2-Arachidonoylglycerol is a unique molecular species of monoacylglycerol isolated from rat brain and canine gut as an endogenous cannabinoid receptor ligand. 2-Arachidonoylglycerol was recently shown to induce a rapid transient increase in NG108-15 cells through a cannabinoid CB1 receptor-dependent mechanism. 2-Arachidonoylglycerol was also shown to induce a rapid transient increase in HL-60 cells through a cannabinoid CB2 receptor-dependent mechanism. Based on a structure-activity relationship, 2-arachidonoylglycerol was concluded a natural ligand for the CB1 receptor or CB2 receptor and both of which are primarily 2-arachidonoylglycerol receptors. 2-Arachidonoylglycerol is a degradation product of inositol phospholipids in stimulated tissue. The CB1 receptor is involved in attenuation of the neurotransmission; 2-arachidonoylglycerol, produced and released on neuronal excitation, may possibly be essential for the slowing of neurotransmission. 2-Arachidonoylglycerol may also have important roles in the cardiovascular and immune systems, but this remains to be confirmed. A complete understanding of the physiological roles of 2-arachidonoylglycerol, a novel lipid mediator, awaits future studies.

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Bis (ammonium bromide) cleavable surfactants each bearing two ester groups were easily prepared by the acid-catalyzed esterification of 1-O-alkylglycerols with bromoacetic acids followed by reaction with amine. The surfactants showed better water solubility, better micelle formation and greater ability to lower surface tension compared to dodecyltrimethylammonium and hexadecyltrimethylammonium bromides, and their decomposition occurred more readily than bis (sodium sulfonates) at 0.01M sodium deuteroxide (NaOD). Biodegradability was more extensive compared to conventional quaternary ammonium surfactants. The compounds, obtained by chemodecomposition of cleavable surfactants, underwent greater biodegradability than the corresponding original surfactants.

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Ethyl docosahexaenoate (E-DHA) was efficiently enriched by selective alcoholysis of ethyl esters from tuna oil with lauryl alcohol (LauOH) using immobilized Rhizomucor miehei lipase. We thus attempted the development of an enzymatic process applicable to the industrial purification of E-DHA. The amount of LauOH was found the most important factor in the alcoholysis, and a larger amount of LauOH was effective for the enrichment of E-DHA. In this study, the amount was fixed at 7 molar equivalents for ethyl esters originating from tuna oil (E-DHA55; E-DHA content, 54.6mol%). A substrate mixture of E-DHA55/LauOH was introduced into a column packed with 8.0g of immobilized Rhizomucor lipase (22×63mm) at 30°C and a flow rate of 10mL/h (8.3g/h). E-DHA content increased to 87mol% with 58% alcoholysis. Even after 150 d, E-DHA content increased to 85mol%, although alcoholysis decreased to 48%. The half life of the lipase was determined as 150 d based on decrease in alcoholysis in the batch reaction. The reaction mixture flowing from the column was applied to film distillation, and unreacted ethyl esters were recovered in 82% yield. The ethyl ester fraction was contaminated with 2.4wt% LauOH and 6.3wt% lauryl esters, and lauryl esters could be completely removed by urea adduct fractionation. Through a series of purifications, E-DHA content was raised to 88wt% in 52% yield of the initial content in E-DHA55.

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Multi-alkylated surfactants of cotelomers of alkyl acrylate and acrylic acid (xR_mA-yAA; x, y and m mean number of alkyl chains, number of hydrophilic functions and alkyl chain length, respectively) were prepared by cotelomerization of n-hexyl acrylate, 2-ethylhexyl acrylate or n-dodecyl acrylate and acrylic acid in the presence of 2-aminoethanethiol hydrochloride and examined for surface activity. Surface tension of aqueous solution of xR₆A-yAA, xR₈A-yAA and xR₁₂A-yAA was 28-32, 27-30 and 38-45mN m^-1, respectively. Critical micelle concentration (cmc) decreased with greater number of alkyl chains and alkyl chain length in xR₆A-yAA, xR₈A-yAA and xR₁₂A-yAA. 2.9R₆A-2.3AA, 2.8R₈A-2.5AA and 2.7R₁₂A-2.9AA in the presence of 300ppm of Ca²⁺ exhibited surface tension of 24, 28 and 33mN m^-1, respectively. 2.9R₆A-2.3AA, possessing shorter alkyl chains, had high foam stability, while 2.8R₈A-2.5AA, having branched alkyl chains, showed poor stability. Interface between aqueous solution of xR₆A-yAA, xR₈A-yAA and xR₁₂A-yAA and toluene indicated interfacial tension of 11-13, 8-12 and 10-15mN m^-1, respectively. Cmcs of cotelomers at the interface were 1/3 to 1/4 that of sodium n-dodecanoate, a conventional surfactant. Emulsification of toluene was brought about by shaking with aqueous solution of cotelomers. A highly stable oil-in-water type emulsion was formed on using cotelomers having 2 to 3 alkyl chains.

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Crystallization rates of n-hexadecane dispersed oil-in-water (O/W) emulsion were studied by ultrasonic velocity measurement, differential scanning calorimetry and synchrotron X-ray diffraction. The hydrophobic food emulsifier, polyglycerol ester possessing a stearic acid moiety (DAS-750), was added to n-hexadecane as an impurity, to determine what effect it would have on the rate of the crystallization of n-hexadecane. A comparison of results obtained with O/W emulsion systems with those by bulk systems, indicated the following; (a) the addition of DAS-750 accelerated nucleation in the emulsion but not bulk system, (b) crystal growth rates were retarded by DAS-750. These results are discussed in terms of heterogeneous nucleation at interfaces of O/W emulsion droplets.

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Nucleophilic substitution of nitrobenzene derivatives with various amines was conducted so as to clarify the effects of W/O microemulsion surface on reaction rates. In W/O microemulsions produced in octane by sodium bis (2-ethylhexyl) sulfosuccinate (AOT) or cetyltrimethylammonium bromide (CTAB), water-soluble sodium 2, 4, 6-trinitrobenzenesulfonate or octane-soluble 2, 4-dinitrofluorobenzene was found to react with either a water-soluble amine (sodium β-aminoethane sulfonate, sodium glycine, or sodium phenylalanine), or an octane-soluble amine (benzylamine, 1-phenylethylamine, or octylamine). Reaction rate was dependent on ionic charge of surfactant and reagents, surfactant concentration, and [water] / [surfactant] molar concentration ratio (w). Based on a pseudo-phase model, the present results were explained as arising from local concentrations of nitrobenzene derivative and amine at the microemulsion surface due to electrostatic binding of ionic reactants and amphiphilic binding of neutral reactants.

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Poly (butylene succinate) copolymerized with monoacylglycerol was produced from dimethyl succinate, 1, 4-butanediol and a monoacylglycerol such as monolaurin, monostearin, and monoolein. ¹H NMR spectra of copolymers obtained using monolaurin clearly indicated the laurate component to be present in the copolymers. Gelation occurred and the copolymers were insoluble in chloroform when more than 1mol% monolaurin to dimethyl succinate was used for copolymerization owing to transesterification of a portion of the laurate component. For copolymers containing 0.3mol% monostearin or monoolein to dimethyl succinate, break stress of the copolymers was three times that of the PBS homopolymer, though the number average molecular weight and thermal properties of copolymer were the same as those of the homopolymer.

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Conjugated carbonyls each with a prostaglandin-like hydroxycyclopentanone ring were previously shown to form during autoxidation of polyunsaturated fatty acids. The carbonyls are very reactive with amino compounds and form novel red pigments when reacted with amino acids. Two stereoisomers of the carbonyl, 3- (2-ethyl-5-hydroxy-3-oxo) cyclopentyl-2-propenal, were isolated from autoxidized linolenate; their chemical structures were determined and stereochemical assignments made by ¹H- and ¹³C-nuclear magnetic resonance spectroscopy and nuclear Overhauser enhancement experiments. The isomers were shown to have different configurations of the side chains of the hydroxycyclopentanone ring. The major isomer possessed cis ring substituents although natural prostaglandins are known to have trans ring substituents.

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