The amounts and compositions of wax esters (WE) in various tissues of the forked hake Laemonema longipes were examined. Liver specimens containing copious amounts of lipids (72.9%) were composed almost entirely of WE (87.4%). Flesh and ovary samples contained small amounts of lipids (0.4% and 1.4%) with lower WE content (1.9 % and 13.1%, respectively). WE in the tissue lipids was found to consist mostly of C₃₈, C₃₆, C₄₀, C₃₄ and C₄₂ components (85.0-90.9%) in the carbon chain lengths. Fatty alcohols originating in WE were essentially monoenoic (89.0-95.1%) with the predominant components being 22:1 (54.0-60.9%) and 20:1 (26.7-28.1%) alcohols. Each of the monoenoic fatty alcohols comprised their isomers, and the more abundant components were 22:1n-11 (49.1-54.8%) and 20:1n-11 (21.1-22.1%) alcohols. Component fatty acids in WE from liver lipids were more monoenoic (71.8%) with 18:1n-9 (20.4%), 22:1n-11 (13.4%) and 16:1n-7 (11.8%) acids. Highly purified WE was separated from liver lipids adsorbed on silicic acid or activated aluminum oxide with n-hexane.

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Two kinds of single cell oils from thraustochytrids including Schizochytrium limacinum SR21 and Thraustochytrium sp. KK17-3 were hydrolyzed with Candida rugosa lipase to prepare the acylglycerols rich in docosahexaenoic acid (DHA, C22:6n-3). When the lipase at 800 units/g-oil was employed for a 24-h hydrolysis of SR21 oil at 37°C, DHA content in the glycerides fraction reached at up to 67.3%, being much higher than that in the original oil (40.5%), even in the absence of surfactants. In particular, monoacylglycerol contained DHA at 85.6%. After removal of free fatty acids, the glycerides fraction was further hydrolyzed to improve its DHA content to 81.3%. On the contrary, an incapability to concentrate docosapentaenoic acid (DPA, C22:5n-6) in the glycerides suggested that the lipase strictly discriminated in fine structure of respective fatty acids. Although the addition of either Triton X-100 or deoxycholate, but not Tween 20, facilitated the rapid production of monoacylglycerol rich in DHA, its accumulation level was not significantly improved. The lipase was also effective in enriching DHA (63.0%) in glycerides fraction from KK17-3 oil (30.7%). Eicosapentaenoic acid (EPA, C20:5n-3) and arachidonic acid (AA, C20:4n-6) present in this oil were released from glycerides faster than DPA and DHA by the hydrolysis. The resistance to hydrolysis of the predominant ester bonds composed of the polyunsaturates and palmitic acid (C16:0) in the oils from SR21 and KK17-3 was in the following order, DHA>>DPA>EPA>AA>C16:0. The thraustochytrid oils are therefore suitable source for the preparation of DHA-rich glycerides, especially monoglycerides.

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The physical and chemical properties of crude roselle seed oil as well as its fatty acid composition were estimated and compared with those of corn oil. Campesterol, campestanol, stigmasterol, β-sitosterol and β-sitostanol fractions (the most common phytosterols) of both oils were also determined by GLC. The results indicated that the melting point (−1.1±0.3°C), unsaponifable matter (1.0±0.2%) and iodine value (109±7) of roselle seed oil were not significantly (P<0.05) different than those of corn oil (1.0±0.1°C, 1.1±0.2% and 117±5). Therefore, the oil could be classified as semi-dry oil. The oil contained significant amounts of triacyglycerols (69.2±1.6%) and sterols (3.5±0.4%). GLC analysis proved that the linoleic (45.3%), oleic (27.2±0.7%) and palmitic (17.3±0.8%) of roselle seed oil were the predominant fatty acids. Because of the similarity of roselle seed oil to corn oil in chemical composition and lipid fractions, roselle seed oil might provide a new source of edible oil. Further study on the nutritional and physiological value of roselle seed oil is needed.

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Seven neutral glycosphingolipids were isolated and purified from the lamp shell, Lingula unguis by successive column chromatography on ion exchange Sephadex (QAE-Sephadex), magnesium silicate (Florisil) and silicic acid (Iatrobeads). Their chemical structures were characterized as Glcβ1-1ceramide (CMS₁, CMS₂ and CMS₃), Manβ1-4Glcβ1-1ceramide (MlOse₂Cer, CDS), Manα1-3Manβ1-4Glcβ1-1ceramide (MlOse₃Cer, CTS), GlcNAcβ1-2Manα1-3Manβ1-4Glcβ1-1ceramide (MlOse₄Cer, CQS) and GlcNAcβ1-4GlcNAcβ1-2Manα1-3Manβ1-4Glcβ1-1ceramide (IV⁴βGlcNAc-MlOse₄Cer, CPS) by compositional analysis, methylation analysis, exoglycosidase cleavage, gas-liquid chromatography, gas chromatograph-mass spectrometry and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Aliphatic constituents of CDS, CTS, CQS and CPS were virtually the same, with C16:0 and C18:0, and their 2-hydroxy homologues as the fatty acids, and octadecasphinga-4,8,10-trienine as the sole sphingoid. However, the ceramide compositions of CMS₁, CMS₂ and CMS₃ differed from those of the other four glycolipids. The fatty acid composition of CMS₁ consisted completely of C16:0, C17:0 and C18:0 acids, but both CMS₂ and CMS₃ contained instead of their 2-hydroxy homologues. The sphingoid components of CMS₁ and CMS₂ were octadecasphinga-4-enine and octadecasphinga-4,8,10-trienine, but that of CMS₃ was entirely trihydroxysphingoid, 4-hydroxyoctadecasphiganine.

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Three lacquer saps (Rhus vernicifera, Rhus succedanea and Melanorrhoea usitata lacquer saps) are used for a surface coating in Asia. We previously reported the identification of urushiol components in Rhus vernicifera lacquer sap (Japan, China and Korea). In this study, laccol components in Rhus succedanea lacquer sap (Vietnam and Taiwan) were synthesized by Wittig reaction of ylides derived from alkyl- and alkenylphosphonium iodides with aromatic parts such as 3-(10-oxo-1-decyl)catechol diacetate and 3-(10-oxo-1-decyl)phenol acetate, followed by removal of acetate groups. Identification of natural laccol components from Rhus succedanea lacquer saps was carried out by GC and GC/MS and comparison with synthesized laccol components. Stereostructures and constituent of all laccol components in Rhus succedanea lacquer sap were clarified. By quantitative analysis using GC, the most abundant component was 3-[(10Z, 13E, 15E)-10, 13, 15-heptadecatrienyl]catechol except for red lacquer sap, but the abundance of trienyl components was not higher than that in the Japanese lacquer sap such as Rhus vernicifera. The amount of monoenyl components were higher than in Japanese lacquer sap.

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The detergency of clay particles, the major constituent in soiled cloth, was examined in cotton using ethanol aqueous solution. With a 60% ethanol aqueous solution, detergency was minimal, this being consistent with previous data observed for detergency of silica particles on stainless steel and polyethylene mesh. ζ-potential of cotton and clay particles in ethanol aqueous solution was measured by electrophoresis of clay particles and electroosmosis of cotton cloth, respectively. Hamaker constants were obtained from surface and interfacial tension of n-hexane in ethanol solution. Minimal detergency observed in 60% ethanol aqueous solution could not be explained based on ζ-potential and Hamaker constants. Minimal penetration velocity into clay particles in a glass column was noted 60% ethanol solution, which is in agreement with detergency of clay particles in cotton in ethanol aqueous solution.

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The effects of temperature on hydrogenated yolk lecithin (HYL) dispersion were determined based on examination of flow curves and shear-jumps in oscillation rheometry, particle size, polarized microscopy and DSC.
Based on the results obtained, the following conclusions were drawn;
1) Temperature dependence of complex viscosity (η^*) for HYL-40 and HYL-60 dispersions prepared at 40°C and 60°C respectively as incubation temperatures indicated features characteristic of complex viscosity at 50°C, this temperature being related to that of the gel-liquid crystal transition of HYL, HYL-50 dispersions showed no particular features at 50°C.
2) HYL-dispersions prepared at 40°, 50°, and 60°C showed rheopexy properties at 40° and 50°C.
3) η^* vs. time curves of HYL-dispersions at ω = 0.1 rad/s indicated complex viscosity in the rheopexy region to increase with decrease in temperature owing to liquid crystalline formation of a bilayer in HYL.
4) Based on the time-dependence of complex viscosity(η^*) for HYL-dispersions as determined from shear-jump and change in the liquid crystalline bilayer of HYL, the method for flocculation was elucidated.

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Lipids in the gonads of two species of limpets from the Sanriku Coast in northern Japan were examined for lipid class and fatty acid composition. Dominant limpets were found to contain total lipids (TL) at, 1 to 2% and 5 to 6%, in the testes and ovaries, respectively. The testis was rich in phosphatidylcholine and phosphatidylethanolamine was found present. Triacylglycerol (TG) was the main constituent in the ovary. Significant differences were found in the proportion of fatty acid components of TL for those two organs. Icosapentaenoic acid (20:5n-3) was the most abundant fatty acid in the testis, with palmitic acid (16:0) being so in the ovary. Predominant fatty acids (>10% of total fatty acids in TL) generally contained 16:0, vaccenic acid (18:1n-7) and 20:5n-3 and 16:0, 18:1n-7 and arachidonic acid (20:4n-6) in the testis and ovary, respectively. The testis tends to be predominantly with amount of n-3 polyunsaturated fatty acids, 20:5n-3 being particularly high, at twice that in the ovary. The ovary contained much higher saturated fatty acids, compared to testis lipids. The quantitative distribution of fatty acids in lipid classes for male and female gonads was also determined. TG in the testis and ovary were rich in saturated fatty acid with abundant 16:0. The proportions of 20:4n-6 and 20:5n-3 in TG were low compared with those in TL and phospholipids (PL). PL contained more 20:4n-6 and 20:5n-3 than TG. PL in the testis were rich in 16:0, 18:1n-7 and 20:5n-3, and rich in 16:0, 20:4n-6 and 20:5n-3 in the ovary.

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