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1.
Representative cottonseed salad oils, corn oils, lards and hydrogenated vegetable shortenings, and portions of the same fats
heated at 182 C for 120 hr were fed as 20% of nutritionally adequate diets to weanling albino rats in longevity studies. Differences
in the responses of rats fed diets containing the unheated and heated fats were generally small with respect to rates of gain,
12 th week and adult weights, efficiencies of utilization of absorbed energy, incidences of grossly detectable diseases and
longevities. There were no indications that the feeding of the heated fats had shortened survival times in comparison with
the comparable unheated fat. Animals fed hydrogenated vegetable shortening, heated or unheated, survived the longest. However,
gains were slightly slower with the heated cotton-seed oil diets, and food efficiencies were slightly lower with the heated
cottonseed oil and heated lard diets because of decreased digestibilities of these fats. The usual disabilities of old age
such as nephritis, respiratory disease and periarteritis were present in all groups. The incidence of mammary tumors was high
but did not differ significantly with the kind of fat, heaated or unheated. Tumor incidence other than mammary was similar
in both sexes and there was no significant difference between fresh and heated fats. Absence of adverse effects attributable
to the heated fats during the life span of the rats in further evidence of the safety of these fats of the quality customarily
consumed by the human population. 相似文献
2.
In an effort to reduce the deleterious nutritional effects of oxidation products generated in heated fats, a partially hydrogenated
soybean oil (PHSBO) used 7 d (7-DH) for frying foodstuffs was obtained from a commercial deep-fat frying operation. The used
fat was treated with magnesium silicate (T-7DH). Isocaloric diets containing 15% of either 7-DH or T-7-DH fats were prepared
and fed to male weanling rats for 10 wk in a pair-feeding experiment and compared to control rats fed nonheated PHSBO (NH).
Animals fed the 7-DH diet showed higher liver enzyme cytochrome b5 and P450 activity than the T-7DH diet compared to the NH group, suggesting a positive effect of the treatment. These results suggested
the presence of lower amounts of harmful compounds in the diet containing the heated used oil which had been treated with
the active adsorbent. 相似文献
3.
A semisynthetic diet containing 15% by weight of dietary fat was fed to six groups of male Wistar rats for 28 days. Two groups
received the distilable fraction of fresh corn oil (DCO) or fresh olive oil (DOO), two groups the distillable fraction of
the thermally oxidized fats (OCO,OOO), and two groups received the respective fresh fats as controls (FCO, FOO). Substantial
changes in the fatty acid composition occurred in the fats upon thermal oxidation. Only the rats that received OOO showed
overt symptoms of heated fat toxicity. This was reflected in the histological scores of these animals, with the liver sustaining
the most numerous and severe lesions. Tissue fatty acid changes of any significance were confined largely to the polar liver
lipids of the rats that were fed OCO or OOO. The results of this study would suggest that the relatively greater toxicity
of OOO, compared to OCO, may in part be due to the high oleic:linoleic acid ratio of the fresh olive oil and in part to a
higher tocopherol content of the corn oil. 相似文献
4.
Fresh and oxidized cotton seed oil (CO) olive oil (OO), chicken fat (CF) and beef fat (BF) were fed to male weanling rats
for 33 to 108 weeks. Groups fed oxidized fats except OO showed a higher death rate than those fed the corresponding fresh
fats. Groups fed oxidized CO and BF had the highest death rate. Histological studies of animals dying from natural causes
showed more pronounced cardiac lesions in the animals fed oxidized CO. Serum, liver and brain cholesterol levels were not
influenced by oxidized fats. Fatty acid composition of depot fats and of heart and liver lipids did not show significant differences
between groups fed fresh and the corresponding oxidized fats.
Presented at the Spring Meeting of the AOCS 1964. 相似文献
5.
G. A. Nolew 《Journal of the American Oil Chemists' Society》1981,58(1):31-37
A 91-day feeding study evaluated soybean oil, rapeseed oil, fully hydrogenated soybean oil, fully hydrogenated rapeseed oil,
fully hydrogenated superglycerinated soybean oil and fully hydrogenated superglycerinated rapeseed oil at 7.5% of the diet
in rats; a 16-wk feeding study evaluated soybean oil and the three rapeseed oils or fats at 15% of the diet. Each fat was
fed to 40 rats as a mixture with soybean oil making up 20% of a semi-synthetic diet. No significant differences in body weight
gains or diet-related pathology were seen in the 91-day study although the rats fed liquid rapeseed oil had slightly heavier
hearts, kidneys and testes than the others. The rats fed the four fully hydrogenated fats ate more feed and had lower feed
efficiencies than those fed oils but no differences were seen among the four hydrogenated fats. In the 16-wk feeding study,
no pronounced pathology related to the diet was seen although the rats fed liquid rapeseed oil had a slightly higher incidence
of histiocytic infiltration of cardiac muscle than the rats in the other groups. The female rats fed the three rapeseed oil
fats gained significantly less weight and the females fed liquid rapeseed oil had enlarged hearts compared to the other groups.
The absorbabilities of the six fats were measured in the 91-day study when fed as a mixture with soybean oil and as the sole
source of dietary fat in a separate 15-day balance study. The four fully hydrogenated fats were poorly absorbed and the absorption
of behenic acid from the two hydrogenated rapeseed oils was found to be 12% and 17% in the balance study and 8-40% in the
feeding study. The adverse biological effects of unhydrogenated rapeseed oil containing erucic acid as reported in the literature
do not occur with fully hydrogenated rapeseed oil. In addition, the low absorbability of the fully hydrogenated rapeseed oil
is an added factor in its biological inertness. 相似文献
6.
The objective of this study was to evaluate the effects of dietary heated fats from a commercial deep-fat frying operation
on rat liver enzyme activity. The fats, partially hydrogenated soybean oil (PHSBO) used for four days and for 7 days (7-DH)
for frying foodstuffs in a commercial restaurant, were fed to rats in either free access to food or by pair-feeding graded
doses. All diets were isocaloric and contained 15 g/100 g of diet. Experiments were conducted with control rats fed nonheated
(NH) PHSBO diet. Animals fed 7-DH diet in each set of experiments had larger amounts of cytochromes P450 and b5 and greater activity of NADPH-cytochrome P450 reductase when compared to controls. The activities of carnitine palmitoyltransferase-I and isocitrate dehydrogenase were
significantly lower in rats fed test diets in comparison to controls. A significantly depressed activity of glucose 6-phosphate
dehydrogenase was also noticed for these animals when compared to those fed NH. In addition, liver and microsomal protein
concentrations were significantly greater in rats fed the used oils in comparison to controls, and liver glycogen was significantly
lower. 相似文献
7.
Nutritional evaluation of a medium-chain triglyceride (MCT) preparation, containing about 75% octanoic acid and 25% decanoic
acid, was carried out in short- and long-term experiments in rats. A casein diet containing 19.6% MCT and 2.5% safflower oil,
the latter to supply essential fatty acids, was compared with similar diets containing conventional dietary fats. Data obtained
in a 47-week study showed that the MCT diet supported normal growth and development. At autopsy, carcass protein and ash levels,
vital organ weights and composition were similar to those in rats fed conventional fats. Histological study showed that intestinal
and liver sections were normal after 47 weeks on the MCT-containing diet. In general, rats fed MCT had slightly lower growth
rates and caloric efficiency values, less carcass fat and smaller epididymal fat pads than animals fed conventional dietary
fats. Little C8 and C10 were found in depot fat. The MCT diet also supported normal reproducton, as indicated by litter size and number. During lactation
the volume of milk secreted by the rats receiving the MCT diet was smaller and contained a lower level of fat than that secreted
by the rats receiving an oleo oil diet, resulting in slower gains in weight in the MCT group. After weaning, growth of the
rats fed MCT compared favorably with that attained by the animals on the diet containing oleo oil. 相似文献
8.
Groups of 40 male Charles River rats were fed diets containing cottonseed oil, olive oil, corn oil, soybean oil, coconut oil,
chicken fat, beef fat, butter oil, lard and saturated medium chain triglycerides. The fats were fed fresh and after 40 hr
aeration at 60 C, which hardly changed peroxide values. In addition, fresh and aerated soybean oil and lard were fed to W/Fu
rats. Body weights and life span were significantly influenced by the kind of fat fed, but not by aeration. Many hearts exhibited
unspecific focal myocarditis and focal fibrosis. The latter was graded in a blind test, which revealed highly significant
differences in the incidence of severe lesions; those fed corn oil had the most, followed by cottonseed oil, soybean oil,
olive oil, beef fat, saturated medium chain triglycerides, butter, chicken fat and lard, in that order. Feeding of aerated
fat resulted in an increased incidence with six of the eight fats. The W/Fu rats had lower incidences, but those fed soybean
oil had more than those fed lard, and aeration led to a higher incidence. Some heart sections stained with Light Green SF
Yellowish revealed areas of muscle fibrils that did not accept the stain, probably as a consequence of cellular damage. Higher
incidences of this lesion were associated with the same fats as was severe fibrosis, and feeding of aerated fats led to higher
incidences. Many livers revealed marked proliferation of bile ducts. The groups fed cottonseed, soybean, olive and corn oils
had higher incidences of severe lesions, and feeding of the oxidized oils led to still higher incidences. None of the results
appeared to be associated with the fatty acid composition of the fats, which suggested that these long term effects may have
been due to minor constituents in the individual fats.
One of seven papers presented in the symposium “Biological Significance of Autoxidized and Polymerized Oils,” JOCS-AOCS Joint
Meeting, Los Angeles, April 1972. 相似文献
9.
We have previously proposed that thermally processed oil holds promise as a dietary supplement intended for weight loss. We employed a thermal process whereby oil was heated to 180 degrees C for 10 h in the absence and presence of gluten. We compared the effects of three diets, untreated oil, heated oil, heated oil and gluten on body weight, retroperitoneal weight and lipid composition and fecal lipid contents. Ten week-old male Wistar rats were fed ad libitum a diet containing 7 wt% of the oil for 12 weeks. The oil heated with gluten showed low levels of food efficiency and oil absorption ratios, and high levels of fecal oil excretion, oil content and bile acid content. Diets containing thermally treated oils resulted in significantly lower retroperitoneal tissue weights and lipid contents as compared to the control group; the groups fed the heated oil and gluten diets showed a general decrease in the fatty acid (especially linoleic acid) amount. In conclusion, oil heated with gluten was not fully digested and thus excreted without showing any detrimental effects on either the organs or feces. This resulted in safe and effective weight loss in growing adult rats. 相似文献
10.
Groups of rats were prefed for 18 weeks with fresh or heated corn oil (≈5% nonurea adduct) at 10, 20 and 30% protein levels
and at 10% protein+2% cellulose; 1-14C-sodium acetate was injected intraperitonially into each animal and the radioactivity was measured in expelled CO2 and also in the lipid fractions of liver. In the groups of rats fed 10% protein, one-half of the administered radioactivity
was found 50 min after acetate injection into rats fed fresh oil, whereas 90 min were required to reach the same level in
rats fed heated oil. The same trend was found in all the groups of rats receiving different protein levels. The conversion
of acetate to CO2 was significantly higher at a 10% dietary protein level than at the 20 or 30%, but there appeared to be no significant difference
in the conversions at the 20 and 30% protein levels. However addition of 2% cellulose to the 10% dietary protein level significantly
increased the conversion of the acetate to CO2 in rats fed heated oil. The livers of animals receiving heated fat diets had a higher lipid content, mainly triglyceride.
When the liver lipids from rats fed fresh corn oil were separated by argentation thin layer chromatography, the bulk of the
radioactivity was found in the saturated fractions. Monoene, diene and triene fractions from the liver lipid of rats fed heated
oil had almost twice the radioactivity of those from fresh oil, suggesting the preferential utilization of acetate in the
synthesis of these unsaturated fatty acids.
One of seven papers presented in the symposium “Biological Significance of Autoxidized and Polymerized Oils”, JOCS-AOCS Joint
Meeting, Los Angeles, April 1972. 相似文献
11.
Roslyn B. Alfin-Slater Sheila Auerbach Lilla Aftergood 《Journal of the American Oil Chemists' Society》1959,36(12):638-641
Summary Soybean oil, cottonseed oil, and lard were heatedin vacuo for either 70 and/or 100 min. at 610°F. and were fed to male and female rats at a level of 15% in the diet over a complete
life span. Nutritional indices such as growth, including food efficiency and digestibility of the fats, reproduction and lactation,
longevity, and tissue cholesterol and total lipid were measured. No evidence of impaired nutrition or harmfulness was observed
in any group except in those fed the more highly polymerized soybean oil, where a decrease in iodine value of 10% and a 100%
increase in viscosity was associated with a slight depression in growth and an interference with reproductive performance
in the female animal. This interference with the reproductive process was alleviated by supplementation with α-tocopherol.
There was no evidence of increased tumor incidence in the groups ingesting the heated oils. Digestibility of the heated soybean
and cottonseed oils was only slightly reduced.
Presented at the fall meeting, American Oil Chemists' Society, Chicago, Ill., October 21, 1958.
Contribution No. 467. 相似文献
12.
We previously proposed that oil heated with gluten was suitable for use as a safe oil for weight-loss dieting. In the present paper, the properties of the oil were improved, and the weight-loss effect was compared with that of heated oil. Fresh oil was heated for 10 h at 180 degrees C with or without gluten and filtered using filter paper. A powdered diet (AIN93G; no fat) was mixed with 7 wt% of fresh oil (control) or filtrates of the heated oils described above, and the mixture was fed to male Wistar rats for 12 weeks. The gluten and heated oil groups showed no gross symptoms attributable to the experimental oils but had a slowed body weight increase; a significant difference was found in weight on and after 21 weeks of age as compared to rats consuming the control diet, and fecal excretion was increased as compared to the control group. Serum levels of triacylglycerol, phospholipids, cholesterol, and glucose of the gluten and heated oil groups were significantly lower than those of the control group. High aspartate aminotransferase (AST) levels occurred more frequently in the heated oil group than the gluten group. The number of rats with dark red patches on the surface of the liver, which are indicative of liver damage, was higher in the heated oil group. In conclusion, the weight-reducing effect of the oil heated with gluten was confirmed and improved by removing traces of heated gluten from the oil. 相似文献
13.
This study was conducted to investigate the effects of dietary cyclic fatty acid monomers (CFAM), contained in heated fat
from a commercial deep-fat frying operation, on rat liver enzyme activity. A partially hydrogenated soybean oil (PHSBO) used
7 d (7-DH) for frying foodstuffs, or 0.15% methylated CFAM diets was fed to male weanling rats in comparison to a control
group fed a nonheated PHSBO (NH) diet in a 10-wk experiment. All diets were isocaloric with 15% fat. Animals fed either CFAM
or 7-DH diets showed increased hepatic content of cytochrome (cyt.) b5 and P450 and increased activity of (E.C. 1.6.2.4) NADPH-cyt. P450 reductase in comparison to the control rats. In addition, the activities of (E.C. 2.3.1.21) carnitine palmitoyltransferase-l
and (E.C. 1.1.1.42) isocitrate dehydrogenase were significantly decreased when compared to that of rats fed the NH diet. A
significantly depressed activity of (E.C. 1.1.1.49) glucose 6-phosphate dehydrogenase was also observed for these animals
compared to the control rats fed NH diet. Moreover, liver and microsomal proteins were significantly increased when CFAM or
7-DH diets were fed to animals in comparison to controls while liver glycogen was decreased significantly in experimental
groups of rats. The results obtained in this study indicate that the CFAM in the diet from either synthetic sources or used
fats increase the activity of liver enzyme systems that detoxify them. 相似文献
14.
Male Wistar rats were fed ad libitum for 12 weeks a powdered diet (AIN93G; no fat) containing 7 wt% of fresh oil (control), and frying oils heated for 20 h at 180 degrees C with amino acids, gluten, sugar, and wheat starch, respectively. The rats were subjected to anthropometric measurements, hematological analyses, and observations of the liver and kidneys. All of the rats grew well, and no gross symptoms attributable to the experimental oils were observed. The serum of all the experimental groups showed a tendency toward lower levels of triacylglycerol and free fatty acids and higher levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) than that of the control group. Among experimental groups, the rats fed a diet containing oil heated with gluten were least influenced by thermally deteriorated oil in terms of serum levels of glucose, triacylglycerol, phospholipids, cholesterol, and insulin; histological evaluations; and number of dark-red patches found on the surface of the liver. 相似文献
15.
This study was undertaken to investigate the effect of dietary oxidized fats on the relative mRNA concentrations and the activities
of fatty acid synthase (FAS) and glucose-6-phosphate dehydrogenase (G6PDH) in the liver of rats treated with vitamin E or
selenium. Two experiments with male Sprague-Dawley rats were carried out. The first experiment included eight groups of rats
fed diets with either fresh fat or three different types of oxidized fat, preparated by heating at temperatures of 50, 105,
or 190°C, over a period of 6 wk. The diets contained either 25 or 250 mg α-tocopherol equivalents per kg. The second experiment
included four groups of rats fed diets with fresh fat or oxidized fat, heated at a temperature of 55°C, containing either
70 or 570 μg selenium per kg, over a period of 8 wk. Feeding the diets with oxidized fats led to a significant overall reduction
of the relative mRNA concentrations and the activities of FAS and G6PDH in both experiments. The effects of the oxidized fats
on mRNA concentrations and activities of these enzymes were independent of the dietary concentrations of vitamin E or selenium.
Moreover, in both experiments the rats whose diet contained the oxidized fats had significantly lower concentrations of TG
in liver, plasma, and VLDL than the rats whose diet contained fresh fat. The study suggests that oxidized fats contain substances
that suppress gene expression of lipogenic enzymes in the liver. 相似文献
16.
Male Sprague Dawley rats were fed semipurified diets containing 20% fat for 15 weeks. The dietary fats were corn oil, soybean
oil, palm oil, palm olein and palm stearin. No differences in the body and organ weights of rats fed the various diets were
evident. Plasma cholesterol levels of rats fed soybean oil were significantly lower than those of rats fed corn oil, palm
oil, palm olein or palm stearin. Significant differences between the plasma cholesterol content of rats fed corn oil and rats
fed the three palm oils were not evident. HDL cholesterol was raised in rats fed the three palm oil diets compared to the
rats fed either corn oil or soybean oil. The cholesterol-phospholipid molar ratio of rat platelets was not influenced by the
dietary fat type. The formation of 6-keto-PGF1α was significantly enhanced in palm oil-fed rats compared to all other dietary treatments. Fatty acid compositional changes
in the plasma cholesterol esters and plasma triglycerides were diet regulated with significant differences between rats fed
the polyunsaturated corn and soybean oil compared to the three palm oils. 相似文献
17.
Fresh oil was heated for 20 h at 180 degrees C with amino acids or gluten. A powdered diet (AIN93G; no fat) was mixed with 7 wt% of fresh oil (control), or supernatants of the heated oils described above, and fed to male Wistar rats for 12 weeks. No gross symptoms attributable to the heated oils were observed, but the gluten group showed a slow body weight increase; a significant difference was found in the weight after age 21 weeks in spite of diet consumption comparable to that of the control group. The serum of the heated oil groups showed a tendency toward lower values on various hematological measures, especially triacylglycerol and free fatty acid and toward higher values on aspartate aminotransferase (AST) and alanine aminotransferese (ALT), than those of the control group. All the rats except one in the gluten group had the same level of AST as those of the control rats, while the amino acid group included four rats with AST over 100 IU/L, the highest value in the control group. The number of dark red patches found on the surface of the liver and histological evaluation also showed frequent damage to the livers of the amino acid group. The difference in toxicity between the two heated oils seems to be related to the molecular sizes of amino acids and gluten. Gluten or melanoidin produced during heating probably decreased or counteracted the cytotoxicity of thermally oxidized oil. It is expected that oil heated with gluten can be used as a safe and effective oil for humans on weight-reduction diets. 相似文献
18.
Dietary polyunsaturated fat versus saturated fat in relation to mammary carcinogenesis 总被引:3,自引:0,他引:3
High levels of dietary fat have been shown to promote the development of mammary tumors induced in rats by 7,12-dimethylbenz(α)anthracene,
and polyunsaturated fats were found to be more effective than saturated fats. In further studies it was found that diets containing
3% sunflowerseed oil (polyunsaturated fat) and 17% beef tallow or coconut oil (saturated fats) enhance tumorigenesis as much
as a diet containing 20% sunflowerseed oil. Rats on these diets developed at least twice as many tumors as those fed diets
containing either 3% sunflowerseed oil or 20% of the saturated fats alone. These results are in accord with human epidemiological
data which show that breast cancer mortality in different countries is positively correlated with total fat intake but not
with intake of polyunsaturated fat. Total fat intake varies greatly in different countries, but most human diets probably
contain levels of polyunsaturated fat at least equivalent to 3% sunflowerseed oil. 相似文献
19.
Rats were fed cholesterol, cacao butter, or olive oil diets to determine the effect of dietary lipids on the rate of drug
biotransformation in the liver and duodenum. The cholesterol rich diet maintained the hepatic aryl hydrocarbon hydroxylase
activity at the same level as did the standard diet. Rats fed olive oil and cacao butter diets showed lower hepatic aryl hydrocarbon
hydrorylase activity. The p-nitroanisole 0-demethylase activity was doubled in hepatic microsomes of rats fed the high cholesterol
diet when compared to rats fed the standard diet. The hepatic uridine diphosphate glucoronosyltransferase activity showed
different patterns depending on the in vitro treatment of the microsomal membranes. If the enzyme activity was assayed from
the native, untreated microsomes, an increase in the measurable uridine diphosphate glucuronosyl transferase activity was
found in rats having cholesterol rich diet. After the in vitro activation of membrane-bound uridine diphosphate glucuronosyltransferase
by trypsin, the increase in measurable activity was 10 fold in the group fed the standard diet, 6 fold in group fed cholesterol,
4 fold in group fed cacao butter, and 3 fold in group fed olive oil. Trypsin digestion of microsomes increased the measurable
uridine diphosphate glucuronosyltransferase activity less in rats fed diets rich in neutral fats than those fed the standard
diet. In the duodenal mucosa, lipid diets decreased the activities of drug hydroxylation and glucuronidation. 相似文献
20.
Female Sprague-Dawley rats on semisynthetic diets containing 10% and 20% by weight of corn oil developed more mammary adenocarcinomas
after treatment with a single oral dose of 7,12-dimethylbenz(α)anthracene than similar rats on diets containing only 0.5%
or 5% corn oil. Experiments with 10 different fats and oils fed at the 20% level indicated that unsaturated fats enhance the
yield of adenocarcinomas more than saturated fats. Fibroadenomas and adenomas were also found in small numbers in all dietary
groups but the yield did not seem to be influenced by level or type of dietary fat. The possible relevance of these findings
to the incidence of breast cancer in humans is discussed.
Presented at the ISF-AOCS World Congress, Chicago, September 1970. 相似文献