Total lipid contents and fatty acid composition of 13 marine fish species namely, “jenahak” (Lutianus agentimaculatus), “kebasi” (Anadontostoma chacunda), “duri” (Arius cumatranus), “tenggiri batang” (Scomberomorus commersoni), “kembong” (Rastrelliger kanagurta), “kintan” or “sebalah” (Psettodes crumei), “kerisi” (Pristipomodes typus), “kerapu” (Epinephelus sexfasciatus), “gelama kling” (Sciaena dussumieri), “malong” (Congresax talabon), “laban” (Cynoglossus lingua), “yu 9” (Scolidon sorrakowah) and “bagi” (Aacnthurs nigrosis) commonly found in Pulau Tuba, one of the islands surrounding the popular tourist destination Langkawi in Malaysia were determined. All fish showed a considerable amount of unsaturated fatty acids particularly those with 4, 5 and 6 double bonds. Two physiologically important n-3 polyunsaturated fatty acids (PUFAs), i.e. eicosapentaenoic acid (EPA) and docasahaexaenoic acid (DHA), made up of more than 50% of the total PUFAs. For saturated fatty acids, palmitic was found to be the major one in all types of fish studied. Based on DHA, EPA and arachidonic acid (AA) contents, “gelama kling” was found to be the best source (23, 11 and 7%, respectively) followed by “kerapu” (21, 10, 9%) and “sebalah” (19, 14, 4%).

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The ¹³C- and ¹H- NMR spectra of isopropyl N-dodecanoylsarcosinate (SLIP) were measured in CDCl₃, CD₃OD and in sodium dodecanoylsarcosinate (Sar) aqueous solution. The existence of both cis and trans isomeric forms are observed for SLIP just as for Sar. The trans/cis ratio of SLIP in a dilute CDCl₃ solution is over 3.2, which is indicating that SLIP-trans conformation is more stable in an organic solvent. However, the population of SLIP-trans isomer decreases in aqueous solutions. This may be explained by the interaction of the ester group and N-acyl chain. Addition of SLIP to the water/Sar solution causes the conformational change of both SLIP and Sar. With increasing SLIP concentration, the population of SLIP-trans isomer increases and Sar-cis isomer, which is known to be preferred in the monomer state, also increases. This phenomenon is discussed in the context of the phase transition behavior of SLIP/Sar/water system. At high SLIP and Sar concentration, broadening of ¹H signal relative to 2-CH₂ of Sar occurs both for trans and cis forms, however, broadening of that of Sar N-CH₂ and N-CH₃ is observed only for trans. Analysis of conformation change by NMR was proved to be useful method for phase behavior analysis of an acylamino acid surfactant.

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The aquatic risk of 2-sulfonato fatty acid methyl ester sodium salt (MES) used in household detergents was assessed. The environmental exposure assessment expressed as predicted environmental concentration (PEC) was determined on the basis of monitoring results from the seven sites of four rivers in the urban area in Tokyo and Osaka. The 95 percentile as well as geometric mean of the MES concentration was found to exhibit a good correlation with the geometric mean of the Biochemical Oxygen Demand (BOD; the latter’s regression was grater than 0.99). The predicted no effect concentration (PNEC) for the aquatic environment was estimated by performing chronic assays of algae and daphnia. The risk characterization ratio (RCR: PEC/PNEC) was less than 1. Therefore, it is concluded that MES will not adversely affect the aquatic environment in Japan.

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A novel sulfated glycosphingolipid, SGL-1, was isolated from the ascidian Ciona intestinalis, prepared from chloroform/methanol extracts and fractionated successively on DEAE Sephadex-A25, Florisil and Iatrobeads column chromatographies. Chemical structural analysis was performed using methylation analysis, gas-liquid chromatography, combined gas-liquid chromatography-mass spectrometry, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and ¹H-NMR spectroscopy. This chemical structure is presented as GlcCer I⁶-Sulfate. The ceramide moiety was specified by t16:0, t17:0, br,t17:0, t18:0 and br,t18:0 as sphingoids, and 2-hydroxy, saturated fatty acids as represented by docosanoic and tetracosanoic acids.

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The lipase-catalyzed acetylation of 2-alkanol with vinyl acetate was studied using Burkholderia cepacia lipase (BCL), three alcohol and three organic solvents in a packed-bet reactor with a recycling system (flow method). The optical resolution data were found in agreement with those of the batch method in which BCL was suspended in the substrate solution. Repeated reaction results clearly indicated BCL in the packed-bed to be quite stable and to be usable for at least 50 reaction runs or to remain effective for as long as two months in the water-insoluble solvents such as hexane and 1,2-dichloroethane. In the reaction using a water-soluble solvent such as acetonitrile, the catalytic power of BCL showed only a 1% decrease of conversion per run or solvent recycling possibly owing to compression of BCL in the bed although enantioselectivity was independent of the number of reaction repetitions. The present method showed thus be applicable to kinetic resolution by enzyme-catalyzed acylation in hydrophobic organic solvents with no waste of enzyme.

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A new calixarene-based donor-acceptor system, cone conformer 1, was prepared for the first time. In this compound, the calix[4]arene serves to juxtapose a tri-chloroquinone acceptor near the porphyrin photo-donor plane. As to the conformational control, the cone conformer 1 gave two peaks of phenolic OH groups at 8.40 and 8.43 ppm. This shows that cone conformer 1 is stabilized by intramolecular hydrogen bonds. The fluorescence intensity of 1 was 35% of that for the control compound 2. This means the trichloroquinone group in 1 efficiently quenched the fluorescence of ZnP*. The shortest edge-to-edge separation of the chromophores of 1 is ca. 8 Å (as judged by CPK models). This provides a new calixarene-based supramolecular system in which through-space donor-to-acceptor electron transfer is observed upon photoexcitation.

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Zn(II)porphyrin-substituted calix[4]arene 1 serves as molecular tweezers for 1,4-diazabicyclo[2.2.2] octane (DABCO) selectively, which led to the formation of Ensemble I. The molecular segments composing the calixarene cavity change upon inclusion of DABCO as Ensemble I were evaluated through ¹³C NMR longitudinal relaxation times (T₁) for the first time. As for Enemble I, the 1:1 complex should be formed. The T₁ values for Ensemble I are generally smaller than those for 1: in CDCl₂CDCl₂, DT1 = 5.03 s for C-1, 5.31 s for C-2, 0.13 s for C-3, 0.7 s for C-4, and 0.16 s for C-5. This substantiates that the rings of Ensemble I are firmly freezed because of the two-point coordination by DABCO. In 1, the T1 values for C-3 are always greater than those for C-4, and the difference between C-3 and C-4 is slight. As for Ensemble I, on the other hand, the difference between C-3 and C-4 is large. We can suggest two different motions for phenol units in 1 and Ensemble I: a rotational motion around a C-1 to C-4 axis (A) and a seesaw motion around a C-2 to C-2’ axis (B). The data indicate that in Ensemble I motion (A) is predominant over motion (B). This indicates that motion (B) is specifically suppressed because of the two-point coordination interactions in Ensemble I.

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