scholarly journals Synthesis of fatty acids from [1-14C]acetylcoenzyme A in subcellular particles of rat epididymal adipose tissue

1972 ◽  
Vol 128 (4) ◽  
pp. 847-857 ◽  
Author(s):  
H. Kanoh ◽  
D. B. Lindsay

1. Mitochondrial and microsomal fractions of rat epididymal adipose tissue incorporated [1-14C]acetyl-CoA equally well into various fatty acids by a chain-elongation mechanism. C18 and C20 fatty acids were the two major products, and comprised about 80% of the total fatty acids synthesized in both particles. 2. When incubated in air, mitochondria synthesized stearic acid, octadecenoic acid and eicosamonoenoic acid in almost equal amounts (about 20% each), whereas in microsomal fractions, the synthesis of octadecenoic acid was more than fivefold the stearic acid formation. In both fractions, major components of synthesized monoenoic fatty acids were the Δ11:12 isomers. Hexadecenoic acid and octadecenoic acid from whole adipose tissue contained approx. 11 and 14% of the Δ11:12 isomer respectively. 3. When mitochondria or microsomal fractions were incubated in nitrogen, there was increased synthesis of stearic acid and palmitic acid and less of C16 and C18 monoenoic acids; synthesis of C20 acids remained predominantly of the monoenoic acids. Determination of the position of the double bond in the monoenoic acids supported the view that the synthesis of hexadecenoic acid and octadecenoic acid involves a desaturase activity, whereas eicosamonoenoic acid and eicosadienoic acid are formed only by elongation of endogenous fatty acids. 4. Most of the radioactivity was found in free fatty acids (63%) and the phospholipid (26%) fraction. In phospholipids, phosphatidylcholine and phosphatidylethanolamine were the two major components. 5. Most of the fatty acids synthesized, including those not normally found in particle lipids (arachidic acid, eicosamonoenoic acid and eicosadienoic acid) were distributed fairly evenly in the phospholipid and free fatty acid fractions. However, stearic acid was found predominantly in the phospholipid fraction.

1977 ◽  
Vol 89 (3) ◽  
pp. 575-582 ◽  
Author(s):  
W. M. F. Leat

SummaryAberdeen Angus and Friesian cattle were reared from 4 months of age to slaughter weight at 18–24 months on either high-barley or high-hay diets. Samples of subcutaneous fat were taken by biopsy at 3 monthly intervals, and the degree of fatness of each animal was estimated ultrasonically prior to slaughter, and by visual inspection of the carcasses.The barley-fed animals gained weight more rapidly, and fattened more quickly than the hay-fed animals with the Angus being fatter than the Friesian at the same age. The percentage stearic acid (C18:0) in subcutaneous fat decreased with age and was replaced by octadecenoic acid (C18:l) and hexadecenoic acid (C16:l), these changes being more rapid in barley-fed than in hay-fed animals. At the same degree of fatness the depot fats of the Friesians were more unsaturated than those of the Angus, and in both breeds the fatter the animal the more unsaturated was its depot fat.In the hay-fed cattle the percentage C16:0 in subcutaneous fat increased during the last half of the experiment and at slaughter the percentage C16:0 was significantly higher, and C18:l significantly lower, in all depot fats compared with those of the barley-fed animals.It is concluded that the fatty acid composition of bovine depot fats is modulated by the degree of fattening, and can be affected by diet.


1960 ◽  
Vol 38 (6) ◽  
pp. 805-812 ◽  
Author(s):  
Mary J. Chisholm ◽  
C. Y. Hopkins

The seed oil of Asclepiassyriaca L., family Asclepidaceae, was examined by gas chromatography and distillation of the methyl esters. The fatty acids were found to include a considerable proportion of cis-11-octadecenoic acid, which has not been observed previously in seed oils. It was obtained as a concentrate [Formula: see text] by low-temperature crystallization of the C18 acids and identified as 11,12-dihydroxystearic acid. The amount of 11-octadecenoic acid in the oil was determined by oxidative splitting of the total fatty acids and estimation of the resulting azelaic and undecanedioic acids by gas chromatography.The C16 acids included 9,12-hexadecadienoic acid, which is rare in seed oils,and an unusually large proportion of 9-hexadecenoic acid. The percentage composition of the fatty acids was estimated from the data as follows: palmitic 4,9-hexadecenoic 10, 9,12-hexadecadienoic 2, stearic < 1, oleic 15, 11-octadecenoic 15, linoleic 53, linolenic < 1. The unsaturated acids have the cis configuration.


1994 ◽  
Vol 40 (10) ◽  
pp. 844-850 ◽  
Author(s):  
Peter Kämpfer ◽  
Klaus Blasczyk ◽  
Georg Auling

A chemotaxonomic study was carried out on representative strains of 13 Aeromonas genomic species. Quinone, polyamine, and fatty acid patterns were found to be very useful for an improved characterization of the genus and an improved differentiation from members of the families Enterobacteriaceae and Vibrionaceae. The Q-8-benzoquinone was the predominant ubiquinone, and putrescine and diaminopropane were the major poly amines of the genus. The fatty acid patterns of 181 strains, all characterized by DNA–DNA hybridization, showed a great homogeneity within the genus, with major amounts of hexadecanoic acid (16:0), hexadecenoic acid (16:1), and octadecenoic acid (18:1), and minor amounts of the hydroxylated fatty acids (3-OH 13:0, 2-OH 14:0, 3-OH 14:0) in addition to some iso and anteiso branched fatty acids (i-13:0, i-17:1, i-17:0, and a-17:0). Although some differences in fatty acid profiles between the genomic species could be observed, a clearcut differentiation of all species was not possible.Key words: Aeromonas, polyamines, quinones, fatty acids, differentiation.


2002 ◽  
Vol 2002 ◽  
pp. 206-206 ◽  
Author(s):  
Z.C.T.R. Daniel ◽  
R.J. Wynn ◽  
A.M. Salter ◽  
P.J. Buttery

Compared to meat from other animals lamb contains high levels of saturated fat, particularly stearic acid which comprises 18% of the total fatty acids (Enser et al, 1996). This stearic acid can be desaturated in the tissue by stearoyl coenzyme A desaturase (SCD) to produce oleic acid. In sheep SCD is produced from a single gene and the levels of SCD mRNA in the tissue correlate well with oleic acid (Ward et al, 1998, Barber et al, 2000) suggesting that an upregulation of SCD activity may increase the relative proportions of unsaturated and saturated fatty acids and so significantly improve the nutritional quality of sheep meat. Our recent studies have shown that insulin increases SCD mRNA levels and monounsaturated fatty acid synthesis in cultured ovine adipose tissue explants (Daniel et al, 2001). The present study was designed to investigate whether feeding a diet believed to manipulate SCD mRNA concentrations would significantly alter the fatty acid composition of lamb.


2012 ◽  
Vol 7 (10) ◽  
pp. 1934578X1200701 ◽  
Author(s):  
Rashmi Kumari ◽  
Gopal Rao Mallavarapu ◽  
Vinod Kumar Jain ◽  
Sushil Kumar

Fatty oils of the seeds of Cleome viscosa accessions from Delhi, Jaipur, Faridabad, Surajkund and Hyderabad were methylated and analyzed by GC and GC-MS. The major fatty acids, identified as their methyl esters, of the oils from these five locations were palmitic acid (10.2-13.4%), stearic acid (7.2-10.2%), oleic acid (16.9-27.1%) and linoleic acid (47.0-61.1%). In addition, palmitoleic acid, octadec-(11 E)-enoicacid, arachidic acid, eicosa-(11 Z)-enoic acid, linolenic acid, heneicosanoic acid, behenic acid, lignoceric acid, pentacosanoic acid, hexacosanoic acid, 12-oxo-stearic acid, and the alkanes tetracosane, pentacosane, hexacosane, heptacosane, octacosane, nonacosane, triocontane, hentriacontane and dotriacontane, were also identified as minor and trace constituents in some of these oils.


1963 ◽  
Vol 205 (4) ◽  
pp. 702-706 ◽  
Author(s):  
Alisa Gutman ◽  
Eleazar Shafrir

Epididymal adipose tissue of aminonucleoside-treated rats, investigated 3 to 6 days after induction of the nephrotic syndrome, had low glycogen levels and showed impaired esterification of free fatty acids and assimilation of lipoprotein triglyceride and markedly reduced liberation of lipoprotein lipase. These results were found to be influenced by the inadequate food intake of the acutely nephrotic animals and comparable to the values of control rats fasted for 2 days. On return to adequate nutrition, which occurred 12–20 days after aminonucleoside treatment, adipose tissue glycogen and free fatty acid assimilation returned toward normal levels but lipoprotein-lipase liberation remained below normal. In rats rendered nephrotic by antikidney serum, the assimilation of free fatty acids and lipoprotein-triglyceride by adipose tissue was impaired in spite of only minor reduction in food consumption. The results indicate that the defective metabolism of adipose tissue in nephrotic animals may be contributory to the nephrotic hypertriglyceridemia.


1963 ◽  
Vol 41 (1) ◽  
pp. 269-273 ◽  
Author(s):  
D. D. Feller ◽  
E. Feist

Epididymal adipose tissue was incubated with uniformly labelled (14C)-methionine, (2-14C)-methionine, and uniformly labelled (14C)-threonine. Each of these compounds is actively metabolized by adipose tissue, as evidenced by the generation of 14CO2 and (14C)-fatty acid. Evidence was gathered in regard to the intermediary pathways by which these amino acids are utilized by adipose tissue and the general conclusion is drawn that these pathways are similar to those postulated for other tissues. These experiments further emphasize the central role that propionate plays in adipose tissue lipogenesis.


1969 ◽  
Vol 23 (2) ◽  
pp. 421-427 ◽  
Author(s):  
G. A. Garton ◽  
W. R. H. Duncan

1. Samples of subcutaneous (inguinal) and perinephric adipose tissue were obtained, at slaughter, from each of twenty male calves. Three were neonatal animals, three were 3 days old and two were fed on reconstituted milk to appetite until they weighed 100 kg. The other twelve calves were given milk until they reached 50 kg live weight; concentrates were then included in the diet until, at 60 kg live weight, six calves were slaughtered. The remaining six calves were raised to 100 kg on concentrates alone. The weight of the empty reticulo-rumen of each slaughtered calf was recorded.2. The component fatty acids of the adipose tissue triglycerides of the neonatal and 3-day-old calves were very similar; about 80% consisted of oleic acid (18:1) and palmitic acid (16:0) and the remainder comprised stearic acid (18:0), palmitoleic acid (16:1) and myristic acid (14:0), together with very small amounts of other acids which, in the glycerides of the 3-day-old calves, included some evidently of colostral origin. The perinephric glycerides of both these groups of calves were somewhat more unsaturated than were those of subcutaneous adipose tissue.3. The continued consumption of milk by the calves slaughtered at 60 kg live weight was reflected in the presence of enhanced proportions of 14:0, 18:2, 17:0 and 17:1 in the depot triglycerides and, in addition, very small amounts of branched-chain acids and trans 18:1 were detected. A similar fatty acid pattern was observed in the triglycerides of the calves which were given milk only until they were 100 kg live weight. In all these calves only limited growth of the rumen took place.4. By contrast, the calves which were raised on solid feed from 60 kg to 100 kg and in which rumen development had taken place had depot triglycerides whose fatty acid composition resembled that found in adult animals. Increased proportions of stearic acid accompanied by relatively large amounts of trans 18:1 were present, evidently as a result of the assimilation of the products of bacterial modification of dietary fatty acids in the rumen.5. Regardless of the age of the calves and the over-all fatty acid composition of their tissue triglycerides, the intramolecular disposition of the fatty acids was similar in that saturated components were present esterified mainly in positions 1 and 3, and unsaturated acids for the most part in position 2; the only major exception to this distribution pattern was in respect of trans 18:1 which, when present, was preferentially esterified to the primary alcoholic groups of the glycerol moiety as if it were a saturated acid.


1966 ◽  
Vol 44 (1) ◽  
pp. 47-57 ◽  
Author(s):  
James Campbell ◽  
G. R. Green

In normal Chinese hamsters (Cricetulus griseus) the mean concentration of free fatty acids (FFA) in serum varied from group to group, but was (i) consistently 4 to 9 times greater than in rats, dogs, or man; (ii) slightly higher than in Syrian hamsters; (iii) two- to four-fold higher than in fasting or alloxan-diabetic rats. The epididymal adipose tissue of the Chinese hamster (i) had initial concentrations of FFA comparable to those in the rat and Syrian hamster; (ii) released, in the same time interval, 8- to 10-fold more FFA in vitro than this tissue of the rat; (iii) had higher concentrations of FFA after incubation than the incubated tissue of the rat. The retroperitoneal (perirenal) adipose tissue of the Chinese hamster was less active in release of fatty acids in vitro than the epididymal, but was, however, more active than the epididymal adipose tissue of the rat. These characteristics of FFA metabolism in the Chinese hamster were apparently attributable to species, not to age, diet, or sex. In the Chinese hamster, the weight of the epididymal adipose tissue per gram of body was relatively high. It appears that in this species the rate of release of fatty acids from adipose tissue is great, leading to high FFA concentrations in serum.In Chinese hamster and rat adipose tissues in vitro, glucose and insulin (separately) reduced the rate of release of FFA and the amount of FFA in the tissues, but glucose and insulin together produced the greatest reductions. The net reduction in FFA release by glucose and insulin in vitro was greater in tissue from the Chinese hamster. Insulin markedly increased glucose uptake by the adipose tissues of both species. The possible relation of the results to spontaneous diabetes in the Chinese hamster is discussed.


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