Search results for "linoleic acid"
showing 10 items of 147 documents
Inhibition of fatty acid delta 6- and delta 5-desaturation by cyclopropene fatty acids in rat liver microsomes.
1993
delta 6-Desaturation of linoleic acid and delta 5-desaturation of dihomo-gamma-linolenic acid were measured in liver microsomes from rats fed fresh Baobab seed oil containing cyclopropene fatty acids (malvalic acid and sterculic acid) or heated Baobab seed oil practically devoid of these fatty acids or control oil. The presence of cyclopropene fatty acids in the fresh Baobab oil diet highly depressed both desaturations, but delta 6- more than delta 5-desaturation. The decreased capacity of microsomes to desaturate was reflected in the lower arachidonic acid content in microsomal phospholipids from rats fed this oil. However it was also lower in rats fed heated oil although in vitro delta 6-…
Silver ion chromatography and gas chromatography-mass spectrometry in the structural analysis of cyclic dienoic acids formed in frying oils
1995
The nature of the cyclic monoenoic fatty acids formed from linoleic acid in sunflower oil heated to 275°C has been determined by gas chromatography-mass spectrometry of the picolinyl ester derivatives, before and after hydrogenation and deuteration, and following simplification by silver ion high-performance liquid chromatography. In addition, they were examined by gas chromatography-Fourier transform infrared spectroscopy. Cyclopentene fatty acids (50% of the total monoenes) were formed from C-8 to C-12 and C-10 to C-14 of the original chain in equal amounts with unique stereochemistry. In some isomers the double bond appeared to remain in its original position, and in others it migrated t…
CLA-Enriched Diet Containing t10,c12-CLA Alters Bile Acid Homeostasis and Increases the Risk of Cholelithiasis in Mice
2011
International audience; Mice fed a mixture of CLA containing t10,c12-CLA lose fat mass and develop hyperinsulinemia and hepatic steatosis due to an accumulation of TG and cholesterol. Because cholesterol is the precursor in bile acid (BA) synthesis, we investigated whether t10,c12-CLA alters BA metabolism. In Expt. 1, female C57Bl/6J mice were fed a standard diet for 28 d supplemented with a CLA mixture (1 g/100 g) or not (controls). In Expt. 2, the feeding period was reduced to 4, 6, and 10 d. In Expt. 3, mice were fed a diet supplemented with linoleic acid, c9,t11-CLA, or t10,c12-CLA (0.4 g/100 g) for 28 d. In Expt. 1, the BA pool size was greater in CLA-fed mice than in controls and the …
Chemical composition of lipophilic extractives from grey alder (Alnus incana)
2013
The chemical composition of the lipophilic extractives in the hexane extracts from grey alder bark, knotwood, and cones has been investigated by gas chromatography and gas chromatography-mass spectrometry. The efficiency of two extraction methods was compared. The highest amount of lipophilic extractives (about 9% of o.d. material) was observed in grey alder cone, while the lowest (about 3%) was found in knotwood. The three different morphological parts of alder showed significant differences not only in the content but also in composition of extractives, namely fatty acids, triglycerides, and triterpenes. The main identified compounds were triterpenoids (lupen-3-one, lupeol, betulone, betu…
Fatty Acid Composition of Salami Made by Meat from Different Commercial Categories of Indigenous Dairy Cattle
2021
Simple Summary The Cinisara is a Sicilian breed raised on pasture to produce the Caciocavallo Palermitano cheese. Even if it is penalized by competition with meat breeds, characterized by higher growth rate and yield, the production of fresh meat represents a considerable added value for the smallfarms. The meat of Cinisara is not appreciated, despite having a high content of iron, vitamin E, conjugated linoleic acid (CLA), and low content of lipids and cholesterol, above all due to incorrect management of the supply chain phases that negatively affects the quality of the final product. Alternative production such as bresaola and salami could contribute to the enhancement of Cinisara meat. …
Effect of a 2-y dietary and physical activity intervention on plasma fatty acid composition and estimated desaturase and elongase activities in child…
2016
Background: Evidence on the effects of lifestyle interventions on plasma fatty acid composition in children is limited. Objective: We investigated the effects of a dietary and physical activity intervention on plasma fatty acid composition of cholesteryl esters (CEs) and phospholipids and estimated desaturase and elongase activities in children. Design: We conducted a 2-y controlled dietary and physical activity intervention based on Finnish nutrition and physical activity recommendations in a population sample of 506 children aged 6–8 y. We assessed plasma fatty acid composition by gas chromatography and estimated desaturase and elongase activities as the ratio of product fatty acids to pr…
Age-related changes in delta 6 and delta 5 desaturase activities in rat liver microsomes.
1993
Age-related changes in Δ6 desaturation of [1-14C]α-linolenic acid and [1-14C]linoleic acid and in Δ5 desaturation of [2-14C]dihomo-γ-linolenic acid were studied in liver microsomes from Wistar male rats at various ages ranging from 1.5 to 24 mon. Desaturase activities were expressed both as specific activity of liver microsomes and as the capacity of whole liver to desaturate by taking into account the total amount of liver microsomal protein. Δ6 Desaturation of α-linolenic acid increased from 1.5 to 3 mon and then decreased linearly up to 24 mon to reach the same desaturation capacity of liver measured at 1.5 mon. The capacity of liver to desaturate linoleic acid increased up to 6 mon and …
Effect of ethanol on polyunsaturated fatty acid biosynthesis in hepatocytes from spontaneously hypertensive rats.
2001
Background: Polyunsaturated fatty acids (PUFA) play a major role in membrane structures that are modified during alcoholism. PUFA are also precursors of second messengers—eicosanoids—involved in the regulation of blood pressure. Alcohol has been related to hypertension and to alterations in liver PUFA metabolism. We investigated the effects of ethanol on PUFA biogenesis in hepatocytes of Wistar Kyoto (WKY) rats and Spontaneously Hypertensive Rats (SHR). The effects of a diet enriched with n-3 PUFA, which is known to modulate hypertension, were also studied. Methods: Isolated hepatocytes from male normotensive Wistar Kyoto (WKY) rats and SHR were incubated for 60 min in the presence of label…
Effect of Salt-Loading and Spontaneous Hypertension on in Vitro Metabolism of [1-14C]Linoleic and [2-14C]Dihomo-γ-linolenic Acids
1993
The present study compared the effect of spontaneous hypertension and salt-loading on in vitro metabolism of 18:2n-6 (linoleic acid) and 20:3n-6 (dihomo-gamma-linolenic acid). Ten weanling spontaneously hypertensive rats (SHR) and 10 normotensive Wistar-Kyoto rats (WKY) maintained on a rodent lab chow were given tap water with (n = 5) or without (n = 5) addition of 1% NaCl for 4 weeks. Thereafter, animals were killed and liver microsomes were prepared. Aliquots of microsomes suspended in the phosphate-sucrose buffer containing MgCl2, ATP, CoA, and NADPH were incubated with 0.3 microCi of [1-14C]-18:2n-6 or [2-14C]-20:3n-6 at 37 degrees C for 15 min. The activity of delta 6- and delta 5-desa…
Effect of sodium loading (3% NaCl) on arachidonic acid biosynthesis in rat liver microsomes
1992
Sodium loading increases arachidonic acid (AA) metabolism by way of the prostaglandins(PGs) from series 2. Its effect on AA biosynthesis remains unknown. The purpose of the present study was to investigate the influence of sodium loading on the fatty acid composition of liver and liver microsomes, and the liver microsomal delta-6 and delta-5 desaturations of linoleic acid (LA) into AA. We found a decrease of LA and dihomo-gamma-linolenic acid (DGLA) levels in liver total lipids of Wistar rats receiving hypernatriuretic drinking water (NaCl 3%) for 60 days. At the same time AA increased. DGLA decreased and AA increased in liver microsomal total lipids. 1(14) C-LA delta-6 desaturase and 2(14)…