Abstract  This paper investigated the use of Bacillus coagulans W-15 immobilized on carriers in a bio-contact oxidation reactor to treat oilfield produced water. It researched the effect of hydraulic retention time (HRT) on the removal efficiencies of chemical oxidation demand (COD) and total organic carbon (TOC). The results showed that, when the HRT was 24 and 32 h, the COD of effluent water were less than or equal to 352 mg/L, the removal efficiencies of COD and TOC were greater than or equal to 75% and 68%, respectively. The degradation efficiencies in the bio-contact oxidation reactor immobilized with W-5 were estimated to be 73% for total oil, and 86% for the gas chromatography resolved compounds. The quality of the effluent water met the professional emission standard of petrochemical industry of China.

Abstract  Predisafe (rabbit cornea broblast cells culture) is an alternative method developped by Biopredic to determine the occular irritating potential. Cell layer was exposed to pure solution of perhydrosqualen (animal squalan) and cytotoxicity was evluated by neutral red colorimetric method. The results show an ocular tolerance inferior to 15, the substance is considered as slightly irritant for eyes.

Abstract  Assessment of mutagenic activity of squalane was conduced on "Salmonella typhimurium his-" and "Escherichia coli WP2(uvrA)" strains according to the OECD guideline n°471. There is no signicant difference between the number of spontaneaous reversions, the number of reversions obtained in the positive controls (with or without metabolica cativation), and the mean of corresponding experimental historic values obtained in the laboratory. There is no evidence of any increase of number of revertant colonies in the presence of the test substance (5000, 1000, 500, 100 and 50 µg) with or without metabolic activation for bacterial strains in Salmonella typhimurium TA1535, TA97a, TA98, TA100 and Escherichia coli WP2(uvrA).

Abstract  In the present work, we focused on the aging behavior of stabilized and unstabilized polyolefins using the solvent squalane as a polypropylene-mimicking model. It was found that squalane as well as polypropylene show aging-induced photoluminescence emissions at elevated temperatures. To separate and identify the photoluminescent species from other aging-induced degradation products, a high performance liquid chromatography method using photoluminescence detection (lambda(Ex) = 375 nm, lambda(Em) = 410 nm) was developed. Comparison of the integrated photoluminescence intensities allowed performing a stabilizer efficacy rating of different squalane-antioxidant formulations. For characterization and structure elucidation of the photoluminescent degradation products, the liquid chromatogaphic method was adapted for coupling to a high resolution Orbitrap mass spectrometer. It was possible to assign the observed masses to (multiple) unsaturated carbonyl compounds, which is in accordance to previous investigations. (C) 2015 Elsevier Ltd. All rights reserved.

Abstract  The interaction of hydrocarbon chains at aqueous interfaces is a major factor in defining the interfacial structures of monolayers and membranes formed by surfactants. The intermolecular pair potentials which can be expressed in the two-dimensional second virial coefficients (B-2(T)) are basic to understanding these structures. In this report, measurements of the adsorption of hexane vapor on water as a function of the partial vapor pressure are reported for a static system in which the vapor pressure is controlled by mixing liquid hexane with either hexadecane or squalane. The B-2(T) for hexane at the water/vapor interface is approximately estimated at one temperature. The results confirm that the extensive published data on the adsorption of alkanes on water obtained in a vapor now system are incorrect, presumably due to inadequate vapor saturation.

Abstract  The heterogeneous reaction of hydroxyl radicals with chemically reduced organic aerosol comprised of either squalane or bis(2-ethylhexyl) sebacate are used as model systems to examine how cloud condensation nuclei (CCN) activity evolves with photochemical oxidation. Over the course of the reaction, the critical super-saturation evolves both by the formation of new oxygen functional groups and by changes in aerosol size through the formation of gas phase reaction products. A statistical model of the heterogeneous reaction reveals that it is the formation, volatilization, solubility, and surface activity of many generations of oxidation products that together control the average changes in aerosol hygroscopicity. The experimental observations and model demonstrate the importance of considering the underlying population or subpopulation of species within a particle and how they each uniquely contribute to the average hygroscopicity of a multi-component aerosol. To accurately predict changes in CCN activity upon oxidation requires a reduction in the surface tension of the activating droplet by a subpopulation of squalane reaction products. These results provide additional evidence that surface tension-concentration parameterizations based on macroscopic data should be modified for microscopic droplets.

Abstract  On the basis of ongoing research conducted on the clarification of processes responsible for lubricant degradation in the environment of piston grooves in exhaust gas recirculation (EGR) diesel engines, an experimental investigation was aimed to develop a kinetic model, which can be used for the prediction of lubricant oxidative degradation correlated with endurance test conducted on engines. Knowing that base oils are a complex blend of paraffins and naphthenes with a wide range of sizes and structures, their chemistry analysis during the oxidation process can be highly convoluted. In the present work, investigations were carried out with the squalane (C30H62) chosen for its physical and chemical similarities with the lubricant base oils used during the investigations. Thermo-oxidative degradation of this hydrocarbon was conducted at atmospheric pressure in a tubular furnace, while varying temperature and duration of the tests in order to establish an oxidation reaction rate law. The same experimental procedures were applied to squalane doped with two different phenolic antioxidants usually present in engine oil composition: 2,6-di-tert-butyl-4-methylphenol and octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate. Thus, the effect of both antioxidants on the oxidation rate law was investigated. Data analysis of the oxidized samples (Fourier transform infrared spectroscopy and gas chromatography/mass spectrometry) allowed rationalization of the thermo-oxidative degradation of squalane. The resulting kinetic modeling provides a practical analytical tool to follow the thermal degradation processes, which can be used for prediction of base oil hydrocarbon aging. If experiments confirmed the role of phenolic additives as an effective agent to lower oxidation rates, the main results lie in the observation of a threshold temperature where a reversed activity of these additives was observed. [DOI: 10.1115/1.3155797]

Abstract  We performed the rabbit skin closed patch tests about the sefety evaluation method of cosmetic ingredients. Test materials include propylene glycol, 1, 3-butylene glycol, glycerin, liquid paraffin, squalane and pristane. This study was performed in three cosmetic companies. The results were as follows. (1) Clear positive reactions were seen only with propylene glycol and pristane. (2) Among the three polyols tested, the score of propylene glycol was the highest in primary irritant.There is no difference between 1, 3-butylene glycol and glycerin, and they showed only weak reactions. Pristane was a strong irritant as expected, but liquid paraffin and squalane showed only weak reactions. (3) As to propylene glycol, strong reactins were seen only with 100% but not with 30% and 10 concentrations. (4) Average score of each materials was different, but the order of irritant was the same in three lavoratories.

Abstract  The reaction of Cl atoms, in the presence of Cl(2) and O(2), with sub-micron squalane particles is used as a model system to explore how surface hydrogen abstraction reactions initiate chain reactions that rapidly transform the chemical composition of an organic particle. The heterogeneous reaction is measured in a photochemical flow tube reactor in which chlorine atoms are produced by the photolysis of Cl(2) at 365 nm. By monitoring the heterogeneous reaction, using a vacuum ultraviolet photoionization aerosol mass spectrometer, the effective reactive uptake coefficient and the distributions of both oxygenated and chlorinated reaction products are measured and found to depend sensitively upon O(2), Cl(2), and Cl concentrations in the flow reactor. In the absence of O(2), the effective reactive uptake coefficient monotonically increases with Cl(2) concentration to a value of ∼3, clearly indicating the presence of secondary chain chemistry occurring in the condensed phase. The effective uptake coefficient decreases with increasing O(2) approaching a diffusion corrected value of 0.65 ± 0.07, when 20% of the total nitrogen flow rate in the reactor is replaced with O(2). Using a kinetic model it is found that the amount of secondary chemistry and the product distributions in the aerosol phase are controlled by the competitive reaction rates of O(2) and Cl(2) with alkyl radicals. The role that a heterogeneous pathway might play in the reaction of alkyl radicals with O(2) and Cl(2) is investigated within a reasonable range of reaction parameters. These results show, more generally, that for heterogeneous reactions involving secondary chain chemistry, time and radical concentration are not interchangeable kinetic quantities, but rather the observed reaction rate and product formation chemistry depends sensitively upon the concentrations and time evolution of radical initiators and those species that propagate or terminate free radical chain reactions.

Abstract  BIOSIS COPYRIGHT: BIOL ABS. RRM HEXAMETHYLTETRACOSAN METABOLIC-DRUG ANTIDOTE-DRUG POLYCHLOROBIPHENYL POLYCHLORODIBENZOFURAN 3 METHYLCHOLANTHRENE TYPE TOXICITY FOOD CONSUMPTION GROWTH LIVER ENLARGEMENT THYMUS ATROPHY YUSHO RICE OIL

Abstract  The adsorption of the phospholipid (PL) 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) dissolved in the oil phase squalene or squalane was studied at the interface with water. Dynamic interfacial tension was measured by profile analysis tensiometry (PAT). Two different setups were considered, a buoyant oil drop surrounded by water or a pendant water drop in oil. For the proof of methodology the interfacial tensions of water in chloroform and chloroform in water interfaces were measured. From the equilibrium interfacial tensions of different PL concentrations, the Gibbs adsorption isotherm was determined. These isotherms allow the extraction of the minimal areas per lipid molecule as well as critical aggregation concentration (CAC). We found significant differences in the results obtained for both setups. By means of PAT, the CAC determined for water drops in oil was smaller than for oil drops in water. Photon correlation spectroscopy (PCS) and nuclear magnetic resonance (NMR) were used to verify the determined CACs. We concluded the setup-dependent differences to be caused by depletion effects when initially dissolving the surface active component in the small drop volume. We recommend the reversed setup where the surface active component is dissolved in the surrounding bulk phase to avoid corrections of bulk concentrations. (C) 2015 Elsevier B.V. All rights reserved.

Abstract  Tetradecane (TD), testosterone (TS), and dimethyl sulfoxide (DMSO) were separately inuncted on rabbit pinnas once a day; the pinnas were biopsied on days 1, 3, 7, and 28. Untreated pinnas and squalane-treated pinnas were used as controls. Three-dimensional images of sebaceous glands were reconstructed from their serial histologic sections using a computer-image analysis system. By stereometry, the sebaceous gland volumes gradually increased during the course of treatments with TS and DMSO, whereas the volumes of TD-treated sebaceous glands increased, reached the maximum on day 7, and then decreased. The acinus number was increased by all the substances, the DMSO-treated sebaceous glands on day 28 showing the largest number of acini. The volumes of individual acini increased until day 28 with TS treatment, whereas with TD and DMSO treatments they increased, reached the maximum on day 7, and then decreased. Stereographically, each untreated control sebaceous gland was composed of 20-30 pear-shaped acini. On day 28, acini of TS-treated sebaceous glands were swollen and ovoid in shape, DMSO-treated sebaceous glands resembled a bunch of grapes, and acini of TD-treated sebaceous glands were widely scattered and showed globular swelling arising from an elongated tube. Hyperplastic responses of sebaceous glands are quite different according to substances applied topically.

Abstract  This study investigated the removal of long-chain alkanes, which are released as the result of shipping activities and fuel oil spills, with Penicillium simplicissimum YK, a fungus that degrades polyethylene. Two branched alkanes (pristane and squalane) and a phosphoric ester (Plysurf A210G) were used separately as a dispersant. Yeast extract and malt extract were added as a supplementary nutrient, respectively, to enhance cell growth. Squalane was found to be more favorable to the long-chain n-alkane degradation than pristine when the cell density was higher. When 0.001% (w/v) Plysurf A210G was used as the dispersant and 0.3% malt extract was added as the supplementary nutrient, about 26% to 51% of an initial concentration of 0.10% (w/v) of n-alkanes 30 to 40 carbons long was degraded in two weeks. In this case, no apparent correlation was observed between the molecular weights of the long-chain n-alkanes and their degradation rates. In a separate experiment, it was confirmed that the fungus used pristane, squalane, and n-alkanes with a chain of 20 and 50 carbons long for growth. This report demonstrated the biodegradability of the long-chain straight and branched alkanes by Penicillium simplicissimum YK.

Abstract  Alkanes having unusual saturated isoprenoidal and methyl-branched structures have been isolated from the bitumen of several sediments. The methanogenic biomarkers 2,6,10,15,19-pentamethyleicosane and squalane were found in sediments which also contained bacteriogenic glycerol ethers. However, in one ether-containing sediment, 2,6,10,13,17,21 -hexamethyldocosane was tentatively identified and this compound was found in place of the established alkane biomarkers. Other hydrocarbons found were regular C21 and C23 isoprenoid alkanes, compounds which cannot be derived from phytol; two isoprenoids of the type 3,7,11 . . . -polymethylalkane, previously reported only in petroleums; 8-methylheptadecane, a probable biomarker for cyanobacteria and a number of its homologs and other methyl-branched alkanes. Ubiquitous branched-chain alkylbenzenes and a homology of trimethylalkylbenzenes were also isolated. Most, or all, of the compounds reported here are probably not catagenetic products but may represent direct algal or bacterial bioinputs.

Abstract  In this study, the molecular composition and biomarker distribution of lacustrine sediments from Val-1 drillhole in the central zone of the western part of the Valjevo-Mionica basin were investigated at depth interval of 0- 400 m. Former investigations have shown that the core material can be separated into six depth intervals based on bulk geochemical, mineralogical and sedimentological characteristics. Concerning the quality of organic matter, presence of specific minerals, and high salinity and anoxicity, or alkalinity, three zones are of highest interest, defined at depth intervals of 15-75 m (A), 75-200 m (B) and 360-400 m (F). The first aim of the study was to identify which biomarkers characterize these specific intervals. The second aim, addressing the transitions zones of these intervals, was to extend the changes in the characteristics of the organic substance, to reflect the changes of conditions in the depositional environment as well as to define biomarker parameters which are the most sensitive sedimentological indicators. The sediments from the hypersaline anoxic and alkaline environment show high contribution of algal precursor biomass, what is in accordance with the good quality of organic substances in the sediments from these zones. High squalane content and low content of regular isoprenoid C sub(25) are typical for hypersaline anoxic environment, whereas sediments from alkaline environment have high regular isoprenoid C sub(25) content. Transition to specific sedimentation zones is characterized by change in total organic matter content, and of both free and pyrolysis-derived, and change in hydrogen index value. In the biomarker distributions, more significant changes were detected in distributions of n-alkanes and isoprenoids, compared to polycyclic alkanes. The most intensive changes in alkane distribution are reflected in changes in n-C sub(17) content compared to n-C sub(27), and phytane compared to n-C sub(18). In addition, significant sensitivity was seen in ratios between squalane and n-alkane C sub(26) (hypersaline depositional environment), or isoprenoid C sub(25) and n-alkane C sub(22) for high alkalinity environment. This study showed that Sq/n-C sub(26) ratio can be used to assess the quality of organic substance in immature lacustrine sediments.

Abstract  Adjuvants can be used with recombinant antigens to elicit cell-mediated immunity and antibodies of protective isotypes (IgG2a in the mouse and IgG1 in primates). Adjuvants should not produce reactions at injection sites, be pyrogenic or induce anterior uveitis or arthritis. Among 130 analogs of muramyl dipeptides tested, N-acetylmuramyl-L-threonyl-D-isoglutamine showed the greatest separation of potency as an adjuvant from potency in the production of side-effects. A stable emulsion of squalane and the Pluronic polymer L-121 provides a versatile vehicle for targeting of antigens to antigen-presenting cells. The combination of this emulsion with the threonyl analog of MDP is termed Syntex Adjuvant Formulation. This formulation increases the efficacy of influenza, hepatitis B virus, herpes simplex virus, lentivirus and tumor vaccines in experimental animals.