triolein and stearic-acid

In the present study, we investigated the effect of long-acyl chain SFA, namely palmitic acid (16:0) and stearic acid (18:0), at sn-1, 3 positions of TAG on obesity. Throughout the 15 weeks of the experimental period, C57BL/6 mice were fed diets fortified with cocoa butter, sal stearin (SAL), palm mid fraction (PMF) and high-oleic sunflower oil (HOS). The sn-1, 3 positions were varied by 16:0, 18:0 and 18:1, whilst the sn-2 position was preserved with 18:1. The HOS-enriched diet was found to lead to the highest fat deposition. This was in accordance with our previous postulation. Upon normalisation of total fat deposited with food intake to obtain the fat:feed ratio, interestingly, mice fed the SAL-enriched diet exhibited significantly lower visceral fat/feed and total fat/feed compared with those fed the PMF-enriched diet, despite their similarity in SFA-unsaturated fatty acid-SFA profile. That long-chain SFA at sn-1, 3 positions concomitantly with an unsaturated FA at the sn-2 position exert an obesity-reducing effect was further validated. The present study is the first of its kind to demonstrate that SFA of different chain lengths at sn-1, 3 positions exert profound effects on fat accretion.

Topics: Adiposity; Animals; Diet, High-Fat; Dietary Fats; Feces; Intestinal Absorption; Intra-Abdominal Fat; Male; Mice; Mice, Inbred C57BL; Obesity; Oleic Acid; Palm Oil; Palmitic Acid; Plant Oils; Random Allocation; Stearic Acids; Subcutaneous Fat; Sunflower Oil; Triglycerides; Triolein; Weight Gain

X-linked adrenoleukodystrophy (X-ALD) is a peroxisomal disorder caused by impaired degradation of very long-chain fatty acids (VLCFAs) due to mutations in the ABCD1 gene responsible for VLCFA transport into peroxisomes. Lorenzo's oil, a 4:1 mixture of glyceryl trioleate and glyceryl trierucate, has been used to reduce the saturated VLCFA level in the plasma of X-ALD patients; however, the mechanism by which this occurs remains elusive. We report the biochemical characterization of Lorenzo's oil activity toward elongation of very long-chain fatty acid (ELOVL) 1, the primary enzyme responsible for the synthesis of saturated and monounsaturated VLCFAs. Oleic and erucic acids inhibited ELOVL1, and, moreover, their 4:1 mixture (the FA composition of Lorenzo's oil) exhibited the most potent inhibitory activity. The kinetics analysis revealed that this was a mixed (not a competitive) inhibition. At the cellular level, treatment with the 4:1 mixture reduced the level of SM with a saturated VLCFA accompanied by an increased level of SM with a monounsaturated VLCFA, probably due to the incorporation of erucic acid into the FA elongation cycle. These results suggest that inhibition of ELOVL1 may be an underlying mechanism by which Lorenzo's oil exerts its action.

Topics: Acetyltransferases; Dose-Response Relationship, Drug; Drug Combinations; Erucic Acids; Fatty Acid Elongases; Fatty Acids; Gene Expression Regulation, Enzymologic; HEK293 Cells; HeLa Cells; Humans; Immunoblotting; Kinetics; Oleic Acid; Palmitic Acid; Reverse Transcriptase Polymerase Chain Reaction; Sphingomyelins; Stearic Acids; Triolein

Studies with teleost larvae have reported poor performance associated with quantitative lipid imbalances in the diet. The present study examined the effect of dietary protein:neutral lipid ratio on fatty acid (FA) absorption efficiency and metabolism in larval Senegalese sole. In addition, the effect of lipid class (triolein (TRI) and l-3-phosphatidylcholine-1,2-di-oleoyl (PC)), carbon number and degree of saturation of the labelled NEFA, stearic acid (SA), oleic acid (OA) and DHA) was tested. FA absorption was determined by tube feeding [1-14C]-labelled lipids and NEFA after a single meal of either non-enriched Artemia (NEA) or Artemia enriched on a soyabean oil emulsion (EA), or after feeding these diets over an extended period of time (18 d). The tested dietary protein:lipid ratios had no short-term influence but long-term feeding of a diet higher in neutral lipid (EA) increased lipid accumulation within the gut epithelium and resulted in lower FA absorption (higher label evacuation and lower retention of dietary FA), which may partially explain the trend for lower growth observed with this diet. The lipids and NEFA, showed different digestive and metabolic properties, independent of feeding regime. FA absorption increased with unsaturation, being lowest for SA, followed by OA, and highest for DHA. In addition, sole larvae had a lower capacity to digest and absorb FA esterified to TRI, compared with PC, with the order of decreasing absorption being NEFA>PC>>TRI. Moreover, larvae appeared to discriminate between the source of OA, as this FA in the free form or esterified to PC was catabolised less than TRI.

Topics: Absorption; Animals; Artemia; Dietary Proteins; Docosahexaenoic Acids; Fatty Acids; Fatty Acids, Nonesterified; Flatfishes; Lipid Metabolism; Lipid Peroxides; Liver; Oleic Acid; Phosphatidylcholines; Stearic Acids; Triolein

Heating amino acids with dietary oils or animal fats at elevated temperatures produced various amounts of acrylamide. The amount of acrylamide formation corresponded to the degree of unsaturation of the oils and animal fats. The decreasing order of acrylamide formation from dietary oils or animal fats with asparagine was sardine oil (642 microg/g asparagine) > cod liver oil (435.4 microg/g) > soybean oil (135.8 microg/g) > corn oil (80.7 microg/g) > olive oil (73.6 microg/g) > canola oil (70.7 microg/g) > corn oil (62.1 microg/g) > beef fat (59.3 microg/g) > lard (36.0 microg/g). Three-carbon unit compounds such as acrylic acid and acrolein, which are formed from lipids by oxidation also produced acrylamide by heat treatment with amino acids, in particular with asparagine. The results of the present study suggest that acrylamide forms in asparagine-rich foods during deep fat frying in the absence reducing sugars.

Topics: Acrolein; Acrylamide; Acrylates; Amino Acids; Asparagine; Carbohydrates; Chromatography, Gas; Chromatography, Liquid; Cod Liver Oil; Corn Oil; Dietary Fats; Dietary Fats, Unsaturated; Dose-Response Relationship, Drug; Fatty Acids, Monounsaturated; Hot Temperature; Lipids; Models, Chemical; Oils; Olive Oil; Oxygen; Plant Oils; Rapeseed Oil; Soybean Oil; Stearic Acids; Temperature; Triolein

A wide range of lipids are present on the skin surface of human beings and bacterial lipases are known to modify them. The microflora of the underarm (axilla) is often dominated by aerobic coryneforms and whilst many require lipids for growth, they appear not to be utilized as carbon sources. The aim of this study was to investigate the adherence aerobic coryneforms to lipids present on the skin surface of the human axilla to determine whether they contribute to colonization of the skin.. Aerobic coryneforms were grown in a defined synthetic medium in the presence of (14)C-glucose to produce radio-labelled cells. Adherence to lipids was tested using a thin layer chromatography plate-based assay.. The mechanism of bacterial adhesion to skin lipids is unknown. The results of this study show that a significant proportion of cutaneous aerobic coryneform isolates from the axilla interact with skin lipids resulting in increased adherence, which may contribute to skin colonization.

Topics: Actinomycetales; Axilla; Bacteria, Aerobic; Bacterial Adhesion; Carbon Isotopes; Cholesterol; Cholesterol Esters; Diglycerides; Glycerides; Linoleic Acid; Lipid Metabolism; Oleic Acid; Skin; Squalene; Stearic Acids; Triglycerides; Triolein

The Arabian Gulf is one of the most extensively oil-polluted areas of the world. The major objectives of this work were to study whether hydrocarbon-utilizing microorganisms indigenous to that area would readily accumulate added lipids, and whether this might affect their hydrocarbon consumption potential. Two prokaryotes, Arthrobacter nicotianae KCC B35 and the unidentified organisms KCC B6, as well as one eukaryote, Candida parapsilosis KCC Y1, were selected for this study. Biomass samples of the test organisms were incubated in an inorganic medium containing various concentrations of cholesterol, stearic acid, triolein or egg-phospholipids. The results revealed that all lipid classes were readily accumulated by the three test organisms. In addition, biomass samples were incubated for 6 h in an inorganic medium containing mixtures of individual lipid classes and either n-octadecane or n-docosane. The cells were removed and the residual alkanes in the medium were quantitatively recovered and analyzed by GLC. The results showed that out of the tested lipid classes only stearic acid exhibited a common stimulatory effect on the consumption of both n-alkanes by all test organisms. Other lipid classes were either inhibitory or had less pronounced effects than stearic acid.

Topics: Alkanes; Arthrobacter; Biodegradation, Environmental; Biomass; Candida; Cholesterol; Culture Media; Fuel Oils; Phospholipids; Seawater; Stearic Acids; Triolein

Previous work showed that the clearance from plasma of chylomicron-like emulsions injected intravenously was affected by the acyl chains of the constituent triacylglycerols. Compared with emulsions containing triolein (OOO) as the only triacylglycerol, clearances were decreased by a single saturated chain in emulsions containing 1,3-dioleoyl-2-stearoyl-sn-glycerol (OSO), 1,2-dioleoyl-3-stearoyl-sn-glycerol (OOS) or 1-stearoyl-2,3-dioleoyl-sn-glycerol (SOO). The differences in clearance may reflect physical differences at the oil-water interface related to chain interactions of the triacylglycerol structures with other lipid components. In the present work lipid monomolecular films at the air-water interface were used to establish the capacity of OOO to interact with the pure synthetic triacylglycerols OOS and SOO, and the capacity of OOS and SOO to co-exist in monolayers of lecithin and of cholesterol was compared with OOO. Substituting one oleoyl chain by a stearoyl chain induced a 20% condensation in monomolecular films of the pure triacylglycerols. Mixtures of OOO with either pure egg yolk phosphatidylcholine or cholesterol also showed substantial condensing effects. In contrast substituting one oleoyl chain by a stearoyl chain substantially lessened the condensing effects. At surface pressures above the collapse pressure of the pure triacylglycerols, substantially more OOO than OOS or SOO was retained in mixed monolayers with phosphatidylcholine. These differences could underlie the effects on metabolism of saturated chains in emulsion triacylglycerols.

Topics: Chemical Phenomena; Chemistry, Physical; Cholesterol; Emulsions; Oleic Acid; Oleic Acids; Phosphatidylcholines; Stearic Acids; Triglycerides; Triolein

Topics: Angina Pectoris; Blood Coagulation; Blood Coagulation Tests; Cholesterol; Diabetes Mellitus; Dietary Fats; Geriatrics; Humans; Linoleic Acid; Lipids; Myocardial Infarction; Palmitic Acid; Pharmacology; Stearic Acids; Thromboplastin; Triolein

Topics: Animals; Antibody Formation; Antigens; Chromium Isotopes; Immunity; Lipids; Mice; Mononuclear Phagocyte System; Phagocytosis; Rats; Research; Spleen; Stearic Acids; Triolein

Topics: Bile Acids and Salts; Biochemical Phenomena; Biochemistry; Butyrates; Caproates; Caprylates; Cholesterol; Esterases; In Vitro Techniques; Linoleic Acid; Lipase; Magnesium; Oleic Acid; Oleic Acids; Pancreatic Juice; Phospholipids; Propionates; Research; Salts; Serum Albumin; Stearic Acids; Sterol Esterase; Triolein

Topics: Acetates; Butyrates; Cholesterol; Chromatography; Fatty Acids; Glycerides; Lipids; Oils; Palmitic Acid; Polymers; Rats; Research; Stearic Acids; Triolein