Synthetic Glycolipids, which contain cyclic or acyclic suger moieties connected, in some, cases, with amino acid (s), have hydrolyzing abilities as hydrolase models. Characteristics of these models are made clear in comparison with those of other models, mainly histidine derivatives substituted with higher alkyl group (s), proposed so far. That is, synthetic glycolipids are distinguished by hydrolyzing activities that they do not need coexistence of amphiphilic substance (s) which are indispensable for other hydrolase models, that they can hydrolyze not only ester bonds, but amide and glycoside bonds which are too strong to be hydrolyzed by other models, and that, in addition to recognition of D, L-configuration of amino acides, they can recognize kinds of amino acids as well as α, β-glycoside bonds. The active site of glycolipids on hydrolyses and the effect of reaction fields on hydrolyzing activities of glycolipids are also discussed.

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Solubilization of the synthetic perfumes, eugenol, linalool, benzyl acetate, α-ionone, α-hexylcinnamaldehyde and d-limonene by the ionic surfactants, sodium dodecyl sulfate (SDS) and do-decyltrimethylammonium chloride (DTAC) and a non-ionic surfactant such as dodecyl polyoxyethylene ethers (C₁₂POE₂₀) was investigated and assessed in terms of solubilizing capacity (SC) of the surfactants. For the same perfume, except for LN, SC followed the order, C₁₂POE₂₀>SDS>DTAC. On the other hand, the order of SC for LN was C₁₂POE₂₀>DTA>SDS. The relative importance of micelle-perfume interactions and of volume of effective solubilization site in micelle may be explanation for these findings.

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Anionic (DBS), cationic (CTAB, BTDAC, C₁₂-PC), non-ionic (C₁₂E5, N-DHA) and amphoteric (C₁₂-betaine, C₁₂-amidobetaine, C₁₂-HAA) surfactants were photodegraded in TiO₂ semiconductor suspensions under UV irradiation. Dependence of the rate of photodegradation on the chemical structure was investigated based on temporary variation of total organic carbon (TOC) in photodegraded solution. Differences in the photocatalytic effect of other metal-oxide catalysts such as ZnO, W03, TiO₂ (anatase or rutile), TiO₂ (UV-100) and TiO₂ (T-805) were also examined. TiO₂ (anatase) and Zn0 showed superior catalytic activity. TOC decreased with increase in irradiation time, since the surfactants were oxidized with the consequent evolution of CO₂ gas. TOC in solution after sonication without exposure to UV was less than that of the starting solution, indicating that surfactant to be preadsorbed on the TiO₂ surface. The rate of photodegradation of the anionic surfactants was greater than for the nonionic, cationic and amphoteric surfactants. The increase in concentration caused decrease in the photodegradation rate. From the results of laser flash photolysis using colloidal TiO₂ and benzene sulfonate (BS), the surfactant is implicated in the scavenging of the charge carrier, thereby producing either a ground-state BS⁺ cation radicals or ·OH adducts with the benzene ring of BS.

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Triacylglycerol (TG) composition of vegetable oils was determined precisely by HPLC to establish new means for identifying the components of oil-admixture. Gradient elution and two ODS columns were used to obtain high resolution for critical pair separation. A flame ionization detector was used in consideration of its response independency on unsaturation of TG species and suitableness to gradient elution. Each vegetable oil was found to have characteristic TG composition useful for oil identification. This technique was applicable mixtures of two or three oils and no analysis of minor components was required. The limit of detection was less than 10 % for palm, soybean and rapeseed oils, and 1020% for other oils.

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The radical cyclo-co-oligomerization of fluoroalkanoyl peroxides with 1, 3-diviny1-1, 1, 3, 3-tetramethyldisiloxane and acrylic acid was found to afford new fluoroalkylated silicon co-oligomers containing the 1, 1, 3, 3-tetramethyl-1, 3-disila-2-oxacyclohexane unit in excellent to moderate yields under very mild conditions. The fluorosilicon co-oligomers were soluble not only in water but common organic solvents such as methanol, ethanol, tetrahydrofuran, N, N-dimethylformamide and dimethyl sulfoxide, as well. Interestingly, these co-oligomers became soluble even in non-polar aromatic solvents such as benzene, toluene, and xylene. The fluorinated oligomers were able to reduce the surface tension of water effectively and to give rise to good oil-repellency on the surface, thus showing them to have properties typical of amphiphilic compounds. The co-oligomers were observed to inhibit HIV-1; human immunodeficiency virus type 1 induced cytopathogenesis in vitro.

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Fatty acid selectivity of 4 kinds of microbial lipases for esterification were evaluated by using different fatty acids and glycerol. Those lipases such as lipase OF from Candida cylindracea, lipozyme from Mucor miehei, lipase F from Rhizopus sp. and lipase M from Mucor javanicus showed the fatty acid selectivity as follows ; for C₁₈ fatty acids such as stearic, oleic, linoleic and linolenic acids, lipase OF, lipozyme and lipase F tend to esterify easily in order of C_{18 : 1}≥ C_{18 : 2}≥ C_{18 : 3}> C_{18 : 0}, but lipase M tends to C_{18 : 3} ≥ C_{18 : 2} ≥ C_{18 : 1}> C_{18 : 0}.
On the other hand, lipase OF tends to introduce into glycerol preferentially medium chain saturated fatty acids than long chain acids, namely C_{12 : 0}>C_{14 : 0}>C_{16 : 0} > C_{18 : 0}, but lipozyme shows no selectivity for these saturated fatty acids.
For polyunsaturated fatty acids such as icosapentaenoic acid (EPA, C_{20 : 5}) and docosahexaenoic acid (DHA, C_{22 : 6}), DHA was found to be esterified with glycerol using only lipase M in relatively high ratio, although all lipases used hardly introduce polyunsaturated fatty acids, especially DHA, into glycerol than C_{18 : 1}.

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Cerebroside was isolated from Maitake mushroom (Glifola frondosa) as the major glycolipid, and its representative molecular species of ceramide residues was characterized as N-hydroxypalmitoyl-9-methyl-trans-4, trans-8-sphigadienine, which was subsequently shown distributed not only in the fruiting bodies of six other basidiomycetes but mycelium of G. frondosa as well. trans-4-sphingenine and trans-4, trans-8-sphingadienine as well as trihydroxy straight-chain sphingoid bases with chain length from 18 to 20 carbons were also confirmed present in the mushroom cerebroside, although in minor amounts.

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The redox potentials of 5, 5' -biguaiazulene-3, 3' (5H, 5'H) -dione (a dimer of the monomeric 3-guaiazulenone radical) and its four unique autoxidation products were determined by cyclic voltammetry for a comparative study. The electrochemical behavior of these compounds is discussed.

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