Search results for "FATTY ACID"

2004

β-oxidation of long and very long chain fatty acyl-CoA derivatives occurs in peroxisomes, which are ubiquitous subcellular organelles of eukaryotic cells. This pathway releases acetyl-CoA as precursor for several key molecules such as cholesterol. Numerous enzymes participating to cholesterol and fatty acids biosynthesis pathways are co-localized in peroxisomes and some of their encoding genes are known as targets of the NFY transcriptional regulator. However, until now no interaction between NFY transcription factor and genes encoding peroxisomal β-oxidation has been reported. This work studied the interactions between NFY factor with the rat gene promoters of two enzymes of the fatty acid…

Genetic-dependency of peroxisomal cell functions - emerging aspects

2003

This paper reviews aspects concerning the genetic regulation of the expression of the well studied peroxisomal genes including those of fatty acid beta-oxidation enzymes; acyl-CoA oxidase, multifunctional enzyme and thiolase from different tissues and species. An important statement is PPARalpha, which is now long known to be in rodents the key nuclear receptor orchestrating liver peroxisome proliferation and enhanced peroxisomal beta-oxidation, does not appear to control so strongly in man the expression of genes involved in peroxisomal fatty acid beta-oxidation related enzymes. In this respect, the present review strengthens among others the emerging concept that, in the humans, the main …

Fatty Acid Aggregates Simulated using Constant pH Molecular Dynamics with a Coarse-Grained Model

2013

Fatty acids are crucial biomolecules, important for lipid metabolism, signaling, models for protocell membranes, soaps, industrial applications, and drug delivery. Oleic acid has complex phase behavior with respect to the protonation state of the carboxylic head group, which depends on the pH of the solution. Oils form at low pHs, vesicles at intermediate pHs, and micelles at high pHs. We use constant pH molecular dynamics with the MARTINI coarse-grained model to investigate oleic acid aggregates at different pH conditions. We determine titration curves for the oleic acid monomers in different aggregates, and observe a shift in the microscopic pKa. In agreement with experimental results, th…

Quantitative separation of Trichoderma lipid classes on a bonded phase column.

1992

Bond Elut aminopropyl columns were used to purify the different lipid classes of Trichoderma harzianum and Trichoderma viride. This methodology permitted good separation of the fungal lipid classes in less time than traditional techniques. The incorporation of [1 (14)C]linoleic acid into neutral lipids, free fatty acids and phospholipids was quantified for both strains. The fatty acid profile of the different lipid classes of these fungal strains was determined as a function of culture time.

Digestion and absorption of polyunsaturated fatty acids

1991

Polyunsaturated fatty acids play an important part in the structure and function of cellular membranes and are precursors of lipid mediators which play a key role in cardiovascular and inflammatory diseases. Dietary sources of essential fatty acids are vegetable oils for either linoleic or alpha-linolenic acids, and sea fish oils for eicosapentaenoic and docosahexaenoic acids. Because of the specificity of the pancreatic lipid hydrolases, triglyceride fatty acid distribution is an essential parameter in the digestibility of fats. The efficiency of the intestinal uptake depends on the hydrolysis and especially on their micellarization. n-3 polyunsaturated fatty acid ethyl ester digestion is …

Unsaturated fatty acid bioavailability in growing rats fed low or adequate protein diets with sunflower or soybean oils

1993

Abstract The relationship of serum very low density lipoproteins (VLDL) to hepatic lipid composition was studied after 28 days of protein depletion to determine the interactions between dietary protein levels and the essential fatty acid (EFA) availability. This was examined in rats using a dietary combination of 20% or 2% casein with 5% vegetable oils, variable in their n-6:n-3 fatty acid ratios. Rats were divided into four groups, SFC (20% casein + 5% sunflower oil ); SFd (2% casein + 5% sunflower oil ); SC (20% casein + 5% soybean oil ); Sd (2% casein + 5% soybean oil ). Dietary protein depletion decreased phospholipid and protein concentrations in liver and VLDL, whereas triacylglycerol…

Effects of gamma-irradiation on the alpha-tocopherol and fatty acids content of raw unpeeled almond kernels (Prunus dulcis)

2014

Abstract The present study evaluated fatty acid composition and α-tocopherol content of almond as a function of irradiation dose in order to determine dose levels causing minimal undesirable changes to almonds. Raw unpeeled almonds variety Tuono ( Prunus dulcis (Mill.) D. A. Webb) were irradiated using 60 Co source at dose of 0.5, 1.5, 3, 6, 8 and 10 kGy. Both control and irradiated samples were kept frozen and immediately analyzed. The data obtained showed no change in fatty acid compositions up to a dose of 10 kGy; on the contrary, a general trend observed is that increasing the dose of irradiation resulted in the decrease of α-tocopherol content. The study has shown that irradiation is a…

On the problematic nature of vitamin E requirements: net vitamin E

1991

The requirement for vitamin E is closely related to the dietary intake of polyunsaturated fatty acids (PUFA). By the protective mechanism to prevent PUFA from being peroxidized, vitamin E is metabolically consumed. In addition, PUFA impair the intestinal absorption of vitamin E. Therefore PUFA generate an additional vitamin E requirement on the order of 0.6, 0.9, 1.2, 1.5, and 1.8 mg vitamin E (RRR-alpha-tocopherol-equivalents), respectively, for 1 g of dienoic, trienoic, tetraenoic, pentaenoic, and hexaenoic acid. For this reason, the gross vitamin E content of food containing PUFA does not allow an evaluation of this food as a source of vitamin E. A suitable measure is the net vitamin E c…

Vaccinium Genus Berry Waxes and Oils

2019

Vaccinium is a common and widespread genus of about 450 species of shrubs or dwarf shrubs in the heath family (Ericaceae). Most of Vaccinium species produce edible berries and many berries are widely cultivated at an industrial scale, for example, bilberries (Vaccinium myrtillus L.), highbush blueberries (Vaccinium corymbosum L.), lingonberries (Vaccinium vitis-idaea L.), and cranberries (Vaccinium oxycoccos L.). These berries are important articles in the markets of berries in Northern countries both raw, and processed. Vaccinium berries are at first valued considering high vitamin concentrations as well as high concentrations of phenolics. However, also oils and waxes (lipids) of Vacciniu…

Revisiting delta-6 desaturase regulation by C18 unsaturated fatty acids, depending on the nutritional status.

2009

Dietary polyunsaturated fatty acids (PUFA) play a key role in regulating delta-6 desaturase (D6D), the key enzyme for long-chain PUFA biosynthesis. Nevertheless, the extent of their effects on this enzyme remains controversial and difficult to assess. It has been generally admitted that C18 unsaturated fatty acids (UFAs) regulate negatively delta-6 desaturase (D6D). This inhibition has been evidenced in regard to a high glucose/fat free (HG/FF) diet used in reference. However, several nutritional investigations did not evidence any inhibition of desaturases when feeding fatty acids. Because the choice of the basal diet appeared to be of primary importance in such experiments, our goal was t…