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At least 595 records · Page 33Linked to original sources
PubMed1995

Establishment of oil-degrading bacteria associated with cyanobacteria in oil-polluted soil.

A unique natural microbial cocktail with promising potential for remediating oil-polluted desert in the Gulf region is reported. Oil-degrading micro-organisms immobilized within dense cyanobacterial mats on oily coasts of the Arabian Gulf were successfully established in oil-contaminated sand. Those micro-organisms biodegraded 50% of the oil within 10-20 weeks. Nocardioforms belonging to the genus Rhodococcus predominated in the first few weeks, but after 22 weeks Pseudomonas spp. increased, sharing Rhodococcus in the predominance. Other oil-utilizing bacterial genera included Bacillus and Arthrobacter. Filamentous actinomycetes belonging to the genera Streptomyces and probably Thermoactinomyces, as well as fungi belonging mainly to Aspergillus and Penicillium increased in the contaminated sand during the experiment but declined later. Representative strains grew on spectra of the tested n-alkanes with chain lengths between C10 and C40, as sole sources of carbon and energy.

Alkanes↗
PubMed2004

Crude-oil-degrading thermophilic bacterium isolated from an oil field.

Thermophilic bacterium strain C2, which has the ability to transform crude oils, was isolated from the reservoir of the Shengli oil field in East China. The Gram-negative, rod-shaped, nonmotile cells were grown at a high temperature, up to 83 degrees C, in the neutral to alkaline pH range. Depending on the culture conditions, the organism occurred as single rods or as filamentous aggregates. Strain C2 was grown chemoorganotrophically and produced metabolites, such as volatile fatty acids, 1,2-benzenedicarboxylic acid, bis(2-ethylhexyl)ester, dibutyl phthalate, and di-n-octyl phthalate. It could metabolize different organic substrates (acetate, D-glucose, fructose, glycerol, maltose, pyruvate, starch, sucrose, xylose, hexadecane). The G+C content (68 mol%) and the 16S rRNA sequence of strain C2 indicated that the isolate belonged to the genus Thermus. The strain affected different crude oils and changed their physical and chemical properties. The biochemical interactions between crude oils and strain C2 follow distinct trends characterized by a group of chemical markers (saturates, aromatics, resins, asphaltenes). Those trends show an increase in saturates and a decrease in aromatics, resins, and asphaltenes. The bioconversion of crude oils leads to an enrichment in lighter hydrocarbons and an overall redistribution of these hydrocarbons.

Alkanes↗
PubMed1991

Investigating oiled birds from oil field waste pits.

Procedures and results of investigations concerning the oiling of inland raptors, migratory water-fowl and other birds are presented. Freon washings from the oiled birds and oil from the pits were analyzed by gas chromatography. In most instances the source of the oil could be established by chromatographic procedures. The numbers of birds involved (including many on the endangered species list) suggested the need for netting or closing oil field waste pits and mud disposal pits. Maintaining a proper chain of custody was important.

Animals↗
PubMed1992

Decrease of erythrocyte deformability in cyclosporine-treated renal transplant patients: correction with fish oil as well as corn oil.

Twenty-nine renal transplant recipients with good, stable transplant function were included in a double-blind cross-over study to investigate the effects of different immunosuppressive treatment modalities and also the effects of fish oil and corn oil supplementation on erythrocyte deformability. Ten patients were treated with cyclosporine (CyA) only, 10 patients with CyA and prednisolone, and 9 patients with azathioprine and prednisolone. Erythrocyte deformability, as measured by an ektacytometric technique, was significantly decreased in both CyA-treated groups compared with the azathioprine-prednisolone-treated group, and this decrease was corrected with fish oil and with corn oil. The cause and the clinical significance of less deformable erythrocytes due to CyA are not yet clear. However, less deformable erythrocytes could play a role in the genesis of the complications of CyA.

Adult↗
PubMed1992

Application of polyuronides for removing heavy metals from vegetable oils. III. Application of alginic acid, pectic and pectinic acids for demetalization of hydrogenated sunflower oil.

Laboratory experiments have been carried out for the removal of heavy metals from hydrogenated vegetable oils using hydrated polyuronides (degree of swelling from 4 to 12.8 ml/g) such as alginic acid, pectic and pectinic acids. The effect of the type of polyuronide, degree of esterification and oil treatment on the degree of demetalization has been studied. It has been shown that with increase in the degree of esterification of the polyuronide the efficiency of demetalization decreases. The second and third treatment of the hydrogenated oil with pectinic acid resulted in a high degree of heavy metal removal. The possibility of efficient demetalization of hydrogenated oils by treatment with water solutions of pectinic acids has also been demonstrated. The degree of metal ion removal increases with decreasing concentration of pectinic acids in the water solution.

Adsorption↗
PubMed1994

Determination of organophosphorus insecticides in edible oils and fats by splitless injection of the oil into a gas chromatograph (injector-internal headspace analysis).

Direct injection of oil or fat into a moderately heated injector enables performance of a kind of headspace technique in the injector: oil or fat is diluted 1:1 with acetone and injected into a vaporizing chamber at 200 degrees C. Components, for example organophosphorus insecticides, evaporate from the oil film on the insert wall and are transferred into the column in the splitless mode; the oil slowly flows along the wall to the bottom of the insert and is retained there in a kind of a bag. Using a flame photometric detector, detection limits are below 10 micrograms/kg.

Chromatography, Gas↗
PubMed1989

[Contaminating substances in 22 over-the-counter fish oil and cod liver oil preparations: cholesterol, heavy metals and vitamin A].

Fish oil capsules are increasingly used by self-medicating patients. We studied 22 commercial fish oil and menhaden oil preparations in respect to accompanying substances that could be harmful. The substances measured were: cholesterol as determined by gas liquid chromatography, heavy metals measured by atomic absorption, and vitamin A as determined by high-performance liquid chromatography (HPLC). The contents of cholesterol and heavy metals were in ranges which can be regarded as negligible; the content of vitamin A in menhaden oils, however, was found in amounts which warrant that pregnant women do not exceed the dosage as recommended by the manufacturers.

Animals↗
PubMed2002

Effects of dietary lipids on daunomycin-induced nephropathy in mice: comparison between cod liver oil and soybean oil.

Although it is well known that dietary lipids affect the course of glomerulonephritis in rats and humans, the precise mechanisms involved have not been fully elucidated. The aim of this study was to investigate the effects of different types of dietary lipids (fish oil and vegetable oil) on daunomycin (DM)-induced nephropathy in mice fed on soybean oil (SO) or cod liver oil (CLO). Urinary protein excretion, serum albumin, creatinine, total cholesterol, and TG were measured, and glomerular histological changes were evaluated. Antioxidant enzymes were also measured, along with the levels of lipid peroxide, GSH, thromboxane (Tx) B2, and 6-keto prostaglandin F1alpha in renal cortical tissue. Dietary CLO significantly reduced urinary albumin excretion and ameliorated the histological changes induced by DM. The increase of tissue lipid peroxide levels seen in SO-fed mice was suppressed in CLO-fed mice, whereas CLO-fed mice showed higher GSH levels than SO-fed mice throughout the experiment. In addition, renal tissue GSH peroxidase activity was significantly higher at 72 h after DM injection in CLO-DM mice than in SO-DM mice. Both renal cortical TxB2 and 6-keto PGF1alpha levels were significantly lower in CLO-DM mice than in SO-DM mice. These results suggest that inhibition of oxidative damage by dietary CLO played an important role in the prevention of DM nephropathy in this mouse model. The effect of CLO was closely associated with the inhibition of Tx synthesis.

Albuminuria↗
PubMed1987

The influence of dietary marine oil (Polepa) and evening primrose oil (Efamol) on prostaglandin production by the rat mesenteric vasculature.

The interactions of n-6 and n-3 fatty acids on prostaglandin metabolism in the isolated rat mesenteric vessels were studied. Sprague-Dawley rats (200-220 g) were fed for two weeks a fat-free semi-synthetic diet supplemented with 10% by weight of different combinations of Evening Primrose Oil (Efamol), a rich source of linoleic acid (LA) and gamma-linolenic acid (GLA), the immediate precursor of dihomo-gamma-linolenic acid (DGLA), and Polepa (POL), a marine oil rich in eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids. The combinations of supplement were as follows: 9% Efamol - 1% POL, 8% Efamol - 2% POL, 7% Efamol - 3% POL, 6% Efamol - 4% POL, 5% Efamol - 5% POL. The outflow of thromboxane (TxB2), prostacyclin (6-keto-PGF1 alpha), PGE2, and PGE1 was decreased in relation to the proportion of marine oil in the diet, except for the group which received 8% Efamol - 2% POL, and which showed an increase in 6-keto-PGF1 alpha, PGE2, and PGE1. The decrease in TxB2 was much greater than those of 6-keto-PGF1 alpha or PGE2, while PGE1 followed the same pattern as prostacyclin and PGE2. These results suggest that n-3 fatty acids, at high concentrations, inhibits conversion of both DGLA and AA to eicosanoids. Low concentrations of fish oil may, in contrast, increase formation of desirable 1 and 2 series eicosanoids.

Administration, Oral↗
PubMed2005

Toxic oil syndrome: genetic restriction and immunomodulatory effects due to adulterated oils in a model of HLA transgenic mice.

Toxic oil syndrome (TOS) was described in Spain in 1981, due to the ingestion of contaminated rapeseed oil denatured with 2% aniline. More than 20,000 persons were affected, causing over 2500 deaths. Immunological findings were: eosinophilia, mRNA for Th2 cytokines (IL-4 and IL-5) in lungs, elevated total IgE and sIL-2R and increase of DR2 HLA class II phenotypic frequency in patients died by TOS. Our objective is to test the genetic restriction found in humans using HLA transgenic mice. Results show that mice expressing human DR2 and DQ6 (both in linkage disequilibrium), had higher percentage of eosinophils (DQ6) and IgE (DR2) than other transgenic mice tested (DR3 and DR4). Also, a Th2 shift was found in DR2 transgenic mice when toxic oil was administered with OVA. This has been corroborated by the IL-5 mRNA expression in 4 out of 6 lung tissues from TOS oil treated BALB/c mice. These data indicate that an immunological response was induced as consequence of the toxic administration. These results correlate with those found in TOS patients and reinforce the implication of genetic restrictions in the acquisition of toxic-mediated disease.

Aniline Compounds↗
PubMed1996

Susceptibility of transient and commensal skin flora to the essential oil of Melaleuca alternifolia (tea tree oil).

OBJECTIVES: The purpose of this study was to determine the susceptibility of a range of transient and commensal skin flora to the essential oil of Melaleuca alternifolia, or tea tree. METHODS: A modified broth microdilution method was used. Polyoxyethylene sorbitan mono-oleate detergent was added to the test medium to enhance solubility of the tea tree oil. RESULTS: Serratia marcescens had the lowest minimum inhibitory concentration (MIC90) of 0.25%. The highest MIC90 was 3% for Pseudomonas aeruginosa. The lowest minimum bactericidal concentration (MBC90) was 0.25% for S. marcescens and Klebsiella pneumoniae, whereas the highest was 8% for Staphylococcus capitis. CONCLUSIONS: S. aureus and most of the gram-negative bacteria tested were more susceptible to tea tree oil than the coagulase-negative staphylococci and micrococci. These results suggest that tea tree oil may be useful in removing transient skin flora while suppressing but maintaining resident flora.

Gram-Negative Bacteria↗
PubMed2002

Partition behavior of virgin olive oil phenolic compounds in oil-brine mixtures during thermal processing for fish canning.

The chemical modifications and partitioning toward the brine phase (5% salt) of major phenol compounds of extra virgin olive oil (EVOO) were studied in a model system formed by sealed cans filled with oil-brine mixtures (5:1, v/v) simulating canned-in-oil food systems. Filled cans were processed in an industrial plant using two sterilization conditions commonly used during fish canning. The partitioning of phenolic compounds toward brine induced by thermal processing was studied by reversed-phase high-performance liquid chromatographic analysis of the phenol fraction extracted from oils and brine. Hydroxytyrosol (1), tyrosol (2), and the complex phenolic compounds containing 1 and 2 (i.e., the dialdehydic form of decarboxymethyl oleuropein aglycon 3, the dialdehydic form of decarboxymethyl ligstroside aglycon 4, and the oleuropein aglycon 6) decreased in the oily phase after sterilization with a marked partitioning toward the brine phase. The increase of the total amount of 1 and 2 after processing, as well as the presence of elenolic acid 7 released in brine, revealed the hydrolysis of the ester bond of hydrolyzable phenolic compounds 3, 4, and 6 during thermal processing. Both phenomena (partitioning toward the water phase and hydrolysis) contribute to explain the loss of phenolic compounds exhibited by EVOO used as filling medium in canned foods, as well as the protection of n-3 polyunsaturated fatty acids in canned-in-EVOO fish products.

Chemical Phenomena↗
PubMed2003

Solid-phase microextraction in the analysis of virgin olive oil volatile fraction: characterization of virgin olive oils from two distinct geographical areas of northern Italy.

SPME was employed to characterize the volatile profile of virgin olive oils produced in two geographical areas of northern Italy: the region of the Gulf of Trieste and the area near Lake Garda. There are as yet no data on the headspace composition of virgin olive oils from these regions, characterized by particular conditions of growth for Olea europaea. Using the SPME technique coupled to GC-MS and GC-FID, the volatile components of 42 industrially produced virgin olive oil samples were identified and the principal compounds quantitatively analyzed. Significant differences in the proportion of volatile constituents from oils of different varieties and geographical origins were detected. The results suggest that besides the genetic factor, environmental conditions influence the volatile formation.

Chromatography, Gas↗
PubMed2004

Kinetics of diglyceride formation and isomerization in virgin olive oils by employing 31P NMR spectroscopy. Formulation of a quantitative measure to assess olive oil storage history.

Diacylglycerol isomers and free acidity were determined for five extra virgin olive oils of different initial acidities by employing a facile (31)P NMR methodology as a function of storage time and storage conditions. The kinetic treatment of the hydrolysis of triacylglycerols (TGs) and the isomerization of 1,2-diacylglycerols (1,2-DGs) to 1,3-diacylglycerols (1,3-DGs) during storage of 18 months at ambient temperature in the dark and light and at 5 degrees C in the dark showed that the isomerization is strongly dependent on the rate of the TGs hydrolysis, the initial free acidity (H(0)) of the virgin olive oil samples, and storage conditions. Although the time-evolution of the diacylglycerols (DGs) depends on the TGs hydrolysis, the ratio D of the concentration of 1,2-DGs to the total amount of DGs was found to be independent of this factor. From the kinetic expression of the ratio D, a quantitative measure was formulated that allows the estimation of the storage time or age of virgin olive oils. Application of this quantitative measure to several olive oil samples of known and unknown storage history resulted in a very good agreement with respect to the actual storage time for up to 10-12 months of storage. For a longer storage period, where the isomerization of DGs is close to its equilibrium state, the calculated age index is only indicative.

Diglycerides↗
PubMed2000

Comparison of maritime pine oil and fish oil effects on plasma lipoproteins in apolipoprotein E-deficient mice.

The goal of this study was to compare the lipid lowering properties of maritime pine and fish oils in apolipoprotein E-deficient (KOE) mice, an animal model of hyperlipidemia. KOE mice were supplemented with either lard, fish or maritime pine oil (10% w/w) for one month. Compared to lard, fish and maritime pine oils decreased cholesterol (-31% and -52% respectively) and phospholipid (-41 and -52%) levels and increased triglyceride (+182% and +123%) levels. These lipid changes resulted in an enrichment in triglycerides and a depletion in cholesterol of VLDL+IDL plasma fraction as compared to lard-fed mice. These findings suggest that VLDL-triglyceride lipolysis is impaired in KOE mice fed fish or maritime pine oil.

Animals↗
PubMed1999

Extra-virgin olive oil increases the resistance of LDL to oxidation more than refined olive oil in free-living men with peripheral vascular disease.

Patients with peripheral vascular disease (Fontaine stage II) are characterized by ischemia of the lower extremities, atherosclerosis and alteration of blood coagulation and fibrinolysis. A randomized, two-period, crossover design was used to compare the effects of extra-virgin (VO) and refined olive (RO) oils on plasma lipids and lipoprotein composition and LDL oxidation susceptibility in free-living men with peripheral vascular disease. The oils differed in their antioxidant profile (alpha-tocopherol: 300 vs. 200 mg/kg; phenolic compounds 800 vs. 60) and concentration but not in their fatty acid composition. Subjects were randomly assigned to two groups. The first group (n = 12) received VO with which to freely cook all meals for 3 mo, followed by a 3-mo wash-out period; they then received RO for the final 3 mo. The second group (n = 12) consumed the oils in the opposite order. Energy, fat, polyunsaturated fatty acids (PUFA) and alpha-tocopherol intakes were not different when patients consumed the two oils. Profiles of the major fatty acids in plasma and LDL were not different after consumption of VO and RO. The slope of the line for LDL oxidation vs. the line for copper concentration was significantly higher after the intake of RO than after the intake of VO. Total LDL taken up by macrophages was significantly greater when the men consumed RO rather than VO. We suggest that antioxidants present in VO may protect LDL against oxidation more than does RO in men with peripheral vascular disease.

Aged↗
PubMed1990

The role of fish oil in psoriasis. A randomized, double-blind, placebo-controlled study to evaluate the effect of fish oil and topical corticosteroid therapy in psoriasis.

In a randomized, double-blind, placebo-controlled study, patients received 10 fish or olive oil capsules three times daily for the whole study in addition to applying betamethasone diproprionate to their psoriatic plaques for the first 3 weeks. Most patients gradually worsened upon discontinuation of corticosteroids. Using survival analysis methods, no significant difference was found between the fish and olive oil groups. The authors attempt to put the role of fish oil in the therapy of psoriasis into perspective and discuss the efficacy of fish oil when used alone versus in combination therapy.

Adult↗
PubMedDate not supplied

Effects of soybean oil and fish oil emulsions on glucose and lipid metabolism in streptozotocin-induced diabetic rats receiving total parenteral nutrition.

BACKGROUND: This study was designed to investigate the effects of fat emulsions with different fatty acid composition on plasma glucose and lipid metabolism in diabetic rats receiving total parenteral nutrition (TPN). METHODS: Diabetes was induced in rats with streptozotocin (STZ), and the rats were fed rat chow ad libitum for 6 weeks to achieve a chronic diabetic state. Control and diabetic rats were each divided into two TPN groups. The basal solutions of the two TPN groups were isonitrogenous and identical in nutrients composition except for the fat emulsion, which was made of soybean oil (SO) or fish oil (FO). The TPN control rats (C-SO and C-FO) and diabetic rats (DM-SO and DM-FO) received solutions with 37.5% of the non-protein energy provided as fat at an energy level of 30 kcal/100 g body wt/d. RESULTS: The results demonstrated that hyperglycemia and hypertriglyceridemia were induced by STZ in diabetic rats. There was no change in plasma glucose and insulin concentrations before and after TPN infusion in the TPN control groups, whereas plasma glucose as well as triglyceride (TG) and nonesterified fatty acid (NEFA) levels decreased significantly after TPN administration in the diabetic groups. No difference in the concentrations of plasma glucose, TGs, NEFAs, and insulin were observed between the two diabetic groups. CONCLUSIONS: These results suggest that compared with soybean oil, TPN with fish oil emulsion did not lead to lower plasma concentrations of TGs and NEFAs in STZ-induced diabetic rats. Also, no difference in plasma glucose and insulin levels between the two groups was observed.

Animals↗