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Marine Oils (marine + oil)
Selected AbstractsKINETICS OF HYDROCARBON GAS GENERATION FROM MARINE KEROGEN AND OIL: IMPLICATIONS FOR THE ORIGIN OF NATURAL GASES IN THE HETIANHE GASFIELD, TARIM BASIN, NW CHINAJOURNAL OF PETROLEUM GEOLOGY, Issue 4 2007Yunpeng Wang In this paper we derive kinetic parameters for the generation of gaseous hydrocarbons (C1-5) and methane (C1) from closed-system laboratory pyrolysis of selected samples of marine kerogen and oil from the SW Tarim Basin. The activation energy distributions for the generation of both C1-5 (Ea = 59-72kcal, A = 1.0×1014 s,1) and C1 (Ea = 61-78kcal, A = 6.06×1014 s,1) hydrocarbons from the marine oil are narrower than those for the generation of these hydrocarbons from marine kerogen (Ea = 50-74kcal, A = 1.0×1014 s,1 for C1-5; and Ea = 48-72kcal, A=3.9×1013 s,1 for C1, respectively). Using these kinetic parameters, both the yields and timings of C1-5 and C1 hydrocarbons generated from Cambrian source rocks and from in-reservoir cracking of oil in Ordovician strata were predicted for selected wells along a north-south profile in the SW of the basin. Thermodynamic conditions for the cracking of oil and kerogen were modelled within the context of the geological framework. It is suggested that marine kerogen began to crack at temperatures of around 120°C (or 0.8 %Ro) and entered the gas window at 138°C (or 1.05 %Ro); whereas the marine oil began to crack at about 140 °C (or 1.1 %Ro) and entered the gas window at 158 °C (or 1.6%Ro). The main geological controls identified for gas accumulations in the Bachu Arch (Southwest Depression, SW Tarim Basin) include the remaining gas potential following Caledonian uplift; oil trapping and preservation in basal Ordovician strata; the extent of breaching of Ordovician reservoirs; and whether reservoir burial depths are sufficiently deep for oil cracking to have occurred. In the Maigaiti Slope and Southwest Depression, the timing of gas generation was later than that in the Bachu Arch, with much higher yields and generation rates, and hence better prospects for gas exploration. It appears from the gas generation kinetics that the primary source for the gases in the Hetianhe gasfield was the Southwest Depression. [source] PETROLEUM SEEPAGES AT ASUK, DISKO, WEST GREENLAND: IMPLICATIONS FOR REGIONAL PETROLEUM EXPLORATIONJOURNAL OF PETROLEUM GEOLOGY, Issue 3 2007J. A. Bojesen-Koefoed Organic geochemical screening and biological marker analysis was carried out on a total of 45 Albian-Cenomanian sandstone and mudstone samples collected from a landslide block on thenorth coast of Disko island, central West Greenland. The landslide block covers an area of severalsquare kilometres, and originated approximately 400 m up-section from where it moved to itspresent position after the last glaciation. The mudstones are generally rich in organic carbon butshow no potential for petroleum generation. However, biodegraded oil stains were found in thepoorly lithified sandstones. Staining by undegraded or only slightly degraded oil in volcanic rocks iscommon in this region, but the occurrence described here is the only known outcrop where staining occurs in siliciclastic sediments, and also the only one known in which the oil is severely biodegraded. The oil stains appear to represent a biodegraded variety of the Cretaceous marine shale derived Itilli oil type which is known from many locations in the Disko-Nussusaq-Svartenhuk Halvø region. The oils entered the sandstones before the landslide event, probably during or beforethe extrusion of the volcanic succession in the Paleogene. This is the first time that a petroleum seepage has been found to the east of the Kuugannguaq-Qunnillik fault zone, which is located approximately 30 km west of Asuk. The presence of stainingby marine oil at Asuk demonstrates that marine petroleum source rocks were deposited muchfurther eastwards than was previously thought, thus expanding the area of potential explorationsignificantly. The presence of marine source rocks to the east of the Kuugannguaq-Qunnillik faultzone may explain the frequent observation of Direct Hydrocarbon Indicators in seismic datacollected in the Vaigat Sound. [source] Dietary intake of differently fed salmon: a preliminary study on contaminantsEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 3 2006C. Bethune Abstract Background, In a previous study, a group of coronary heart disease (CHD) patients exhibited positive cardioprotective effects of fatty acids derived from a diet of farmed Atlantic salmon fed fish oil (Seierstad et al. 2005). This follow-up study examines these patients for plasma exposure to selected organic and inorganic contaminants found in seafood that may detract from the benefits of eating oily fish. Methods, The study design was from Seierstad et al. (2005), where 58 patients were allocated into three groups consuming 700 g week,1 of differently fed Atlantic salmon (Salmo salar) fillets for 6 weeks: 100% fish oil (FO), 100% rapeseed oil (RO), or 50% of each (FO/RO). Results, Different fillets showed graded levels (FO > FO/RO > RO) of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (DLPCBs), indicator PCBs, polybrominated diphenyl ethers (PBDEs), and arsenic (As). Mercury (Hg) and lead (Pb) levels were similar across the three types of fillets. After 6 weeks of consumption, patient levels of PCDDs, DLPCBs, and PCBs in plasma decreased as the dietary intake of these contaminants increased. Plasma PBDEs only showed increases for the FO patients. Levels of inorganic contaminants in plasma showed only slight changes over the study period. Conclusions, These results show a reduction in the use of marine oils in fish feed reduces organic contaminant levels in farmed salmon while still providing a good dietary source of marine fatty acids. [source] BIOCHEMICAL CHARACTERIZATION OF BORAGE (BORAGO OFFICINALIS L.) SEEDSJOURNAL OF FOOD BIOCHEMISTRY, Issue 3 2009BAYA MHAMDI ABSTRACT Gas chromatography,mass spectrometry analysis of seed Borago officinalis essential oil (EO) revealed the presence of 16 volatile components. ,-Caryophyllene (26%) and p-cymene-8-ol (19.7%) represented the major components, while nonadecane (0.7%) and hexanol (0.7%) were the minor ones. The EO composition was characterized by higher abundance of oxygenated monoterpenes (27.7%), followed by sesquiterpenes (26%). Fatty acid composition showed the predominance of linoleic (35.4%), oleic (24.2%) and ,-linolenic (20.4%) acids. Polyphenols were analyzed by reversed-phase high-performance liquid chromatography after acid hydrolysis of phenolic acid esters. Six phenolic acids were identified in seed extract and rosmarinic acid was the predominant one with 1.65 mg/g dry matter weight equivalent to 33% of total phenolic acids. PRACTICAL APPLICATIONS Borage (Borago officinalis L.) is of great interest because of its medicinal and nutritional properties. In fact, thanks to its characteristic composition in fatty acids, particularly high levels of gamma-linolenic acid in its seed oil, borage has gained importance. The potent consumers of this medicinal plant are hypertensive and hypercholesterolemic people. Borage consumption is also recommended for people suffering from rheumatism and eczema. Unfortunately, the knowledge about antioxidative/antiradical properties of borage is very scanty. So, recently, an extensive investigation was focused on the antioxidant properties of borage extracts. These extracts showed excellent antioxidant properties and their effects were attributed to their phenolic constituents. These antioxidants can be concentrated, either as crude extracts or individual phenolic compounds, to be used in highly unsaturated oils such as marine oils. Furthermore, borage consumption has been reported as a possible gastric cancer protective factor. [source] Seizure resistance in fat-1 transgenic mice endogenously synthesizing high levels of omega-3 polyunsaturated fatty acidsJOURNAL OF NEUROCHEMISTRY, Issue 2 2008Ameer Y. Taha Abstract n-3 polyunsaturated fatty acids (PUFA), derived from marine oils, have been shown to protect against various neurological diseases. However, very little is known about their potential anticonvulsant properties. The objective of the present study was to determine whether enrichment of brain lipids with n-3 PUFA inhibits seizures induced by pentylenetetrazol. We demonstrate that increased brain levels of n-3 PUFA in transgenic fat-1 male mice, which are capable of de novo synthesis of n-3 PUFA from n-6 PUFA, increases latency to seizure onset by 45%, relative to wildtype controls (p = 0.08). Compared with wildtype littermates, transgenic fat-1 mice have significantly (p < 0.05) higher levels of docosahexaenoic acid and total n-3 PUFA in brain total lipid extracts and phospholipids. Levels of brain docosahexaenoic acid were positively correlated to seizure latency (p < 0.05). These findings demonstrate that n-3 PUFA have anticonvulsant properties and suggest the possibility of a novel, non-drug dietary approach for the treatment of epilepsy. [source] Fatty acid composition and volatile compounds of selected marine oils and mealsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2009Ioannis Giogios Abstract BACKGROUND: Although volatile compounds characterising seafood have been studied extensively, no similar data are available regarding the volatiles of raw materials used in fish feed. Therefore the aim of this study was to make an initial screening of the volatiles of various common marine raw materials used in the aquaculture feed industry. Nine commercial marine oils (German (GFO1, GFO2 and GFO3) and Norwegian (NFO) fish oils and salmon (SO1 and SO2), tuna (TO), sardine (SRDO) and shrimp (SHO) oils) and eight commercial marine meals (Peruvian (PFM1 and PFM2), Danish (DFM1 and DFM2) and prime quality (PQFM1 and PQFM2) fish meals and Antarctic krill meals (KM1 and KM2)) were analysed for their fatty acid profiles and volatile flavour compounds. The relation between fatty acids and volatiles was examined. RESULTS: The highest polyunsaturated fatty acid and eicosapentaenoic acid (20:5,3) contents and ,3/,6 ratio were found in NFO. The fatty acid composition of all marine meals except krill meals was found to be more variable among batches than that of marine oils. Regarding volatiles, all marine raw materials were characterised by the complete absence or negligible levels of eight- and nine-carbon alcohols and carbonyls. All marine oils were found to have high 2-ethyl furan, 2-methylenebutyl cyclopropane, hexanal, 2,4-octadiene and 3,5-octadiene contents. Marine meals, unlike marine oils, were characterised by the almost complete absence of unsaturated and cyclic hydrocarbons and terpenes and very low levels of furans. CONCLUSION: Volatiles of marine meals differ from those of marine oils. Unlike fatty acids which give useful traceability information, volatiles seem to fail in this role owing to their strong variability. Copyright © 2008 Society of Chemical Industry [source] Metabolic effects of ,-3 fatty acidsBIOFACTORS, Issue 1-4 2000Harald Osmundsen Some metabolic effects of dietary marine oils, or of dietary eicosapentaenoic or docosahexaenoic acid are reviewed. It is pointed out that docosahexaenoic acid appears more effective as regards induction of peroxisomal ,-oxidation. Similarly, docosahexaenoic appears more powerful in terms of suppression of hepatic ,9 -desaturase activity and mRNA-levels. The potential inhibitory effect of polyunsaturated fatty acids, particularly docosahexaenoic acid, on mitochondrial ,-oxidation is discussed. Experiments with rats suggesting that the hypolipidaemic response of eicosapentaenoic acid is more marked when the fatty acid was given to fed rats, as compared to fasted rats, are discussed. [source] | |||||||||||||