Search results for "Lipid composition"
showing 9 items of 9 documents
A Perspective : Active Role of Lipids in Neurotransmitter Dynamics
2019
AbstractSynaptic neurotransmission is generally considered as a function of membrane-embedded receptors and ion channels in response to the neurotransmitter (NT) release and binding. This perspective aims to widen the protein-centric view by including another vital component—the synaptic membrane—in the discussion. A vast set of atomistic molecular dynamics simulations and biophysical experiments indicate that NTs are divided into membrane-binding and membrane-nonbinding categories. The binary choice takes place at the water-membrane interface and follows closely the positioning of the receptors’ binding sites in relation to the membrane. Accordingly, when a lipophilic NT is on route to a m…
Partial substitution of fish meal with vegetable protein sources in a diet for sea bass: effects on lipogenesis
2005
Three isoproteic (49.4%) and isolipidic (17.0%) diets were prepared: A control diet FM, in which protein was derived from fish meal and two experimental diets in which 70% of the fish meal protein was substituted with wheat gluten meal (WGM) or wheat gluten meal plus soybean meal (WGMsb), respectively. The essential limiting amino acids were added to satisfy the requirements of the species (Tibaldi et al., 1996). Three hundred and fifteen sea bass (initial weight = 23.9±0. 1g )were randomly divided into nine homogenous groups. The animals were reared in a closed recirculation system at 23.9 ◦ C and were fed ad libitum twice a day for 96 days. The fish were weighed at the beginning and the e…
Pharmacokinetics of oligodeoxynucleotides encapsulated in liposomes: effect of lipid composition and preparation method
2000
1. The effect of the method employed to prepare liposomes and their lipid composition were evaluated in terms of the encapsulation efficiency and pharmacokinetic features of two oligodeoxynucleotides of a 21 mer: the normal (N-Odn) and the phosphorothioate (S-Odn) oligodeoxynucleotide. 2. Liposomes were prepared by the classical method of multilamellar vesicles (MV) and by the dehydration-rehydration method (DR). Two lipid mixtures were used to prepare liposomes--the predominant lipid being phosphatidylcholine (PC) and sphingomyelin (SM) respectively. 3. The DR method for liposome preparation provided the highest encapsulation efficiency, regardless of liposome lipid composition and the typ…
Quality of dietary supplements in ophthalmology
2006
International audience; Purpose: A rising number of dietary supplements are available to prevent age–related ocular pathologies such as AMD or dry eye syndrome. The purpose of this work was to evaluate the quality of dietary supplements containing omega–3 polyunsaturated fatty acids in terms of lipid, vitamin E and heavy metals composition. Dietary supplements designed for improving mental well–being were included in this study since they should share some similarities.Methods: Twenty dietary complements were analyzed (6 for dry eye prevention, 4 for AMD prevention and 10 for improving mental well–being). Lipids and lipophilic vitamins were extracted. The distribution of the lipid classes w…
The salt and lipid composition of model cheeses modifies in-mouth flavour release and perception related to the free sodium ion content.
2014
Reducing salt and lipid levels in foodstuffs without any effect on acceptability is a major challenge, particularly because of their interactions with other ingredients. This study used a multimodal approach to understand the effects of changes to the composition of model cheeses (20/28, 24/24, 28/20 lipid/protein ratios, 0% and 1% added NaCl) on sodium ion mobility ((23)Na NMR), in-mouth sodium release and flavour perception. An increase in the salt content decreased cheese firmness and perceived hardness, and increased sodium ion mobility, in vivo sodium release and both saltiness and aroma perception. With the same amount of salt, a lower lipid/protein ratio increased the firmness of the…
(19)F NMR screening of unrelated antimicrobial peptides shows that membrane interactions are largely governed by lipids.
2014
AbstractMany amphiphilic antimicrobial peptides permeabilize bacterial membranes via successive steps of binding, re-alignment and/or oligomerization. Here, we have systematically compared the lipid interactions of two structurally unrelated peptides: the cyclic β-pleated gramicidin S (GS), and the α-helical PGLa. 19F NMR was used to screen their molecular alignment in various model membranes over a wide range of temperatures. Both peptides were found to respond to the phase state and composition of these different samples in a similar way. In phosphatidylcholines, both peptides first bind to the bilayer surface. Above a certain threshold concentration they can re-align and immerse more dee…
Analysis of lipids in pelagic fish of Sicilian Channel and use of fatty acids as bacterial contamination markers
Lipids provide the expendable form of energy in marine ecosystem, and have an important role for the reproductive biology of fish. Also, lipids are important nutrients, versatile markers for marine trophic studies, bacteria markers etc. Among the lipids, several essential fatty acids are determinants for ecosystem health as well as for their known nutritional properties and prevention capacity of chronic diseases. Furan fatty acids (F - acids) are other important lipid bioactive compounds; for these is hypothesized a crucial nutritional role that is synergistic to polyunsaturated fatty acids omega 3 (PUFA ω 3), also if their mechanism is not yet clear. Source of essential fatty acid is the …
Lipid and fatty acid variations inCiona intestinalis ovary after tri-n-butyltin(IV)chloride exposure
2005
Reduction of total lipids (TL) content and significant variations of triglyceride (TG) and phospholipid (PL) fractions were observed as a consequence of exposure of Ciona intestinalis ovaries to tributyltin chloride (TBTCL) solutions. In particular, an evident TG decrease and a PL increase were observed, which probably provoked an increment in membrane fluidity, because of the high concentration of long chain fatty acids and, as a consequence, PL. This could be a cell adaptive standing mechanism towards the pollutants, as observed in Saccharomyces cerevisiae. Also the increase in the content of the polyunsaturated fatty acids (PUFA), important in the synthesis of compounds such as prostagla…