Several fluorescent analytical reagents for HPLC have been developed. They are 9-BrMa;pmol level determination of carboxylic acids and applied to the routine analysis of 15 common fatty acids in foods, AE-OTf ; amol level determination of carboxylic acids and applied to the determination of DSP-toxins, DPPP ; fmol level determination of hydroperoxides and applied to the determination of lipid hydroperoxides in human plasma, and (+) -TBMB-carboxylic acid ;chiral derivatization reagent for amines and alcohols at fmol level and applied to the D-, L-analysis of amino acids and glycerol derivatives. The problems in this field to be solved in future are also discussed.

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9H-Xanthene-2, 7-diols were shown to function well as hydrogen donor and suppress the oxidation of linoleic acid in homogeneous solution. In contrast to most other phenolic antioxidants these 9H-xanthene-2, 7-diols react with 26 peroxyl radicals per molecule and their antioxidant activities were close to that of α-tocopherol. The relationship of the antioxidant activity and electronic effects on stabilization of derived phenoxyl radicals were discussed.

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High performance liquid chromatographic separation of two positional triacylglycerol isomers of 1, 3-dipalmitoy1-2-oleoylglycerol (POP) and 1, 2-dipalmitoyl-3-oleoyl-rac-glycerol (PPO) as bromine or ICl adducts was carried out on a reversed stationary phase column packed with 3 μm particles of LiChrospher 100CH-18. Good separation of the triacylglycerol positional isomers required about 130 min as the bromine adduct using acetone/acetonitrile (8 : 2 vol/vol) as the mobile phase. Palm oil was analyzed by this method under similar conditions and the proportion of PPO to POP in palm oil was determined.

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The steric structures of the triacylglycerols (TGs) in the seed oil of carrot Daucus carota L. var. sativa DC. were studied by the stereospecific analysis of the acyl distributions using the chiral-phase high-performance liquid chromatography of the monoacylglycerol derivatives. Total fatty acids of the seed oil TGs contained 71 mol % petroselinic acid (6-18 : 1), 12 mol % oleic acid (9-18 : 1), 11 mol %linoleic acid (18 : 2 n-6), and 4 mol % palmitic acid (16 : 0). Fatty acid percents in each sn-1, sn-2 and sn-3 position of the TGs were 6-18 : 1 (38, 23 and 40 %), 9-18 : 1 (21, 66 and 13 %), and 18 : 2 n-6 (20, 65and 15 %). Structures and estimated contents of the major TG components in the carrot seed oil wasfound to be (6-18 : 1) (6-18 : 1) (6-18 : 1) 3248 %, (6-18 : 1) (9-18 : 1) (6-18 : 1) 1725 %, (6-18 : 1) (18 : 2 n-6) (6-18 : 1) 1522 %. Petroselinic acid distributes preferentially at the sn-1 and sn-3 positionsin the carrot seed oil TGs in analogy with 16 : 0 and 18 : 0 in the ordinary seed oil TGs.

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The dienic long-chain base (LCB), octadeca sphinga-4, 11-dienine was detected in ceramide aminoethylphosphonate (CAEP) from marine snail (Hemifusus ternatanus). To determine its structure. LCB was converted to various derivatives. The numbers of carbons and double bonds of LCB were determined by gas chromatography/mass spectrometry (GC/MS) of the trimethylsilyl (TMS) ether derivative and periodate oxidation product, an aldehyde. Double bond positions in the aliphatic chain were found by GC/MS of the TMS-polyhydroxy-N-acetyl derivative of LCB via osmium tetraoxide oxidation and the TMS-polyhydroxy-alcohol from LCB via periodate oxidation, followed by sodium borohydride reduction and osmium tetraoxide oxidation. Octadeca sphinga-4, 8-dienine were also shown present in CAEP from Hemifusus ternatanus based on the mass spectra of the TMS-polyhydroxy-N-acetyl derivative and TMS-polyhydroxy-alcohol.

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The effects of various amino acids on the membrane characteristics of liposomes were investigated in terms of particle size, encapsulating efficiency, micropolarity, and microviscosity. The particle sizes of the liposomes encapsulated buffer solutions including acidic amino acids were greater than these encapsulated buffer solutions including other amino acids. However, the encapsulating efficiencies of the liposomes encapsulated acidic amino acids were less than other liposomes. It is found that an electrostatic repulsion interaction between negative charges of the charged material (DCP) on the liposome surfaces and of the acidic amino acid in the aqueous solutions lead to looseness of orientation of lipid molecules, resulting in enhancement of their particle sizes and the micropolarity of liposomal membranes, and in decrement of the microviscosity of the membranes.

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The specificity of phospholipase D prepared from fresh cabbege leaves toward alcohols wasevaluated by transphosphatidylation between phosphatidylcholine (PC) and 15 different alcoholswith double bond or cyclic structures.
Based on the conversion ratios of PC to the corresponding phosphatidylalcohols at less than0.04 M alcohol in the water layer, whose activity was not inhibited by any alcohol, the specificityof phospholipase D was shown not to be affected by double bonds in any alcohol molecule.
The incorporation of cyclic alcohols into PC was more difficult than that of straight chainalcohols, and cyclic alcohols possessing a secondary hydroxyl group were not incorporated atall. That no inositol was incorporated into PC with phospholipase D may thus possible have beendue to inositol's possessing a cyclic structure and no primary hydroxyl group.

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The structures of molecular aggregates in monostearoylglycerol- water systems were determined primarily by small angle X-ray diffraction method. Based on the results, the phase diagram in these systems were constructed.
Some crystal phases and a gel phase were shown to exist at temperature below Tc. The phase transition between crystals was observed at about 17°C and two crystals phases were shown to exist above 17°C. The layer spaces of the crystals differed. The crystals were α and β forms according to wide angle X-ray diffraction. The a crystal was transformed to the β crystal with respect to time.
A reversed hexagonal phase was present in the region of high monoacylglycerol concentration at higher temperature than Tc. On the contrary, a lamellar phase was found at low concentration range. The lamellar phase was transformed into two different cubic phases at temperature exceeding 70°C. The cubic phase (C1) was present in more than 60 wt% of the monostearoylglycerol. The other cubic phase (C2) existed at monostearoylglycerol content below 60wt%. The size of the liquid crystals were determined in part by temperature.
With formation of the liquid crystals, it became apparent that their structures were determined primarily by the quantity of hydrated water and molecular geometry.

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The structures of molecular aggregates in monooleoylglycerol-water systems were determined primarily by small angle X-ray diffraction method. Based on the results, the phase diagram in these systems were established. The structures of monoacylglycerol aggregates were found to change significantly with respect to time.
A reversed hexagonal phase (H_II) was observed in the region of high monoacylglycerol concentration at higher temperature than Tc. The cubic phases (C1 and C2) were observed in the low concentration range. The cubic phase (C1) was found at 85 to 65 wt % monooloylglycerol, and the other cubic phase (C2) at less than 80 wt % monooloylglycerol. The cubic phases were transformed to the reversed hexagonal phase (H_II) When the temperature exceeded 80°C.
The phase diagram obtained was essentially the same as that for monostearoylglycerol-water systems at higher temperature than Tc. Molecular rotation would thus appeal to occur in the region of high temperature and it follows that the two molecules should have the same geometry, that is a determining factor of liquid crystal structure.
The cubic phases (C1 and C2), each became the reversed hexagonal phase (H _II) during several months of standing at room temperature.

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Three steroids and four phenylpropanoid glycosides were isolated from leaves of Getto (Alpinia speciosa K. Sebum), and their structures were determined based on UV, MS, ¹H-NMR, and ¹³C-NMR spectroscopic data.
The structures were β-sitosterol (1), campesterol (2), stigmasterol (3), coniferin (4), syringin (5), 2, 3-dihydro-2- (4-β-D-glucopyranosyl-3-methoxyphenyl) -3-hydroxymethyl-7-hydroxy-5-benzofranpropanol (6), and citrusin B (7). Compounds 4 and 5 showed no effect for the germination of lettuce.
All compounds isolated in this study, 17 were found in the leaves of Getto for the first time.

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