite and sepiolite in solvents with different dielectric constants was measured so as to assess the efficiency of solvent polarity for enhancing β-carotene adsorption. The solvents used were hexane, heptane, 2-methyl-pentane, cyclohexane, benzene and toluene. Negative and high correlations between dielectric constants and extent of adsorption from β-carotene, β-carotene·triolein or β-carotene·triolein·trilinolein solution were detected. Efficiency was found correlated with amount adsorbed in the case of low dielectric constant solvents (hexane or heptane) and for attapulgite and sepiolite, was 1.86. Adsorption isotherms of β-carotene for hexane, heptane or cyclohexane solution could be well expressed by the Langmuir equation. Low dielectric constant solvents in alkali-refined rapeseed oil were clearly shown to enhance bleaching efficiency.

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Prostaglandins (PG) regulate many physiological reactions and three natural PGs are presently in use for preparing obstetric and blood circulatory drugs. The chemical synthesis of these compounds is quite difficult owing to their complicated and unstable structure.
This study was carried out to determine whether biological PG synthesis could be conducted through the use of microorganisms. PG screening tests with the cultured medium were examined on 275 strains of microorganisms using the HPLC-bioassay system.
Eleven species of bacteria and fungi were found to produce PGE₁, PGE₂ and PGF_2α. Five of these species converted arachidonic acid added to the culture medium into PGE₂ and/or PGF_2α.

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For clarification of the effects of the triacylglycerol (TG) structure on volatile components produced during the autoxidation of highly unsaturated fatty acids, TG samples containing eicosapentaenoic acid (EPA) and palmitic acid (1 : 2) were autoxidized at 25°C and headspace volatiles were analyzed by gas liquid chromatography using solid phase micro-extraction method.
Hydroperoxides were produced much more during this autoxidation of EPA-containing TGs with time and increased the moles of EPA in a single TG molecule. Total amounts of volatile compounds were greatest in the case of 1 : 2 mixtures of trieicosapentaenoylglycerol and tripalmitoylglycerol (EEE/PPP (1 : 2)). The major volatile compound was 2, 4, 7-decatrienal in all unoxidized TGs. Volatile components were essentially the same for unoxidized and autoxidized 1 : 1 mixtures of dieicosapentaenoyl-palmitoylglycerol and tripalmitoylglycerol (EEP/PPP (1 : 1)), and dipalmitoyl-eicosapentaenoylglycerol (EPP), whereas many different compounds were produced in autoxidized EEE/PPP (1 : 2). 1-Propanol, 2-butenal and 2-pentenal could be detected only in autoxidized EEE/PPP (1 : 2).
The TG structure is thus shown to affect the formation of volatile compounds during the autoxidation of EPA.

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In order to understand the mechanism of the self-organization of surfactant molecules, we measured the interlayer spacings of lamellar and hexagonal liquid crystals as a function of the polyoxyethylene-chain length in water-polyoxyethylene alkyl ether systems. From these data, the effective cross sectional area per one surfactant molecule at the hydrophobic interface, α_s, is calculated. The α_s is almost independent of the hydrocarbon-chain length of surfactant, but dependent on the EO-chain length, n, and the shape of aggregates in liquid crystals. It is considered that the α_s is determined by the balance between the cohesive force (the interfacial tension) of the hydrocarbon chain and the hydration force of the EO chain. Taking into account of the steric hindrance of hydrocarbon chain at the interface (the excluded area=0.20nm² for lamellar liquid crystal) and the curvature effect of surfactant molecular layers, a new theory is proposed to calculate the α_s for the rod, the spherical and the layer aggregates. At a particular EO-chain length, the aggregate to minimize the cross-sectional area is produced. As a result, when the EO chain of surfactant is short, a lamellar structure is most stable. With increasing the EO chain, the curved surface is more stable.
Based on this theory, we also discuss about the change in the occupied surface area per one surfactant molecule at water-air interface in the aqueous surfactant solutions. Different from the self-organization in water, the occupied surface area at air-water interface obeys the equation for the flat surface even in the very long EO-chain surfactant because the curvature effect does not appear in this case.

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Margarine samples from the market in Portugal (11 brands), Belugium (12 brands), Netherlands (10 brands), the United Kingdom (12 brands), the United States (17 brands) and Japan (24 brands) were collected for determination of vitamin K₁ and dihydro-vitamin K₁ content.
1) Mean values of vitamin K₁ content were as follows : the United States, 72.1μg/100g, Japan, 47.1μg/100g, Portugal, Belgium, Netherlands and the United Kingdom, 54.1 to 68.1μg/100g.
2) Mean values of dihydro-vitamin K₁ content were as follows : Belgium, absent, Portugal, 22.2μg/100g for one brand and absent in 10 others, the United States, 62.1μg/100g, and this value exceeds all others in Netherlands, the United Kingdom and Japan (from 19.7 to 25.2μg/100g).

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