We investigated the effects of phytosterol esters on serum lipids and fecal steroids excretion. Golden Syrian Hamsters were fed diets containing 100 g of control oil, free phytosterol (FPS) oil or phytosterol ester (PSE) oil per kilogram of feed supplemented with cholesterol (2 g/kg feed), for 15 or 29 days. Each oil contained 0.36%, 3.71%, or 3.69% FPS or FPS-equivalent PSE, respectively. The serum total cholesterol concentrations in hamsters fed the FPS diet (216 ± 6 mg/dL) or the PSE diet (220 ± 5 mg/dL) were significantly lower compared with those fed the control diet (239 ± 6 mg/dL) at day 29 (p<0.05). There was no significant difference in the ratio of non-HDL-cholesterol to HDL-cholesterol in any group at the same determination point. Fecal cholesterol excretion increased in hamsters fed the FPS diet and the PSE diet compared with those fed the control diet. These results suggest that PSE effectively lowers blood cholesterol, and that there is no difference between FPS and PSE regarding their cholesterol lowering effect.

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Comparison of differences in animal species facilitates clarification of the physiological functions of sphingoglicolipids. Thus, in the present study, examination was made of the characteristics of ganglioside components in the livers of sardines. Monosialogangliosides were found to constitute 90.8% of total gangliosides. The main ingredient of the mammalian non-nervous system is GM3, but the major ganglioside present most in sardine livers was noted to be GM4 containing only N-acetylneuraminic acid, followed by GM3 and GM2. The main fatty acid component of GM4 was h 24:0 (43.3%). Hydroxy fatty acid (92.7%) and saturated fatty acid (77.9%) were significantly more compared to GM3 and GM2. Fatty acids of GM3 and GM2 were virtually the same but differed considerably from those of GM4, thus indicating differences in the metabolic pathway.

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The photocatalyzed degradation of surface-active and surface-inactive naphthalene-sulfonate derivatives has been investigated in UV-irradiated air-equilibrated heterogeneous TiO₂ dispersions. The dynamics for the photodegradation of sodium butylnaphthhalene-1-sulfonate (B-1-NS) and sodium naphthalene-1-sulfonate (1-NS) are compared to those of sodium dodecylbenzenesulfonate (DBS) and sodium benzenesulfonate (BS). The adsorption behavior of the surfactants on the TiO₂ catalyst, cleavage of the aromatic ring, mineralization to carbon dioxide, formation of sulfate ions, and the temporal changes of the surface activity (surface tension) against UV irradiation time were probed experimentally to provide inferences on the photoinitiated mechanism. The position(s) of ·OH and/or ·OOH radicals attack on the surfactant structure was inferred from theoretical considerations on the basis of molecular orbital calculations of frontier electron densities; similarly, the adsorption behavior of the surfactants on the TiO₂ catalyst surface was deduced from calculations of point charges of each of the atoms in the surfactant structure.

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The detergency of clay particles on cotton cloth was evaluated based on the Kubelka-Munk equation for reflectance and X-ray fluorescence from Al, Si and Fe in the particles prior to and after washing. In X-ray fluorescence the same detergency was observed for Al, Si and Fe. From this fact it may be said that particles were removed from cotton cloth. The order of detergency of clay particles for washing solutions was LAS/STPP>STPP>LAS>pure water. The detergency based on the Kubelka-Munk equation for reflectance closely related to that from X-ray reflectance.

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We examined the effects of the dietary docosahexaenoic acid (DHA), given as monoacylglycerol (MG), diacylglycerol (DG), triacylglycerol (TG) and ethyl ester (EE), on plasma and liver lipid profiles in rats. Male Sprague-Dawley rats were fed semi purified diets containing 10% fat with a constant polyunsaturated/monounsaturated/saturated fatty acid ratio for 1 week. One% of DHA-MG, DG, TG and EE were added to the rat’s diets as a substitute for fat. Control rats were fed a fat containing linoleic acid as a sole polyunsaturated fatty acid. The apparent absorption rates of the total fat and DHA were almost quantitative (>95%) in all groups. The plasma concentrations of total and HDL cholesterol in the four DHA-supplemented groups were significantly lower than in the control group. DHA-DG and TG were more effective for lowering plasma total cholesterol concentration than DHA-MG. Also, DHA-DG was more effective than DHA-EE. The plasma TG concentration was significantly lower only in the DHA-DG and TG groups than in the control group, while this effect was more pronounced in DHA-TG than in DHA-DG. DHA feeding increased the proportion of n-3 fatty acids accompanying a complementary decrease of arachidonic acid in liver lipid fractions. The percentages of total n-3 fatty acids were significantly higher in the DHA-TG group than in other DHA groups in liver total lipids. These results suggest that the structural differences of DHA-containing lipids in dietary fats affected lipid metabolism differently in rats, and the DHA-DG and TG more effectively reduced plasma lipids than DHA-MG and EE.

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Novel superoxide dismutase (SOD) mimics, the macromolecule-ironporphyrin possessing poly(L-lysine) (PLLN) and iron tetraphenylporphyrin derivative are synthesized and their SOD activities are evaluated. The synthesis of PLLN-bound iron nicotinoylamido-fenced tetraphenylporphyrin (PLLN/FeNFP), iron pivaloylamido-fenced tetraphenylporphyrin (PLLN/FePFP) and iron tetraphenylporphyrin (PLLN/FeP) is conducted: The molar ratio of the iron tetraphenylporphyrin derivative to the structural unit of PLLN is found to be about 1/10 under the condition of this study. The rate constant, k_cat, as indicator of SOD activity is about 10⁶ M^-1 s^-1. PLLN/FePFP is shown far more capable of functioning as a SOD mimic compared to macromolecule-ironporphyrins, owing to creation of space for an active site due to the cationic polymer domain and fenced-groups.

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Fractured reservoirs (e.g. Asmari reservoirs in Iran) provide over 20 % of the world oil reserves in our nation. Iran is one of the wold’s leading energy producing countries. Almost 90% of Iranian reservoirs are carbonate and oil production is due to natural fractures. The declining oil production from Iranian fractured reservoirs after several decades of exploitation and the significant amount of oil still remaining in place are of great concern to the Iranian oil company and fully justify its interest in EOR processes. One of the important mechanisms in EOR from fractured reservoirs is miscible fluid injection. Unfortunately, our knowledge about miscible fluid displacement in fractured porous media is limited and there is very little work in the literature on this method. Modeling of miscible displacement in fractured porous media is the subject of this study. In this modeling, mass transfer between matrix and fracture due to diffusion, and crossflow from matrix to fracture and from fracture to matrix are considered. From theoretical aspects, it is concluded that miscible injection in fractured reservoirs can be very efficient. Thus, it is proposed for increasing oil recovery from fractured reservoirs, miscible fluid injection be done in some suitable reservoirs.

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