This review outlines the applications of capillary electrophoresis as an analytical technique for optical resolution. The brief separation principles and applications of both capillary zone electrophoresis and micellar electrokinetic chromatography for this purpose are described. Capillary zone electrophoresis using unmodified and chemically modified neutral cyclodextrins as chiral selectors added to the background electrolyte is discussed in order to separate ionic enantiomers. The chiral separation results from differences in the inclusion-complex formation of the enantiomers. The effects of the position and degree of substitution of modified cyclodextrins and the addition of modifiers to the electrolyte on the separation are presented. Micellar electrokinetic chromatography using chiral surfactants is described, where the chiral separation is achieved through differences in partitioning of the enantiomers into the chiral micellar phase. The utilization of cyclodextrins together with a micelle of common ionic surfactant, sodium dodecyl sulfate, is also briefly presented.

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Examination was made of the dialkyl-diether-type (archaeol) and trialkyl-tetraethertype (caldarchaeol-trialkyl-type) lipids, low concentrated components of lipids from Sulfolobus acidocaldarius N-8. PL-X as intact dialkyl-diether-type lipid, and PL-Y and PL-Z as intact trialkyl-tetraethertype lipids were newly found. The structure of PL-X was a diether analog of phosphatidyl inositol, and both PL-Y and PL-Z were also phosphoinositol lipids, in the former, one inositol-monophosphate was linked to glycerol on one side of the core lipid, and in the latter, inositol-monophosphates were linked to glycerols on both sides of the core. There may possibly be a pathway in which tetraether type lipids are biosynthesized through PL-Y, following the production of PL-Z from two molecules of PL-X. PL-X content constituted about 5% the total lipids ; PL-Y and PL-Z were present as less than 1% total lipids in S. acidocaldarius N-8.

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The authors developed a method for the quantitative determination of icosapentaenoic acid (IPA) and docosahexaenoic acid (DHA) in refined fish oil containing polyunsaturated fatty acids based on data obtained from a laboratory collaborative study. Three kinds of oils were (a) refined fish oil (labels specifying IPA content was 18%), (b) refined fish oil (labels specifying IPA content was 28%) and (c) mixture of (a) and (b) [50 : 50 (wt/wt)]. Methylation of triacylglyceride was carried out in a methanol solution of 2M potassium hydroxide. The tricosanoic acid methyl ester served as the internal standard for determining polyunsaturated fatty acid methyl esters by capillary gas chromatography.
All data were analyzed statistically for determination of intra- and inter-laboratory variation. IPA and DHA values were consistent with intra- and inter-laboratory coefficients of variation less than 3%. The present method is thus shown suitable for determining IPA and DHA in refined fish oil containing polyunsaturated fatty acids in excess.

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Optimal conditions for the quantitative hydrolysis of phosphatidylcholine (PC) into 1, 2-diacylglycerol (DG) were determined using little characterized phospholipase C from Bacillus sp., The hydrolysis ratio in a two-phase medium with solvent was higher than in aqueous medium. The hydrolysis of PC was accelerated in the presence of buffer consisting of disodiurn hydrogenphosphate-potassium dihydrogenphosphate at pH 7.0 and diethyl ether. The optimal conditions for hydrolysis were found to be the following ; PC-90 : 50 mg, diethyl ether : 1 mL, phosphate buffer (pH 7.0) : 6.0 mL, and phospholipase C : 0.02 Unit. PC was hydrolyzed completely within 80 min to form DG under these conditions.

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A new α-glucosidase inhibitor was isolated from an edible brown alga Hizikia fusiformis along with the known α-glucosidase inhibitor 6-sulfo-α-D-quinovopyranosyldiacylglycerol (SQDG), and was identified as 6-sulfo-α-D-quinovopyranosylmonoacylglycerol (SQMG). SQMG inhibited α-glucosidase more potently than SQDG.

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Icosapentaenoic acid (IPA) and docosahexaenoic acid (DHA) in five purified fish oils were determined by gas chromatography (GC).
These food components have recently drawn public attention, so the results were expressed as mg/g.
A DB-WAX capillary column was used for the GC, due to its greater separation efficiency. The esterification was compared using both the boron trifluoride-methanol (BF₃-methanol) method and the potassium hydroxide-methanol (KOH-methanol) method. The IPA content determined by the KOH-methanol method was found to be approximately 15% higher than by the BF₃-methanol method. The DHA content by the KOH-methanol method was also higher by 5%. Determinations of IPA and DHA by both methods showed an intra-laboratory variation of less than 2.5%.
These experimental data showed that IPA and DHA in refined fish oils can be accurately determined by capillary column GC and the esterification using KOH-methanol method.

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The modified ferric thiocyanate method was assessed for use in the determination of peroxide value (PV) of edible oils such as soybean oil, fish oil and shortening. A binary solvent system (ethanol : 1-butanol = 6 : 4 vol/vol) was used for this methods, which dissolve to transparency both oils and aqueous solution of color-producing reagents.
PV ^* of this method was based on weights of oils (S g), absorbance at 500 nm (A-As) with these of PV ^* = [4.15 (A-As) + 0.16] /10S for tested oils, where A is absorbance for sample solution, and As is that for blank solution. PV ^* results showed close agreement PV (JOCS method) in autoxidation of edible oils. This new method is applicable to the simple determination of PV of very small edible oil samples.

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