EFFECTS OF HYPOGLYCIN A ON THE METABOLISM OF AMINO ACIDS BY LIVER SLICES

1964 ◽  
Vol 42 (1) ◽  
pp. 139-142 ◽  
Author(s):  
S. J. Patrick ◽  
L. C. Stewart
Keyword(s):  
Amino Acids ◽  
Fatty Acids ◽  
Fatty Acid ◽  
Glutamic Acid ◽  
Rat Liver ◽  
Inhibitory Effects ◽  
Liver Slices

The effects of hypoglycin A on the metabolism of L-leucine-C14, L-alanine-C14, and L-glutamic-acid-C14 by rat liver slices have been investigated. Hypoglycin exerted markedly inhibitory effects on the conversion of leucine-C14 to fatty acid, cholesterol, and CO2. Conversion of alanine-C14 and glutamic acid-C14 to fatty acids was also inhibited by hypoglycin. No effects of hypoglycin on the conversion of C14-amino acids into protein or glycogen were demonstrated.

Effect of Adrenalectomy on the Incorporation of Acetate Into Fatty Acids, Cholesterol and Acetoacetic Acid by Rat Liver Slices

1955 ◽  
Vol 184 (1) ◽  
pp. 59-62 ◽  
Author(s):  
W. F. Perry ◽  
Helen F. Bowen
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Rat Liver ◽  
Acid Formation ◽  
Acetoacetic Acid ◽  
Adrenalectomized Animal ◽  
Liver Slices ◽  
Adrenalectomized Rats

The incorporation of C14 acetate into fatty acids, cholesterol, acetoacetic acid and CO2 by liver slices of intact and adrenalectomized rats was studied, the slices being incubated in bicarbonate and phosphate buffers. It was found that in both buffer systems incorporation into fatty acids and cholesterol was depressed while incorporation into acetoacetic acid was unaffected by adrenalectomy. However, total acetoacetic acid formation by the slices tended to be higher in preparations from adrenalectomized animals. The amount of acetate carbon appearing as CO2 was similar with slices from both types of animals. Bicarbonate was found to be a more favorable medium than PO4 for fatty acid formation, while PO4 was the more favorable medium for cholesterogenesis, though the differences between adrenalectomized and intact animals persisted in either buffer. Forced feeding with glucose increased the incorporation of acetate into fat and cholesterol in both buffer systems in adrenalectomized as well as in intact animals. However, the adrenalectomized preparation still incorporated acetate to a lesser extent than the controls. It was concluded that while the depressed incorporation of acetate into fatty acid and cholesterol by adrenalectomized liver slices was consistent with a depressed synthesis of these lipids, there was also the possibility that it reflected an increased turnover of lipids in the liver of the adrenalectomized animal.

Utilization of fatty acids by rat liver slices as a function of medium concentration

1964 ◽  
Vol 206 (2) ◽  
pp. 345-350 ◽  
Author(s):  
Herbert Rose ◽  
Martha Vaughan ◽  
Daniel Steinberg
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Rat Liver ◽  
Neutral Lipids ◽  
Specific Radioactivity ◽  
Lipid Synthesis ◽  
Normal Liver ◽  
Precursor Pool ◽  
Liver Slices

The rate of incorporation of palmitate-1-C14 into neutral lipids and phospholipids of rat liver slices in vitro and its conversion to C14O2 were shown to increase markedly as the free fatty acid (FFA) concentration of the medium was increased. Incorporation into lipids and conversion to C14O2 proceeded linearly with time over 60 min. The incorporation of glycerol-1,3-C14 into neutral lipids also increased as the FFA concentration of the medium was increased but incorporation into phospholipids was unchanged. It is concluded that high FFA concentrations cause a true increase in rate of neutral lipid synthesis by liver slices. The associated increase in incorporation of labeled palmitate into phospholipids most likely reflects the higher specific radioactivity of the precursor pool of FFA and/or an exchange reaction rather than a true increase in net synthesis. A method for recovering tissue FFA quantitatively is described. Normal liver was found to contain 0.40–0.87 µEq FFA/g wet wt. The composition of this tissue FFA fraction is presented.

scholarly journals The chemical composition of oyster nut (Telfairia pedata) seeds and oil

OCL ◽  
2021 ◽  
Vol 28 ◽  
pp. 1
Author(s):  
Paolo Bondioli ◽  
Liliana Folegatti ◽  
Gabriella Morini
Keyword(s):  
Amino Acids ◽  
Fatty Acids ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Chemical Composition ◽  
Glutamic Acid ◽  
Acid Composition ◽  
Protein Fraction ◽  
The Family ◽  
Mineral Constituents

In this paper, the chemical composition of Telfairia pedata seeds and oil is discussed. This crop belongs to the family of Cucurbitaceae. Unroasted seeds and oil obtained from roasted seeds were collected during a study trip in Tanzania. Oil from unroasted seeds was extracted in the lab using hexane. The seeds contain approximately 60 (% m/m) of oil and 30 (% m/m) of protein, being the remaining amount represented by crude fiber, carbohydrates and mineral constituents. The protein fraction contains glutamic acid, arginine, aspartic acid and leucine as the most representative amino acids. The fatty acid composition is a common one, being palmitic, linoleic, stearic and oleic acids, the most important fatty acids detected. No difference was found in fatty acid composition between oils extracted from roasted and unroasted seeds. On the contrary, the oil obtained from roasted seeds shows a higher concentration in sterols and tocopherols while the distribution between the different constituents remains the same.

EFFECTS OF ALIPHATIC ALCOHOLS AND FATTY ACIDS ON THE METABOLISM OF ACETATE BY RAT LIVER SLICES

1961 ◽  
Vol 39 (12) ◽  
pp. 1895-1909 ◽  
Author(s):  
E. Majchrowicz ◽  
J. H. Quastel
Keyword(s):  
Fatty Acids ◽  
Rat Liver ◽  
Acid Synthesis ◽  
Aliphatic Alcohols ◽  
Isotopic Dilution ◽  
Acetate Oxidation ◽  
Inhibitory Effects ◽  
Acetyl Coa ◽  
Liver Slices ◽  
Equivalent Quantity

The effects of the addition of normal aliphatic alcohols and fatty acids on the metabolism of acetate by rat liver slices have been investigated, with particular reference to the formation, from acetate-1-C14, of C14O2 and radioactive lipids, proteins, and fatty acids. Whereas the addition of unlabelled acetate causes a fall in the rate of formation of C14O2, the decrease, at low concentrations, is less than that calculated for isotopic dilution. This is probably due to the fact that with an increased concentration of acetate there is an increased rate of acetate oxidation. However, the addition of ethanol causes a larger fall in the rate of formation of C14O2 than would be expected if the alcohol were converted to acetate. This points to some inhibition by ethanol of acetate oxidation, a conclusion borne out by the inhibitory effects of n-alcohols on total CO2 formation (in the absence and in the presence of added acetate) by rat liver slices. The fact, however, that the inhibitory effect of ethanol reaches a maximum at 5 mmolar and is constant to 50 mmolar points against a major inhibition due to ethanol per se. The results would be consistent with the conclusion that ethanol, at low concentrations, is more quickly converted into acetyl-CoA than acetate itself and that its speed of conversion into acetyl-CoA reaches a maximum at about 5 mmolar with rat liver slices. n-Propanol is much more inhibitory than ethanol but its effect is quantitatively identical with that of an equivalent quantity of propionate. Propionate and n-propanol are presumably rapidly converted to propionyl-CoA (or methyl malonyl-CoA), which is the effective inhibitor of acetate oxidation by its competition with acetyl-CoA. Propanol also shows direct inhibitory effects on acetate oxidation in rat liver slices. n-Butanol, n-pentanol, and n-hexanol have inhibitory effects identical with those of equivalent concentrations of corresponding fatty acids. These facts point to the oxidation, in rat liver, of aliphatic alcohols and fatty acids to propionyl-CoA or acetyl-CoA which inhibit C14O2 formation from acetate-1-C14 by competition or isotopic dilution. Alternations of inhibition occur between the odd- and even-numbered carbon alcohols and fatty acids which may be explained by the formation of mixtures of acetyl-CoA and the highly inhibitory propionyl-CoA from the long-chain alcohols and acids. Tribromoethanol is less inhibitory than propanol at equivalent concentrations though it is an effective inhibitor of acetate oxidation. Allyl alcohol is a much more potent inhibitor. Ethanol inhibits incorporation of radioactivity of acetate-1-C14 into fatty acids in rat liver, the inhibition being approximately equal to, or possibly less than, that due to an equivalent quantity of acetate. This may be explained on the basis of isotopic dilution, by acetyl-CoA derived from the alcohol, with radioactive acetyl-CoA undergoing synthesis to radioactive fatty acids. Thus ethanol, at the concentrations investigated, by taking part in fatty acid synthesis, inhibits acetate conversion to fatty acids. Glucose shows the largest effect in stimulating fatty acid synthesis in the liver from acetate, fructose is less effective, and sorbitol shows no effect. The aliphatic alcohols inhibit incorporation of radioactivity from acetate-1-C14 into liver lipids and proteins, propanol and pentanol showing the largest effects. There is an alternation between odd- and even-numbered aliphatic chains. The disappearance, or utilization, of acetate by rat liver slices is inhibited by the aliphatic alcohols, alternations between the odd- and even-numbered chains again being observable. The results are explained as being partly due to isotopic dilution and competition by acetyl-CoA and propionyl-CoA, and partly due to suppressions of acetate metabolism by the alcohols.

scholarly journals KARAKTERISTIK ASAM AMINO DAN ASAM LEMAK BEKASAM KERANG BULU (Anadara antiquate) DI DESA BENAN KABUPATEN LINGGA

Marinade ◽  
2020 ◽  
Vol 3 (02) ◽  
pp. 159-167
Author(s):  
M. Desra Hari Putra ◽  
R. Marwita Sari Putri ◽  
Yulia Oktavia ◽  
Aidil Fadli Ilhamdy
Keyword(s):  
Amino Acids ◽  
Fatty Acids ◽  
Arachidonic Acid ◽  
Fatty Acid ◽  
Amino Acid ◽  
Glutamic Acid ◽  
Linolenic Acid ◽  
Saturated Fatty Acid ◽  
Lauric Acid ◽  
Acid Yield

Formation of feather shells (Anadara antiquata) which has been carried out the characteristics of amino acids and fatty acids obtained the highest amino acid yield is Arginine 10293.28, and the lowest histidine is 136.91. The highest saturated fatty acid is palmitic which is 1.20 and the lowest lauric acid is 0.09, the highest monounsaturated fatty acid is glutamic acid 17257.96, and the lowest is alanine 312.56, the highest polyunsaturated fatty acid is linoleic 0.58, linolenic acid 0.58, and the lowest arachidonic acid 0.29.

scholarly journals THE ESTIMATION OF FATTY ACID SYNTHESIS IN RAT LIVER SLICES

1953 ◽  
Vol 205 (1) ◽  
pp. 401-408
Author(s):  
Grace Medes ◽  
Morris A. Spirtes ◽  
Sidney Weinhouse
Keyword(s):  
Fatty Acid ◽  
Rat Liver ◽  
Fatty Acid Synthesis ◽  
Acid Synthesis ◽  
Liver Slices

Effect of saturated fat diets on rat liver NADP-linked enzymes

1965 ◽  
Vol 209 (4) ◽  
pp. 773-780 ◽  
Author(s):  
Helen M. Tepperman ◽  
Jay Tepperman
Keyword(s):  
Fatty Acids ◽  
Enzyme Activity ◽  
Rat Liver ◽  
Corn Oil ◽  
Saturated Fat ◽  
Coconut Oil ◽  
Liver Slices ◽  
Fat Diets ◽  
Effect Of Feeding

The aggregate hexosemonophosphate dehydrogenase (HMPD) activity was found to be higher in livers of rats fed a diet containing saturated fat (hydrogenated coconut oil = H) for 7 days and fasted for 48 hr than it was in similarly prepared animals fed a corn oil (CO) diet. Later, a liver HMPD-increasing effect of feeding H was found in nonfasted animals. Lipogenesis (i.e., the incorporation of acetate-1-C14 into fatty acids by liver slices) was shown to be as low or lower in the H group as in the CO. Liver slices prepared from H and CO diet adapted rats were incubated with either acetate-1-C14 or palmitate-1-C14 and the extent of incorporation of C14 into individual fatty acids was measured. With both substrates more radioactivity was found in 16:1, 18:0, and 18:1 in the case of H-fed animals. It is proposed that a component of the signal for eliciting increased NADP-linked enzyme activity in the H rats was an increased rate of oxidation of NADPH attendant on monoene formation and chain lengthening.

scholarly journals Utilization in vivo of glucose and volatile fatty acids by sheep brain for the synthesis of acidic amino acids

1966 ◽  
Vol 101 (3) ◽  
pp. 591-597 ◽  
Author(s):  
R M O'Neal ◽  
R E Koeppe ◽  
E I Williams
Keyword(s):  
Amino Acids ◽  
Fatty Acids ◽  
Glutamic Acid ◽  
Aspartic Acid ◽  
Free Amino Acids ◽  
Free Amino ◽  
Specific Activity ◽  
Tricarboxylic Acid Cycle ◽  
Sheep Brain ◽  
The Brain

1. Free glutamic acid, aspartic acid, glutamic acid from glutamine and, in some instances, the glutamic acid from glutathione and the aspartic acid from N-acetyl-aspartic acid were isolated from the brains of sheep and assayed for radioactivity after intravenous injection of [2-(14)C]glucose, [1-(14)C]acetate, [1-(14)C]butyrate or [2-(14)C]propionate. These brain components were also isolated and analysed from rats that had been given [2-(14)C]propionate. The results indicate that, as in rat brain, glucose is by far the best precursor of the free amino acids of sheep brain. 2. Degradation of the glutamate of brain yielded labelling patterns consistent with the proposal that the major route of pyruvate metabolism in brain is via acetyl-CoA, and that the short-chain fatty acids enter the brain without prior metabolism by other tissue and are metabolized in brain via the tricarboxylic acid cycle. 3. When labelled glucose was used as a precursor, glutamate always had a higher specific activity than glutamine; when labelled fatty acids were used, the reverse was true. These findings add support and complexity to the concept of the metabolic; compartmentation' of the free amino acids of brain. 4. The results from experiments with labelled propionate strongly suggest that brain metabolizes propionate via succinate and that this metabolic route may be a limited but important source of dicarboxylic acids in the brain.

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