Lipid content

Bioconcentration, Bio accumulation and Biomagnification. These aspects are determined by the physicochemical properties of a chemical, an organism s ability to excrete the chemical, the organism s lipid content and its trophic level. Bioconcentration relates to the difference between the environmental concentration and that of the body tissues. A high bioconcentration factor (BCF) predisposes to bioaccnmulation. The upper limit of bioaccnmulation is determined by lipid levels in the organism s tissues. Whether the resultant body burden causes biomagnification in the food chain depends upon the metabolic capabilities of the exposed organism. 

FATP5 KO mice have been characterized in two studies focusing on the role of FATP5 in hepatic lipid and bile metabolism. LCFA uptake in primary hepato-cytes isolated from FATP5 KO mice was reduced by 50% and hepatic lipid content in the KO mice was significantly reduced despite an increased fatty acid de novo biosynthesis. Detailed analysis of the hepatic lipidome of FATP5 KO mice revealed significant... 

Decreased lipid content of the skin Increased body fat decreased body water... 

This outcome was consistent with a hypothesis that structural deterioration could have been a byproduct of microorganism activity. The higher lipid content in the poorly preserved tissue suggests that those lipids are primarily extrinsic, that is, that they were produced by bacteria and/or fungi. As the food source for such microorganisms, the protein within the bone may have been substantially altered in concert with the microstructure deterioration. The quantification of the changes to the organic fraction became our next focus of research. 

The lipid content of the membranes can be varied, allowing systematic examination of the effects of varying lipid composition on certain functions. For instance, vesicles can be made that are composed solely of phosphatidylchohne or, alternatively, of known mixtures of different phospholipids, glycohpids, and cholesterol. The fatty acid moieties of the lipids used can also be varied by employing synthetic lipids of known... 

Crisby M, Nordin-Fredriksson G, Shah PK, Yano J, Zhu J, Nilsson J. Pravastatin treatment increases collagen content and decreases lipid content, inflammation, metalloproteinases, and cell death in human carotid plaques implications for plaque stabilization. Circulation 2001 103(7) 926-933. 

The food matrix including its fiber and lipid content and concentrations of other carotenoids in the diet may influence the extent of absorption of carotenoid compounds. The relative absorption of lutein from a mixed vegetable diet was lower than from a diet containing pure lutein. A mixed preparation of lutein and zeaxanthin did not influence the absorption of P-carotene. 

Ratnayake, W. M. N., Hollywood, R., O Grady, E., and Stavric, B., Lipid content and composition of coffee brews prepared by different methods, Food Chem. Toxicol., 31(4), 263, 1993. (CA119 27040a)... 

The negative-charge lipid content in the egg lecithins is not as high as that found in BBM and especially BBB lipids (Table 7.1). Furthermore, the negative-charge content in the egg lecithin is about one-fourth that in the soy lecithin. This is clearly evident in the membrane retention parameters for the bases at the 10% lecithin levels (models 12.0 or 14.0 in Table 7.8 vs. model 16.0 in Table 7.12), as they are 20-30% lower for the lipophilic bases in egg, compared to soy. 

As has been pointed out earlier in this chapter, the dietary consumption and historical medicinal use of carotenoids has been well documented. In the modern age, in addition to crocin, 3.7, and norbixin, 3.8, several carotenoids have become extremely important commercially. These include, in particular, astaxanthin, 3.6 (fish, swine, and poultry feed, and recently human nutritional supplements) lutein, 3.4, and zeaxanthin, 3.3 (animal feed and poultry egg production, human nutritional supplements) and lycopene, 3.2 (human nutritional supplements). The inherent lipophilicity of these compounds has limited their potential applications as hydrophilic additives without significant formulation efforts in the diet, the lipid content of the meal increases the absorption of these nutrients, however, parenteral administration to potentially effective therapeutic levels requires separate formulation that is sometimes ineffective or toxic (Lockwood et al. 2003). 

Most commonly, the lipid metabolism pathology is manifest as hyperlipemia (elevated concentration of lipids in blood) and tissue lipidoses (excessive lipid de-position in tissues). Normally, the lipid contents in the blood plasma are total lipids, 4-8 g/litre triglycerides, 0.5-2.1 mmol/litre total phospholipids, 2.0-3.5 mmol/litre total cholesterol, 4.0-8.0 mmol/litre (esterified cholesterol accounts for 2/3 of total cholesterol). 

Proulx [30] summarized the published lipid compositions of BBM isolated from epithelial cells from pig, rabbit, mouse and rat small intestines. Table 3.1 shows the lipid make-up for the rat, averaged from five reported studies [30], On a molar basis, cholesterol accounts for about 50% of the total lipid content (37% on a weight basis). Thus, the cholesterol content in BBM is higher than that found in kidney epithelial (MDCK) and brain endothelial cells (Table 3.1). Slightly different BBM lipid distribution was reported by Alcorn et al. [31] here, the outer (luminal) leaflet of the BBM was seen to be rich in sphingomyelin content, while the inner leaflet (cytosol) was rich in PE and PC. Apical (brush border) and basolateral lipids are different in epithelia. The basolateral membrane content (not reported by... 

Essen-Gustafson B, Karlson A, Lundstrom K and Entfallt A-C (1994), Intramuscular fat and muscle fibre lipid contents in halothane-gene-free pigs fed high or low protein diets and its relation to meat quality , Meat Sci, 38, 269-211. 

This proxy approach has recently been used to provide the earliest evidence for prehistoric milk use (Evershed et cd. 2008). A study of the lipid content of >2200 pottery vessels from sites in the Near East and the Balkans dating from the fifth to seventh millennia was carried out. It was shown that milk was in use by the seventh millennium... 

Abstract To understand how membrane-active peptides (MAPs) function in vivo, it is essential to obtain structural information about them in their membrane-bound state. Most biophysical approaches rely on the use of bilayers prepared from synthetic phospholipids, i.e. artificial model membranes. A particularly successful structural method is solid-state NMR, which makes use of macroscopically oriented lipid bilayers to study selectively isotope-labelled peptides. Native biomembranes, however, have a far more complex lipid composition and a significant non-lipidic content (protein and carbohydrate). Model membranes, therefore, are not really adequate to address questions concerning for example the selectivity of these membranolytic peptides against prokaryotic vs eukaryotic cells, their varying activities against different bacterial strains, or other related biological issues. 

Extraction of an analyte from a complex matrix, such as foods, is often dependent on the moisture and lipid content of the matrix. Hence, sample pretreatment... 

The Definition of Lecithin. Lecithin for use in food is defined as A mixture of polar and neutral lipids with a polar lipid content of at least 60%. NB this is different from the scientific usage where lecithin is used as a trivial name for phosphatidylcholine. 

Although apoE HDL particles are formed by astrocytes in vitro, the brain contents of apoE knockout (-/-) were not found to differ in lipid content in comparison to those obtained from normal animals [14]. A probable explanation is that newly synthesized cholesterol can be transported from astrocyte ER to plasma membrane via an alternative route that employs caveolae to form apoAl-HDL [15]. 

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