INVESTIGATIONS INTO THE PRODUCTION OF LIPIDS BY SUBMERGED CULTURES OF THE MUSHROOM TRICHOLOMA NUDUM: II. STUDIES WITH UNIFORMLY LABELLED GLUCOSE

1962 ◽  
Vol 40 (7) ◽  
pp. 857-867 ◽  
Author(s):  
D. C. Leegwater ◽  
B. M. Craig

Tricholoma nudum mycelium, grown in a medium with a low nitrogen content, was adapted to a basal medium containing glucose and incubated with glucose-U-C14for 25 hours. The time – specific activity relations of the major fatty acids produced were determined for both the neutral lipids and the phospholipids. The results confirm a previous finding that in the phospholipids of T. nudum linoleic acid becomes labelled under the conditions used at almost the same rate as palmitic, stearic, or oleic acid, but that in the neutral lipids the specific activity of this acid initially lags considerably behind those of the latter three. It is postulated that this phenomenon is due to a difference in the relative sizes of the linoleic acid pools involved in the synthesis of the two lipid fractions. Only part of the material used for the formation of the fatty acids is derived directly from the substrate, the remainder apparently being provided by material already present in the mycelium. The various results, together with those of earlier workers, are critically evaluated, and it is concluded that the order in which fatty acids are labelled in tracer studies with intact cells is determined to a large extent by the conditions of the experiment and does not necessarily provide information on possible product–precursor relations.

1962 ◽  
Vol 40 (1) ◽  
pp. 857-867 ◽  
Author(s):  
D. C. Leegwater ◽  
B. M. Craig

Tricholoma nudum mycelium, grown in a medium with a low nitrogen content, was adapted to a basal medium containing glucose and incubated with glucose-U-C14for 25 hours. The time – specific activity relations of the major fatty acids produced were determined for both the neutral lipids and the phospholipids. The results confirm a previous finding that in the phospholipids of T. nudum linoleic acid becomes labelled under the conditions used at almost the same rate as palmitic, stearic, or oleic acid, but that in the neutral lipids the specific activity of this acid initially lags considerably behind those of the latter three. It is postulated that this phenomenon is due to a difference in the relative sizes of the linoleic acid pools involved in the synthesis of the two lipid fractions. Only part of the material used for the formation of the fatty acids is derived directly from the substrate, the remainder apparently being provided by material already present in the mycelium. The various results, together with those of earlier workers, are critically evaluated, and it is concluded that the order in which fatty acids are labelled in tracer studies with intact cells is determined to a large extent by the conditions of the experiment and does not necessarily provide information on possible product–precursor relations.


1962 ◽  
Vol 40 (7) ◽  
pp. 847-855 ◽  
Author(s):  
D. C. Leegwater ◽  
C. G. Youngs ◽  
J. F. T. Spencer ◽  
B. M. Craig

The production of neutral lipids and phospholipids by submerged cultures of the mushroom Tricholoma nudum, as well as the fatty acid composition of these two fractions, was studied as a function of time. The bulk of the neutral lipids was produced after 2 days when the organism appeared to be in a non-proliferative phase. The major fatty acids of the neutral lipids were palmitic, oleic, and linoleic acid (23–35% each); stearic acid was a minor component (8–13%); myristic, palmitoleic, and linolenic acid were present in small amounts (0.5–4.8%). The major fatty acid of the phospholipids was linoleic acid (55–70%); palmitic (15–19%), stearic (1.8–4.6%), and oleic (7–19%) acid were minor components; myristic, palmitoleic, and linolenic (0–2.3%) were present in small amounts. Linolenic acid was a major fatty acid (26–30%) only in the early stages of growth.A preliminary investigation was carried out with a 4-day-old culture to establish the identity of the various components of the neutral lipids and phospholipids. The neutral lipids were mainly triglycerides (92%). Small amounts of ergosterol esters (1%), free fatty acids (< 1%), ergosterol (1.7%), and unidentified non-saponifiable compounds were also present. The phospholipids contained phosphatidyl choline (59%) as the major component; phosphatidyl ethanolamine (26%), phosphatidyl serine and phosphatidic acid (7.8%), and an inositol containing phospholipid were minor components.Some of the techniques applied were specially developed for the present type of studies and are described in detail.


1962 ◽  
Vol 40 (1) ◽  
pp. 847-855 ◽  
Author(s):  
D. C. Leegwater ◽  
C. G. Youngs ◽  
J. F. T. Spencer ◽  
B. M. Craig

The production of neutral lipids and phospholipids by submerged cultures of the mushroom Tricholoma nudum, as well as the fatty acid composition of these two fractions, was studied as a function of time. The bulk of the neutral lipids was produced after 2 days when the organism appeared to be in a non-proliferative phase. The major fatty acids of the neutral lipids were palmitic, oleic, and linoleic acid (23–35% each); stearic acid was a minor component (8–13%); myristic, palmitoleic, and linolenic acid were present in small amounts (0.5–4.8%). The major fatty acid of the phospholipids was linoleic acid (55–70%); palmitic (15–19%), stearic (1.8–4.6%), and oleic (7–19%) acid were minor components; myristic, palmitoleic, and linolenic (0–2.3%) were present in small amounts. Linolenic acid was a major fatty acid (26–30%) only in the early stages of growth.A preliminary investigation was carried out with a 4-day-old culture to establish the identity of the various components of the neutral lipids and phospholipids. The neutral lipids were mainly triglycerides (92%). Small amounts of ergosterol esters (1%), free fatty acids (< 1%), ergosterol (1.7%), and unidentified non-saponifiable compounds were also present. The phospholipids contained phosphatidyl choline (59%) as the major component; phosphatidyl ethanolamine (26%), phosphatidyl serine and phosphatidic acid (7.8%), and an inositol containing phospholipid were minor components.Some of the techniques applied were specially developed for the present type of studies and are described in detail.


Author(s):  
Lena Oksdøl Foseid ◽  
Hanne Devle ◽  
Yngve Stenstrøm ◽  
Carl Fredrik Naess-Andresen ◽  
Dag Ekeberg

A thorough analysis and comparison of the fatty acid profiles of stipe and blade from Laminaria hyperborea, a kelp species found in the northern Atlantic, is presented. Lipids were extracted and fractionated into neutral lipids, free fatty acids and polar lipids, then derivatized to fatty acid methyl esters prior to GC-MS analysis. A total of 42 fatty acids were identified and quantified, including the n-3 fatty acids &alpha;-linolenic acid, stearidonic acid and eicosapentaenoic acid. An n-6/n-3 ratio of 0.8:1 was found in blade and 3.5:1 in stipe, respectively. The ratios vary between the lipid fractions within stipe and blade, with the lowest ratio in the polar lipid fraction of blade. The fatty acid amounts are higher in blade than in stipe, and the highest amounts of n-3 fatty acids are found within the neutral lipid fractions. The amounts of polyunsaturated fatty acids are 3.4 times higher in blade than stipe. This study highlights the compositional differences between the lipid fractions of stipe and blade from L. hyperborea. The amount of polyunsaturated fatty acids, compared to saturated- and monounsaturated fatty acids, as well as the n-6/n-3-ratio, is known to influence human health. In the pharmaceutical, food, and feed industries this can be of importance for production and sale of different health products. Additionally, lipids are today among the unused by products of alginate production, exploiting this material for commercial interest should give both economical and environmental benefits.


1956 ◽  
Vol 34 (3) ◽  
pp. 429-440 ◽  
Author(s):  
Dorothy L. Kline ◽  
H. A. DeLuca

A study has been made of the labelling of the phospholipids, the fatty acids from the acetone-soluble lipid, and the non-esterified cholesterol in slices of rat and guinea pig liver respiring in a suitably buffered Krebs–Ringer medium containing acetate-1-C14. The time course of the reactions and the effects of the concentration of potassium ion and the pH of the incubating medium have been defined. For phospholipid and fatty acids of the acetone-soluble lipid, the optimum pH was in the range 6.8–7.4, whereas for cholesterol there was a much sharper optimum at pH 6.6–6.8. When the oxygen of the gas phase was replaced with nitrogen, the labelling of all three lipid fractions was abolished. The addition of glucose to the incubating medium slightly increased the labelling of the phospholipids and the fatty acids of the acetone-soluble lipid, but had no consistent effect on the labelling of the non-esterified cholesterol. Purification of the cholesterol by the method of bromination and debromination caused only a slight change in specific activity, indicating that the cholesterol was not contaminated with large amounts of companion substances with specific activities greatly different from that of the cholesterol itself. The addition of cyanide, fluoride, iodoacetate, or 2,4-dinitrophenol to the incubating medium caused a great decrease in the labelling of all fractions studied. With the exception of 2,4-dinitrophenol, the inhibitors were used in concentrations that inhibit the oxygen consumption. Malonate inhibited the incorporation of acetate-1-C14 into cholesterol, but did not affect the labelling of the phospholipids. When the acetate-1-C14 was replaced with other C14-labelled precursors, good labelling of phospholipids was observed with glycine-2-C14, glycerol-1-C14, and fructose-C11, but not with formate-C14, lactate-1-C14, or glucose-C14. The cholesterol was not significantly labelled from any of the precursors other than acetate-1-C14.


1978 ◽  
Vol 234 (6) ◽  
pp. E593 ◽  
Author(s):  
T A Kotchen ◽  
W J Welch ◽  
R T Talwalkar

Circulating neutral lipids inhibit the in vitro renin reaction. To identify the inhibitor(s), free fatty acids were added to human renin and homologous substrate. Capric, lauric, palmitoleic, linoleic, and arachidonic acids each inhibited the rate of angiotensin I production in vitro (P less than 0.01). Inhibition by polysaturated fatty acids (linoleic and arachidonic) was less (P less than 0.01) after catalytic hydrogenation of the double bonds. To evaluate an in vivo effect of renin inhibition intra-arterial blood pressure responses to infusions of renin and angiotensin II (5.0 microgram) were measured in anephric rats (n = 6) before and after infusion of linoleic acid (10 mg iv). Mean increase of blood pressure to angiotensin II before (75 mmHg +/- 9) and after (90 +/- 12) linoleic acid did not differ (P greater than 0.05). However, the pressor response to renin after linoleic acid (18 +/- 3) was less (P less than 0.00)) than that before (102 +/- 13). In summary, several fatty acids inhibit the in vitro renin reaction, and in part inhibition is dependent on unsaturation. Linoleic acid also inhibits the in vivo pressor response to renin. These results suggest that fatty acids may modify the measurement of plasma renin activity and may also affect angiotensin production in vivo.


1966 ◽  
Vol 20 (3) ◽  
pp. 553-559 ◽  
Author(s):  
E. P. M. Bhattathiry

1. A comparative study was undertaken with rats on the effect of various diets (normal stock, fat-free, palm oil and olive oil) on the in vitro incorporation of [14C]acetate by the liver into cholesterol and into the fatty acids of phospholipids and neutral fats. 2. The total lipids extracted from the incubation mixtures were fractionated into acetone-precipitable and digi- tonin-precipitable portions and also into the fatty acids of neutral lipids. 3. The incorporation of [14C]acetate into the acetone-precipitable fraction and into fatty acids of neutral fats was greatest in livers of rats given the fat-free diet, followed by those of the groups given olive oil, the normal stock diet, and palm oil. Livers from the group given the fat-free diet also exhibited the highest percentage of 14C activity in the digitonin-precipitable fraction and were closely followed by the group on the normal stock diet. Compared with those of the other two groups, the livers of the groups given olive oil and palm oil showed much less activity in the digitonin- precipitable fraction. 4. The greater the amount of a specific type of fatty acid in the diet, the less was the 14C activity incorporated into that type of fattyacid in the ncutral fats of liver slices, hut this was not so with the fatty acids obtained froin the acetone-precipitahlc fraction of the lipids.


2009 ◽  
Vol 297 (2) ◽  
pp. E271-E288 ◽  
Author(s):  
Hong Wang ◽  
Robert H. Eckel

Lipoprotein lipase (LPL) is a multifunctional enzyme produced by many tissues, including adipose tissue, cardiac and skeletal muscle, islets, and macrophages. LPL is the rate-limiting enzyme for the hydrolysis of the triglyceride (TG) core of circulating TG-rich lipoproteins, chylomicrons, and very low-density lipoproteins (VLDL). LPL-catalyzed reaction products, fatty acids, and monoacylglycerol are in part taken up by the tissues locally and processed differentially; e.g., they are stored as neutral lipids in adipose tissue, oxidized, or stored in skeletal and cardiac muscle or as cholesteryl ester and TG in macrophages. LPL is regulated at transcriptional, posttranscriptional, and posttranslational levels in a tissue-specific manner. Nutrient states and hormonal levels all have divergent effects on the regulation of LPL, and a variety of proteins that interact with LPL to regulate its tissue-specific activity have also been identified. To examine this divergent regulation further, transgenic and knockout murine models of tissue-specific LPL expression have been developed. Mice with overexpression of LPL in skeletal muscle accumulate TG in muscle, develop insulin resistance, are protected from excessive weight gain, and increase their metabolic rate in the cold. Mice with LPL deletion in skeletal muscle have reduced TG accumulation and increased insulin action on glucose transport in muscle. Ultimately, this leads to increased lipid partitioning to other tissues, insulin resistance, and obesity. Mice with LPL deletion in the heart develop hypertriglyceridemia and cardiac dysfunction. The fact that the heart depends increasingly on glucose implies that free fatty acids are not a sufficient fuel for optimal cardiac function. Overall, LPL is a fascinating enzyme that contributes in a pronounced way to normal lipoprotein metabolism, tissue-specific substrate delivery and utilization, and the many aspects of obesity and other metabolic disorders that relate to energy balance, insulin action, and body weight regulation.


2020 ◽  
Vol 32 (6) ◽  
pp. 4251-4262
Author(s):  
Lena Foseid ◽  
Ingeborg Natvik ◽  
Hanne Devle ◽  
Dag Ekeberg

AbstractThe fatty acid profiles of the three lipid fractions, neutral lipids (NL), free fatty acids and polar lipids (PL), from the macroalgae Palmaria palmata (wild), Alaria esculenta (cultivated) and Saccharina latissima (cultivated) were studied in light of dietary important fatty acids. Blade and stipe from the macroalgae were collected at the end of the growth season (May/June) at Frøya (Trøndelag, Norway). A total of 51 fatty acids were identified in the algae, including several fatty acids novel to one or more of the algae. The NL and PL fractions of P. palmata were the most promising from a health perspective, due to a high content of eicosapentaenoic acid (10.1 ± 0.5% and 6.6 ± 0.1%, respectively) and no trans-fatty acids. In addition, these fractions had very low omega-6/omega-3 ratios (< 0.1) and can therefore be beneficial for balancing the omega-6/omega-3 ratio in the diet. The NL fraction of A. esculenta had the highest content of monounsaturated- and polyunsaturated fatty acids (20.9 ± 1.4 and 21.8 ± 1.9% of alga, respectively), as well as the highest content of the two essential fatty acids, linoleic acid (5.3 ± 0.4% of alga) and alpha-linolenic acid (2.4 ± 0.2% of alga). Indices related to risk factors for coronary heart disease were most favourable in the NL fraction of S. latissima and the NL and PL fractions of A. esculenta.


2011 ◽  
Vol 31 (3) ◽  
pp. 246-254 ◽  
Author(s):  
Susana V. Martins ◽  
Paula A. Lopes ◽  
Susana P. Alves ◽  
Cristina M. Alfaia ◽  
Mafalda Nascimento ◽  
...  

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