The effects of conjugated linoleic acids with triacylglycerol form (TAG-CLA) and free fatty acid form (FA-CLA) on lipid mass and lipid metabolizing enzymes in the liver, and on serum metabolites was compared in Otsuka Long-Evans Tokushima fatty (OLETF) rats, which have high levels of hepatic and serum triacylglycerol (TAG) and higher serum insulin, glucose, leptin and tumor necrosis factor-alpha (TNF-α). Obese rats fed either forms of CLA significantly lowered the concentrations of TAG in the liver and serum to a similar extent, compared to the control dietary group. It was further demonstrated that both forms of CLA markedly enhanced mitochondrial carnitine palmitoyltransferase (CPT) activity, but reduced microsomal phosphatidate phosphohydrolase (PAP) activity in the liver. This suggests that the CLA-induced reduction in liver lipid mass may be attributable to increase in fatty acid β-oxidation. Both forms of CLA also lowered serum leptin levels. TAG-CLA had no significant effects on serum insulin and glucose levels, whereas FA-CLA raised the serum glucose level without affecting insulin levels. TNF-α concentrations were comparable between the groups. These results suggest that TAG-CLA and FA-CLA reduce TAG levels in the liver and serum, but have different effects on fasting serum glucose levels in OLETF obese rats.

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Conjugated linoleic acid (CLA) is known to modulate lipid and lipoprotein metabolism. We examined the effects of dietary CLA (1 and 2%) on hepatic microsomal triacylglycerol transfer protein (MTP) activity, known to be essential for the assembly/secretion of the apolipoprotein B-containing lipoproteins, and lipid concentrations of liver and plasma in OLETF obese rats. A significant reduction in hepatic MTP activity in CLA-fed rats in comparison to rats fed a linoleic acid (LA) diet was noted. Hepatic and serum triacylglycerol (TAG) concentrations were lowered in the CLA groups as compared to the control LA group. Decreased serum insulin and leptin levels were seen in the CLA groups. These results indicate that dietary CLA reduces both hepatic MTP activity and TAG content, and therefore reduces hepatic lipoprotein assembly and secretion.

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Generation of singlet oxygen in protoporphyrin IX (PpIX) solubilizing surfactant solutions irradiated with light was investigated by electron spin resonance (ESR) spectroscopy using 2,2,6,6-tetramethyl-4-piperidone hydrochloride (TMPD) as a spin label probe. The surfactants employed in this study were sodium dodecyl sulfate (SDS), dodecyltrimethylammonium bromide (DTAB), and dodecyl hexaethylene glycol ether (C₁₂EO₆). When PpIX solubilizing solutions were irradiated with light, the ESR signal of TMPD nitroxide radical was observed in SDS and DTAB solutions, whereas no ESR signal appeared in C₁₂EO₆ solutions. The ESR signal of TMPD nitroxide radical disappeared in SDS and DTAB solutions when histidine, a quencher of singlet oxygen, was added, which indicates that the ESR signal is assigned to TMPD oxidized by singlet oxygen. Taking into account the solubility of PpIX in water and the distribution of TMPD between micelle and water phases, moreover, we consider that singlet oxygen generated in SDS and DTAB micellar phase is released to water bulk phase. It was also found that ESR signal of TMPD nitroxide radical in SDS system was gradually reduced at a longer period of irradiation. These results show that DTAB system is very useful to determine singlet oxygen generated by water-insoluble photosensitizing agents in water media by ESR spectroscopy with TMPD. In addition, light irradiation ranging from 350 to 450 nm generated singlet oxygen more than that from 550 to 750 nm in DTAB solutions.

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Anacardic acids, (6-[(8Z)-8-pentadecenyl] salicylic acid (1) and 6-[(8Z,11Z)-8,11,14-pentadecatrienyl] salicylic acid (2)) were isolated from the shell oil of Indonesian cashew nut and used to synthesize glycosides via glycosidation of the carboxyl group on the benzene ring. We examined these compounds for their inhibition of the enzyme tyrosinase, their superoxide scavenging activity and their inhibition of enzyme hyaluronidase. The glucosides derived from (1) and (2) were found to inhibit tyrosinase (using L-DOPA as a substrate) activity by more than 80%. The inhibitory rates exceeded that of arbutin, a compound that is used in commercial cosmetics. As the comparison, cardanols, (3-[(8Z)-8-pentadecenyl] phenol (3) and 3-[(8Z, 11Z)-8, 11, 14-pentadecatrienyl] phenol (4)) were isolated from the cashew nut shell oil and used to synthesize glycosides that we also examined for their inhibitory activity.

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To establish a method for the effective mimicking superoxide dismutase (SOD) which accerelate scavenging of the superoxide anion radical (O₂^-·), reconstituted hemoglobins each possessing the apoprotein of hemoglobins as carriers and various metalloporphyrins as active sites were synthesized and their SOD activity was determined in each case. The hemoglobins containing iron- and manganese-protoporphyrin IX (2-4) had no significant SOD activity but did so when containing cationic iron- and manganese-porphyrins (5-7). Minimum IC₅₀ as indicator of SOD activity was 1.8. t_d as indicator of hydrogen peroxide resistance was always nearly 10 times that cationic metalloporphyrins as an SOD mimic. The reconstituted hemoglobins with cationic metalloporphyrins (5-7) are shown by the present results to be potentially capable of functioning as SOD mimics.

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Laccase, a type of polyphenoloxidase, was found to oxidize unsaturated triacylglycerol under mild reaction conditions in the presence of a simple natural mediator and mediator which is derived from a natural compound. The oxidized products were characterized by UV- and IR- spectroscopic analyses, ferric thiocyanate peroxide analysis and size exclusion chromatography. It was considered that conjugated diene peroxide units were formed in the triacylglycerol without substantial polymerization or degradation reactions of the main chain in the fatty acid residual group. As the mediator, 4-hydroxybenzoic acid, a simple natural phenol, which is secreted by white rot fungi, and the products derived from natural phenols were investigated. 4-Hydroxybenzaldehyde and methyl-4-hydroxybenzoate showed high oxidation activity comparable with synthesized mediators that have been previously reported. Trans-ferulic acid and 2,6-dimethoxyphenol that are not effective for the oxidation of anthracene showed a low oxidation activity for triacylglycerol in the present reaction system. The oxidation activity of the mediators used has some relationship to its oxidation potential. A bell-shaped curve with 4-hydroxybenzaldehyde as its apex may be drawn for the 4-substituted phenols when 4-hydroxybenzoic acid and alkyl-4-hydroxybenzoate were excluded.

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Ultrasonic waves were used to perform suspension polymerization of styrene monomer in the absence of both emulsifier (surfactant) and polymerization initiator. Styrene monomer was ultrasonically dispersed as oil droplets at 40 kHz after being added dropwise into water. Polymerization of the monomer in the droplets was initiated with the radical species from water as the polymerization initiator generated by irradiation with a high frequency ultrasonic wave at 200 kHz on the surfactant-free (styrene monomer/water) emulsion. The particles thus prepared were confirmed to be polystyrene particles by FT-IR measurements and the particle size was found to be several tens nanometers through TEM observation and dynamic light scattering measurement.

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Volatile oils were obtained from melon hairy roots produced by the infection with Agrobacterium rhizogenes, and their constituents were analyzed by GC and GC-MS spectroscopy. Characteristic major components were 1-nonanal, (Z)-6-nonenol, and (E,Z)-2,6-nonadienal. The melon hairy roots are thus shown to produce volatile components with the fragrance of ripe melon fruit.

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