The eradication of cancer is one of the important research subjects for humankind toward the 21st century. In the course of our research on potent cancer chemopreventive agents from edible plants and fungi, and from crude herbal medicines, we have found that various sterols and triterpene alcohols and their oxygenated derivatives showed activity in in vivo primary screening assay of antitumor promoters by inhibiting the inflammatory ear edema induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in mice. In this review, we discussed the inhibitory activity of sterols and triterpenoids toward TPA-induced inflammatory ear edema, and tumor promotion during two-stage carcinogenesis with 7, 12-dimethylbenz [a] anthracene (DMBA) and TPA. This activity was also noted in several other assays on antitumor promoters such as that on the activation of Epstein-Barr virus by TPA, and TPA-stimulated Pi incorporation in HeLa cells. Sterols and triterpenoids are minor but ubiquitous components in the human diet, and are considered to be non-toxic. These compounds may possibly prove useful for producing cancer chemopreventive agents.

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3-ethylcyclopentanone derivatives were synthesized for examination of antibacterial activity, and it was evaluated by molecular orbital calculation.
This parameter at minimum inhibitory concentration (MIC) was found closely correlated with absolute electronegativity (χ) derived from the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO). The values of ΔN and ΔE calculated from χ and absolute hardness (η) of 3-methylcyclopentanones and amino acids also showed good correlation with MIC. In relation to methylenomycins, cyclopentanone antibiotics, antibacterial activity was investigated by comparing the χ, ΔN and ΔE.
2, 3-Epoxy-3-methyl-5-methylenecyclopentanone 4 whose antibacterial activity was the strongest, may possibly have potential as a cyclopentanone antibiotic based on χ, ΔN and ΔE data.

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We studied the γ-ray-induced polymerization of two mixed-liposome systems containing 1, 2-bis- [(2E, 4E) -octadecadienoyl] -sn-glycero-3-phosphocholine (DODPC) to clarify its mechanism; (a) containing DODPC and 1, 2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), or DODPC/DPPC liposome, and (b) containing DODPC, DPPC, Cholesterol (Chol), and stearic acid (SA), or DODPC/DPPC/Chol/SA liposomes was carried out. For each system, various molar ratios of DODPC/DPPC were studied. For DODPC/DPPC/Chol/SA liposomes, the molar ratio of phospholipid/Chol/SA was 7/7/2. Liposomes were prepared by extrusion through a 0.2-μm-pore polycarbonate filter and polymerized by γ-irradiation at a dose rate of 3.3kGy/h at 4°C. Polymerization rate increased when DODPC/DPPC was 5/5 in DODPC/DPPC liposomes and when it was 9/1, 8/2, 7/3, and 5/5 in DODPC/DPPC/Chol/SA liposomes. The degree of polymerization at molar ratio 5/5 for each mixed-liposome system significantly increased compared with that of DODPC liposomes containing no DPPC. For polymerized mixed liposomes stability, mean diameter after one freeze-thaw cycle remained unchanged for molar ratios from 10/0 to 8/2 of either DODPC/DPPC or DODPC/DPPC/Chol/SA liposomes. γ-Ray-induced polymerization of each mixed-liposome system was analyzed using kinetic treatment of polymerization. Although the rate of polymerization for either systems differed from that of DODPC liposomes, the polymerization mechanism was the same. Immiscibility between DODPC and unpolymerizable components was estimated based on the kinetic data of polymerization. Hydrophobic interactions of DPPC and/or Chol with DODPC significantly affected the conformation of DODPC, which rearranges into an easily polymerizable conformation. The rate and degree of polymerization thus increased.

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Infrared (IR) transmission and reflection-absorption spectra were measured for Langmuir-Blodgett (LB) films of surface-active azodye prepared at surface pressures of 5 and 30mNm^-1. The IR spectra showed that the molecules are preferentially arranged in the LB films with the molecular orientation dependent on the transfer pressure. The absorption peak of the trans isomer of the azodye in the ultraviolet-visible absorption spectra blue-shifted for the LB film prepared at 5mNm^-1 and red-shifted for that at 30mNm^-1. The formation of H and J aggregates of the azodye, respectively, would thus appear to occur. The orientation of the azodye molecules in the LB films is discussed.

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The rates of aerobic oxidation of polyunsaturated fatty acid methyl esters (PUFA) such as linoleate, α-linolenate, γ-linolenate, arachidonate, eicosapentaenoate and docosahexaenoate were compared in homogeneous chlorobenzene solution and Triton X-100 aqueous micelles at 37°C. The rate of disappearance of PUFA increased in homogeneous solution but decreased in aqueous micelles with an increasing number of unsaturation. Peroxyl radicals derived from highly unsaturated fatty acid methyl esters such as eicosapentaenoate and docosahexaenoate are considered to be more polar than those from linoleate because the ratio of oxygen uptake to substrate consumption increased from 1 to 3.4 with an increasing number of unsaturation. In the oxidation of a 1 : 1 mixture of linoleate and other PUFA in aqueous micelles, the rates of disappearance PUFA and linoleate, (-d [PUFA] /dt) / (-d [linoleate] /dt), increased while the total rates of disappearance of substrates, -d [linoleate+PUFA] /dt, decreased with an increasing number of unsaturation, indicating polar peroxyl radicals from highly unsaturated lipids not to propagate the chain oxidation. The rate of disappearance of butyl hydroxytoluene situated in the core of micelles decreased with an increasing number of unsaturation during the oxidation of PUFA. All of the data support the idea that polar peroxyl radicals from highly unsaturated fatty acid methyl ester migrate from the core to the micelle surface with consequent reduction in rates of oxidation by enhancing the rates of termination and reducing the rates of propagation.

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Examination was made of the phase behavior of polyglycerin fatty acid esters in a water-oil system and aggregate structure by phase study and amall angle X-ray scattering (SAXS). Polyglycerin laurate (10G^* 0.7L and 20G^* 1L) were used, 10G^* and 20G^* indicating the average polymerization degree of polyglyceryl chain as 10 and 20, respectively. Neither 10G^* 0.7L nor 20G^* 1L formed a cubic phase in water at 25°C but did so with the addition of a trace amount of decane. The cubic phase was found to be a discontinuous micellar cubic phase (I₁) with a face or body centered cubic lattice by SAXS. Micelles in I₁ were not completely spherical. The thermal stability of I₁ was improved with increase in the solubilization of decane. Maximum solubilization of m-xylene and squalane in I₁ was studied and greater solubilization of m-xylene and less solubilization of squalane compared to decane were noted. An excess oil phase was found to coexist with I₁ beyond the solubilization limit of I₁ and the oil phase could be dispersed in I₁ as emulsion droplets. The highly viscous and stable gel emulsion with oil content of 80% could be formulated.

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Trans fatty acid content of confectioneries produced in 13 countries was determined by gas-liquid chromatography/silver-ion thin-layer chromatography.
This content was highest in products from the United States (27.1%), followed by Canada (22.3%), Switzerland (18.7%) and Belgium (15.0%). In the Netherlands, Norway, Sweden and the United Kingdom, total trans fatty acid content of products ranged from 11% to 12% and 6% to 8% for Denmark, Finland and Germany. In products from Australia and Italy, the content was 3.5% and 3.1%, respectively, the latter being the lowest.
The C18 : 1 trans isomer was the major trans isomer in confectioneries, and C20 : 1 and C22 : 1 trans isomers were found in 7 brands.
Total trans fatty acid content of confectioneries was essentially the same as that in household margarines and confectioneries produced in Canada, the United States and United Kingdom. In confectioneries of Belgium, Denmark, Germany and the Netherlands, the content was higher compared to household margarines produced in other countries.

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The biodegradation of 4-nonylphenol polyethoxylate (NPE-n) nonionic surfactant through bacteria results in the formation of toxic 4-nonylphenol (NP) that has been identified as an endocrine disruptor by EPA. NP persists in nature for long periods, and consequently, new wastewater treatment should be established to ensure aquatic environmental protection.
The photodegradation of NPE-n, NP and mixture solutions at the TiO₂/water interface was investigated. The photodecomposition of NP solution and NP/NPE-n mixed solutions (each 0.1mM) in aqueous TiO₂ (100mg) suspensions under UV-irradiation (320nm<λ<387nm) was monitored. After filtering TiO₂ particles, photodegradation kinetics were examined by surface tension, UV-absorbance, CO₂ evolution, TOC, FT-IR, ¹H-NMR and GC-MS. The aggregation of TiO₂ particles (studied by dynamic light scattering) and the formation of carboxylic acid intermediates (with HPLC) were examined. Surface photocatalytic reactions of NPE-n and/or NP structures on the TiO₂ semiconductor were studied by molecular orbital (MO) simulation. Efficient adsorption of the ethoxyl group on the TiO₂ surface was initially noted, followed by cleavage of the aromatic ring and the ethoxyl moiety by direct photooxidation and attack of OH radicals. No NP formation was detected in the photodecomposition of NPE. The photomineralization of the ethoxyl moiety proceeded via formic acid, and other alkyl groups and benzene rings were converted to acetic acids. The photooxidation of hydrophobic NP material proceeded as follows : (i) adsorption of the OH moiety in NP on the TiO₂ surface, (ii) facile ring-opening cleavage of phenol and (iii) CO₂ gas evolution for mineralization of NP. The photooxidation of mixed NPE-n and NP solution could be predicted from TiO₂ photooxidation results with pure NPE-n and/or NP solutions, photocatalytic degradation is thus shown to be a promising route for wastewater treatment of surfactants.

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