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PubMed1998

Poor digestibility of fully hydrogenated soybean oil in rats: a potential benefit of hydrogenated fats and oils.

The digestibility and absorption of dietary triacylglycerols are dependent on a number of factors including their fatty acid profile. Data demonstrating poor bioavailability of dietary stearic acid would suggest that hydrogenated oil sources would have lower digestibility coefficients compared with their native oils. To test this hypothesis, postweanling rats were fed one of four diets, formulated to contain 40% of energy as fat (assuming complete bioavailability), for 14 d. The diets only differed by fat type, containing soybean oil (SBO), fully hydrogenated soybean oil (HSB), medium-chain triglyceride oil (MCT), or hydrogenated coconut oil (HCO). Rats fed HSB consumed more food during the last 6 d (155.2 +/- 2.7 g) than those in each of the other groups (MCT: 118.9 +/- 2. 2 g; HCO: 124.7 +/- 3.2 g; SBO: 123.8 +/- 2.3 g), yet, they did not gain more weight. Two-day fecal excretion was almost three times greater in HSB-fed rats than in rats fed any other diet (P < 0.0001) because HSB was very poorly available. The digestibility coefficients (a measure of bioavailability) of the four fats were: HSB (30.9 +/- 1.3%) < HCO (94.5 +/- 0.4%) < SBO (97.0 +/- 0.4%) < MCT (98.7 +/- 0.2%) (P < 0.0007). All rats compensated for the incomplete availability of the fats, as apparent absorbable energy consumed did not differ among diet groups. The present data suggest that HSB only contributes 11.6 kJ/g (most fats contribute approximately 37.7 kJ/g) and that not only manufactured fat substitutes, such as olestra, but also more conventional fats are incompletely available to the body. Foods that currently contain HSB may contribute much less utilizable fat and energy than presently realized.

Animal Nutritional Physiological Phenomena↗
PubMed1993

The effects of olive oil, hydrogenated palm oil, and omega-3 fatty acid-enriched diets on megakaryocytes and platelets.

Unsaturated fatty acids are thought to prevent thrombotic and arteriosclerotic disease, whereas saturated fatty acids are thought to increase the incidence of these disorders. However, the effects of these diets on megakaryocytes and platelets are not well understood. We compared the effects of diets enriched with 8.4% olive oil, 8.4% hydrogenated palm oil, or 10.2% omega-3 fatty acid ethyl esters on guinea pig megakaryocytes and platelets. In plasma, changes in fatty acid composition reflected the composition of each diet. However, in platelets and megakaryocytes, hydrogenated palm oil induced a decrease in 16:0 and an increase in 18:2 while the olive oil diet caused a marked increase in 18:1 and a decrease in most other fatty acids. The differences in the effects of the diets on cellular versus plasma fatty acids suggest that megakaryocytes and platelets have an extensive capacity to regulate their fatty acid composition. Thrombocytosis occurred with the omega-3 fatty acid-enriched diet: 12.9 +/- 1.78 x 10(5) compared with 7.45 +/- 1.08 x 10(5) platelets per microliter of platelet-rich plasma in control animals. There was an increase in megakaryocyte size, ploidy, and morphological stage (cytoplasmic maturation) with the omega-3 fatty acid-enriched diet but not with the other diets. The omega-3 fatty acid-enriched diet decreased platelet thromboxane production while the other diets had no effect. Platelet hypersensitivity was suggested in collagen aggregation studies with olive oil but not with the hydrogenated palm oil diet. Although saturated fatty acid diets are thought to be atherogenic, this diet had no affect on platelet function.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2000

Superiority of dietary safflower oil over olive oil in lowering serum cholesterol and increasing hepatic mRnas for the LDL receptor and cholesterol 7alpha-hydroxylase in exogenously hypercholesterolemic (exHC) rats.

The exogenously hypercholesterolemic (ExHC) rat is a strain segregated from SD rats with a high response to dietary cholesterol. To understand the underlying mechanism(s) for this hypercholesterolemia, the interactive effects of dietary fatty acid and the susceptibility of rats to dietary cholesterol on the serum cholesterol concentration and hepatic mRNA abundance of the low-density lipoprotein (LDL) receptor, cholesterol 7alpha-hydroxylase (7alpha-hydroxylase) and 3-hydroxyl-3methylglutaryl (HMG) CoA reductase were examined. Both strains were fed on a diet supplemented with 10% each of olive, safflower or coconut oil with or without the addition of 1% cholesterol for one week. The ExHC rats fed on olive, safflower and coconut oil in combination with cholesterol respectively resulted in a 3.5-, 2.0- and 2.1-fold higher serum cholesterol concentration than that in the animals fed on the corresponding dietary fats without any supplementation of cholesterol (p < 0.01 by dietary cholesterol or type of fat). The dietary cholesterol dependent-elevation of serum cholesterol in the SD rats was less than 1.5-fold (p<0.01) and there was no dietary fat effect. The ExHC rats fed on the safflower oil-containing diet supplemented with cholesterol resulted in a higher mRNA abundance of the LDL receptor and 7alpha-hydroxylase than in the corresponding fat-fed rats without cholesterol (p<0.05). There was no dietary cholesterol-dependent change of mRNA abundance in either strain fed on olive or coconut oil, except for a decreased abundance of HMG CoA reductase mRNA in the olive oil-fed ExHC rats and coconut oil-fed Sprague-Dawley (SD) rats (p<0.05). These results indicate that the hepatic mRNA abundance of the LDL receptor and of 7alpha-hydroxylase depended on the dietary combination of cholesterol and a fatty acid and suggest that a linoleic acid-rich diet may alleviate exogenous hypercholesterolemia by activating the process involved in the hepatic uptake and biliary excretion of serum cholesterol.

Animals↗
PubMed1991

Effect of coconut oil & safflower oil on lipids in isoproterenol induced myocardial infarction in rats.

Effect of feeding safflower oil and coconut oil in experimental myocardial infarction induced by isoproterenol in rats was studied. Based on the survival rate and histopathological examination, safflower oil was found to offer better protection than coconut oil. Serum GOT levels also confirmed the protective activity of safflower oil. The concentrations of cholesterol and triglycerides in the heart and aorta were lower in the safflower oil fed group, while the level of phospholipids was higher.

Animals↗
PubMed1994

Dietary fish oil and olive oil improve the liver insulin receptor tyrosine kinase activity in high sucrose fed rats.

In order to shed light on the possible beneficial effect of dietary unsaturated fatty acids on insulin binding, the effect of fish oil and olive oil administration on insulin binding, autophosphorylation and tyrosine kinase activity of partially purified liver insulin receptors were investigated. These data were confronted with the parameters of sugar and lipid metabolism (blood glucose, insulin and triglycerides), with liver plasma membrane fluidity and fatty acid composition. High sucrose feeding resulted in the elevation of blood glucose and triglyceride level, while the supplementation of animals with fish oil reduced that of triglycerides and olive oil that of insulin. Any significant changes between experimental groups were not detected either in insulin binding to partially purified liver insulin receptor nor in receptor autophosphorylation. However, the insulin stimulated tyrosine kinase activity towards an exogenous substrate (poly(Glu,Tyr)) was decreased by about 50% in the receptors solubilized from liver membranes of sucrose fed rats. Increased dietary intake of fish oil or olive oil restored the activity of insulin tyrosine kinase towards control values, half maximal effect being obtained at similar insulin concentration in all groups. Such improvement might be due to the induced increase of membrane fluidity by unsaturated fatty acids, and/or to the decrease of insulinemia.

Animals↗
PubMed1997

[Changes in lipid profile of young persons after substitution of sunflower oil by olive oil in the diet].

BACKGROUND AND OBJECTIVES: There is controversy in determining the effects of olive oil in the lipidic metabolism. We studied the changes produced in the lipid profile after substituting sunflower dietetic oil with virgin olive oil. POPULATION AND METHODS: We studied 154 cadets of Academia General Militar de Zaragoza (AGEMZA), analyzing their smoking habits, anthropometric measures and dietetic intake. Hematologic, biochemical and lipidic parameters were determined in venous blood samples. All sunflower dietetic oil was substituted with olive oil, without making any other qualitative-quantitative variation in the diet 10 weeks after which the morphometric and analytical evaluation was repeated, comparing both measurements. RESULTS: 87% of cadets took part in the study. 34.3% of them were smokers. There were no significant anthropometric changes. After the interventional period, there was a decrease of 12.2% in total cholesterol (166.6 vs 146.2 mg/dl; p < 0.0001), 13.5% in LDL-cholesterol (99.7 vs 86.2 mg/dl; p < 0.0001), 12.2% in triglycerides (71.1 vs 62.4 mg/dl; p < 0.0001), 9.9% in HDL-cholesterol (52.6 vs 47.4 mg/dl; p < 0.001), despite which total-cholesterol/HDL-cholesterol ratio increased 3.1% (3.2 +/- 0.7 vs 3.1 +/- 0.7; p < 0.001). There were no changes in Lp(a) plasmatic concentrations or hematologic or biochemical parameters. CONCLUSION: The improvement of the lipidic parameters can only be explained by the use of olive oil in the diet of the AGEMZA cadets.

Adolescent↗
PubMed2002

Studies of synergism/antagonism for lowering dynamic interfacial tensions in surfactant/alkali/acidic oil systems. 1. Synergism/Antagonism in surfactant/model oil systems.

Experimental studies are conducted in order to elucidate the mechanisms responsible for synergism/antagonism for lowering dynamic interfacial tension in model oil/surfactant/brine systems. A well-defined model oil is selected for controlled design of experiments, thus enhancing verification of known and unknown mechanisms. The systems examined contain model oils and two petroleum sulfonate solutions. The influence of additives in oil phase, such as carboxylic acids with different chain length, n-octadecanol, and oil soluble surfactant SP-60, on the equivalent alkane carbon number (EACN) values has been examined. The interfacial tensions of different model oils with different EACN values against surfactant solutions with different n(min) values have also been obtained. We find that antagonism has been observed when EACN/n(min) value is far from unity by adding organic components, while synergism has been observed when EACN/n(min) value is close to unity. The results present here suggest that organic additives in oil phase controlled interfacial tension by changing the partition of surfactants in oil phase, aqueous phase, and interface.

Journal Article↗
PubMed1996

Effects of dietary triacylglycerol structure on triacylglycerols of resultant chylomicrons from fish oil- and seal oil-fed rats.

We investigated the influence of the intramolecular fatty acid distribution of dietary triacyl-sn-glycerols (TAG) rich in n-3 polyunsaturated fatty acids (PUFA) on the structure of chylomicron TAG. Fish oil and seal oil, comparable in fatty acid compositions but with different contents of major n-3 PUFA esterified at the sn-2 position (20:5n-3, 46.6%, and 5.3%; 22:6n-3, 75.5%, and 3.8%, respectively), were fed to rats. Mesenteric lymph was collected and the chylomicrons were isolated by ultracentrifugation. The fatty acid composition of chylomicrons largely reflected the fatty acid composition of the oils administered. The intramolecular fatty acid distributions of the TAG fed were reflected in the chylomicron TAG as the fraction of the total contents observed in the sn-2 position of 20:5n-3 were 23.6 and 13.3%, and of 22:6n-3 were 30.6 and 5.4% for resultant chylomicrons following fish oil and seal oil administration, respectively. Thus, after seal oil administration, significant higher load of n-3 PUFA was esterified in the sn-1,3 positions of chylomicron TAG compared with fish oil administration (P < 0.05).

Animals↗
PubMed1984

Study of long term effects of oil and oil-dispersant mixtures on freshwater microbial populations in man made ponds.

In this paper, the results of a 19 month investigation of microbial communities subjected to the effects of oil and oil plus dispersant additions in man made ponds are reported. Microbial biomass estimations by ATP (adenosine triphosphate) and microscopic procedures using epifluorescence indicated that oil and oil plus dispersants had little or no effect on these parameters, and any effect noted was stimulatory. However, detailed examination of specific populations indicated that oil and oil plus dispersant additions were stimulatory for short periods of time to the populations studied. Seven days after the oil and dispersant additions to the ponds, no mutagenic or toxic activities to bacteria were noted.

Adenosine Triphosphate↗
PubMed2004

Safety aspects regarding the consumption of high-dose dietary diacylglycerol oil in men and women in a double-blind controlled trial in comparison with consumption of a triacylglycerol control oil.

With the approval for use in foods in Japan and the United States, the use of diacylglycerol (DAG) oil in fat-based products may become extensive due to equivalent physicochemical properties to conventional triacylglycerol (TAG) oil. The objective of the present study was to compare the effects of high-dose consumption of DAG oil in humans with that of TAG oil. In a double-blind controlled parallel trial, moderately lean men (n=42) and women (n=39) consumed either DAG or TAG at a dose of approximately 0.5 g/kg body weight/day as part of their diet for 12 weeks. All subjects completing the study tolerated the test oils well and showed no overt effects. Total caloric and fat intake remained constant and showed no significant differences between the groups. There was no significant difference in the occurrence of clinical signs and physical complaints related to test oil consumption. Although some statistically significant effects were reported in hematological and serum chemistry parameters in both DAG and TAG groups, none of these reported changes were considered biologically significant. Overall, this 12-week clinical study revealed no significant or treatment-related adverse effects of DAG oil consumed at a dose of 0.5 g/kg of body weight/day as part of the diet.

Adult↗
PubMed2004

Garlic induced alteration in liver mineral concentrations in corn oil and olive oil fed rats.

This study was undertaken to compare the effects of 2% garlic (G) on liver mineral concentrations in rats fed with corn oil (C) or olive oil (O). Male Sprague-Dawley rats (n = 4 per group) were fed AIN76A semi-purified diets containing either 5% corn oil or 5% olive oil replacing corn oil with or without 2% garlic for 21 days. The analysis of minerals calcium (Ca), phosphorous (P), potassium (K), magnesium (Mg), manganese (Mn), sodium (Na), Sulfur (S), copper (Cu), iron (Fe) and zinc (Zn) of liver were conducted by inductively coupled plasma (ICP) spectroscopic method. In the C fed rats addition of 2% garlic produced significant increase in liver Ca, P, Mg, S, Mn, Cu, and Zn. There was no significant change in Fe, Na and K. In contrast, in olive oil fed rats, 2% garlic diets did not affect Ca, Mg, S, Mn, Na and K concentrations. However, there was significant decrease in liver Cu and Zn concentrations. Also, in O fed control rats liver, Ca, P, Mg, S, Fe, Mn, Cu, and Zn concentrations were significantly increased as compared to C fed control rats. In conclusion, this study describes the interactions between dietary oils and garlic on liver mineral concentrations in rats.

Journal Article↗
PubMed1996

Effects of fish oil and safflower oil emulsions on diet-induced hepatic steatosis in rats receiving total parenteral nutrition.

This study was conducted to investigate the effects of fish oil and safflower oil emulsions in total parenteral nutrition (TPN) solutions on diet-induced hepatic steatosis. Rats were divided into a control group (C, n = 6) and four experimental groups (A, B, S, F, n = 11 approximately 14). The control group was fed a chow diet whereas the experimental groups received a high fat (15%, w/w) diet containing 0.1% (w/w) cholesterol. Group A received the high fat diet for 4 weeks, and was killed at the end of the fourth week to ensure that hepatic steatosis had occurred. Groups S and group F received TPN with safflower oil or fish oil emulsions, respectively, for 1 week following experimental diet feeding for 4 weeks. Group B was fed a limited amount of the high fat diet, without cholesterol, for 1 week following 4 weeks of experimental diet in order to maintain the same body weight and cholesterol intake as the TPN groups. Diet-induced hepatic steatosis was observed in the experimental groups. Fat deposition was reversed when the total caloric and cholesterol intake was reduced. Fish oil infusion ameliorated the severity of hepatic steatosis, whereas safflower oil had no effect on liver fat deposition. These results suggest that TPN with fish oil emulsions may be beneficial to patients with diet-induced hepatic steatosis.

Journal Article↗
PubMed2005

Effects of type and physical properties of oil phase on oil-in-water emulsion droplet formation in straight-through microchannel emulsification, experimental and CFD studies.

Straight-through microchannel (MC) emulsification is a novel technique for formulating monodisperse emulsions using an array of micrometer-sized channels vertical to the surface of a silicon plate (a straight-through MC). We studied the effects of the type and physical properties of the dispersed oil phase and of the surfactant concentration on droplet formation from a straight-through MC by experiments and computational fluid dynamics (CFD) simulations. Monodisperse oil-in-water emulsions with coefficients of variation below 4% were formulated from an oblong straight-through MC using silicone oils, tetradecane, medium-chain triglyceride, soybean oil, and liquid paraffin as the oil phase. At oil viscosities (eta(d)) lower than a threshold value of 100 mPa s, the values of the resultant droplet diameter (d(ex)) gradually decreased with increasing eta(d), whereas they were not affected by the surfactant concentration. Conversely, at eta(d) higher than the threshold value, the d(ex) values significantly increased with increasing eta(d), and they were affected by the surfactant concentration. An analysis on the basis of droplet formation time and interfacial tension clarified that the trends in d(ex) at eta(d) above the threshold value would be caused by the significant decrease in the dynamic interfacial tension during droplet formation. We thus discovered that the dynamic interfacial tension is also a parameter affecting the d(ex) along with eta(d) in straight-through MC emulsification. CFD simulations using a three-dimensional (3D) model including a straight-through MC confirmed successful formation of micrometer-sized droplets for the above-mentioned oils. The experimental and CFD results for the resultant droplet size were compared using the dimensionless droplet diameter (d, droplet diameter/channel equivalent diameter). The d(CFD) values agreed well with the d(ex) values at eta(d) below the threshold value of 100 mPa s for all the experiment systems and at eta(d) above the threshold value for the experiment systems that did not contain a surfactant.

Journal Article↗
PubMed1998

Strategies to improve the nutritive value of rice bran in poultry diets. II. Changes in oil digestibility, metabolisable energy and attempts to increase the digestibility of the oil fraction in the diets of chickens and ducklings.

1. In experiment 1, the effects of age on oil digestibility and apparent metabolisable energy (AME) were measured in chickens and ducklings between 3 and 28 d of age on a diet with 400 g rice bran/kg. In experiment 2, a biosurfactant and a food lipase were added to diets of chickens containing 200 and 400 g rice bran/kg. In experiment 3, chicken diets containing 0 or 400 g rice bran/kg were supplemented with a food lipase (2 concentrations) or a food enzyme or their combination. 2. In experiment 1, oil metabolisability and AME increased substantially as chickens aged. Oil metabolisability was much higher in ducklings, when comparisons were made with chickens of similar age. 3. In experiment 2, lipase or biosurfactant gave no improvement in bird performance. Growth rate and food conversion ratio were, respectively, 23% and 10% better on diets with 200 compared to 400 g rice bran/kg. 4. In experiment 3, there was a significant growth response to lipase plus the enzyme mixture on the diet with 200 g rice bran/kg. On the diet with 400 g rice bran/kg, growth improvement was seen with the enzyme mixture only. 5. In experiment 3, enzyme addition did not increase oil metabolisability or AME. At 4 to 8 d of age AME was higher on the diet without rice bran but oil metabolisability was the same as on the diet with rice bran. At 19 to 23 d of age AME was similar but oil metabolisability was higher on the diet with rice bran than without. Droppings' dry matter was higher on diets without than with rice bran (32.4 vs 27.1%). 6. The response to lipase and the combination of this and a food enzyme suggest that there may be benefit in examining this interaction further although they had no effect on oil metabolisability or on AME. It is concluded that a stable AME for rice bran cannot be provided for chickens until at least 21 d of age.

Aging↗
PubMed2006

Deep desulfurization of diesel oil and crude oils by a newly isolated Rhodococcus erythropolis strain.

The soil-isolated strain XP was identified as Rhodococcus erythropolis. R. erythropolis XP could efficiently desulfurize benzonaphthothiophene, a complicated model sulfur compound that exists in crude oil. The desulfurization product of benzonaphthothiophene was identified as alpha-hydroxy-beta-phenyl-naphthalene. Resting cells could desulfurize diesel oil (total organic sulfur, 259 ppm) after hydrodesulfurization. The sulfur content of diesel oil was reduced by 94.5% by using the resting cell biocatalyst for 24 h at 30 degrees C. Biodesulfurization of crude oils was also investigated. After 72 h of treatment at 30 degrees C, 62.3% of the total sulfur content in Fushun crude oil (initial total sulfur content, 3,210 ppm) and 47.2% of that in Sudanese crude oil (initial total sulfur, 1,237 ppm) were removed. Gas chromatography with pulsed-flame photometric detector analysis was used to evaluate the effect of R. erythropolis XP treatment on the sulfur content in Fushun crude oil, and it was shown that most organic sulfur compounds were eliminated after biodesulfurization.

Gasoline↗
PubMed2003

[Two phases bioremediation of oil contaminated soil from Liaohe oil field].

A treatment engineering of prepared bed was set up for the bioremediation of oil contaminated soil with oil in this study, soils contaminated with different type of oils were treated using composting process in the prepared bed and the treatment period was divided into 2 phases with total time of 210 days. When the concentration of total petroleum hydrocarbons (TPH), which consist of thin oil, high condensation oil, special viscous oil, and viscous oil, were in the range of 25.8-77.2 g.kg-1 dry soil, petroleum removal rates can reach 38.37%-56.74% by 53 days operation. In the second phase, total petroleum removal rates reached 66.59%-80.96% by the 156 days operation in the next year. The results showed that most hydrocarbon pollutants that are easier to be degraded were removed in the first phase, the remedying efficiency obviously dropped in the second phase.

Bacteria↗
PubMed1981

Changes in composition and enzyme activities of mitochondrial and post-mitochondrial fractions of tissues of rats given mustard oil diet with carnitine and/or fish oil.

The effects of short-term feeding of a 20% mustard oil (containing 47% erucic acid) diet with 0.1% carnitine and/or fish oil on the activity of enzymes of lipid metabolism in mitochondrial and post-mitochondrial fractions of heart, liver, and skeletal muscles of rats were determined to study the reversal of erucic acid-induced lipidosis. Histopathological changes were also studied. The inclusion of fish oil or fish oil plus carnitine in a mustard oil diet, especially the latter, eliminated the histopathologically detectable lipidosis in heart and skeletal muscles. The reason for this appears to be the increased activity of lipase and phospholipase in tissue homogenates and of cholesterol ester hydrolase in the post-mitochondrial fraction; and also an increase in mitochondrial succinate dehydrogenase which may increase the utilization of the liberated fatty acids. The results suggest that the erucic acid-induced lipidosis is prevented or eliminated by increased lipolysis and oxidation of fatty acids when such a diet is supplemented with carnitine and/or fish oil.

Animals↗
PubMed1986

The effect of feeding fish oils, vegetable oils and clofibrate on the ketogenesis from long chain fatty acids in hepatocytes.

Groups of rats were fed diets containing 25% fish oil (FO), 25% soybean oil, 25% partially hydrogenated fish oil (PHFO), 25% partially hydrogenated soybean oil (PHSO), 25% partially hydrogenated coconut oil or 0.3% clofibrate for 3 wk. After the animals were fasted for 24 hr, hepatocytes were isolated and ketogenesis from added palmitate, linoleate cis and trans, arachidonate and docosahexaenoate was measured. Ketogenesis after oil feeding was significantly stimulated (two- to threefold) only in cells from the PHFO- and PHSO-fed rats. The stimulation was most apparent with the long chain unsaturated fatty acids as substrates. These fatty acids were relatively poor ketone body precursors in control hepatocytes. Essential fatty acid deficiency did not seem to be the reason for this stimulation. Clofibrate also stimulated ketogenesis significantly (1.5- to 3-fold). The degree of stimulation increased with chain length and degree of unsaturation of the substrate. The activity of the enzyme 2,4-dienoyl-CoA reductase was also studied in the same groups. Its activity was stimulated about fourfold in the clofibrate-treated rats and to a lesser extent by the PHFO, PHSO and FO diets. The activity showed no correlation with the content of unsaturated fatty acids in the diet or their oxidation in isolated hepatocytes. The 2,4-dienoyl-CoA reductase, therefore, does not seem to be a regulatory enzyme in the metabolism of dietary polyunsaturated fatty acids. It is concluded that an induction of the peroxisomal beta-oxidation system most likely is involved in the reported increases in ketogenesis from very long chain polyunsaturated fatty acids.

Animals↗