Lipids animal

Steroids are plant and animal lipids with a characteristic tetracyclic carbon skeleton. Like the eicosanoids, steroids occur widely in body tissues and have a large variety of physiological activities. Steroids are closely related to terpenoids and arise biosynthetically from the triterpene lanosterol. Lanosterol, in turn, arises from cationic cyclization of the acyclic hydrocarbon squalene. 

Table 1.3 Fatty acid percentage composition of some fresh vegetable oils and of animal lipids... 

Lipids represent a remarkable class among the organic substances found in archaeological remains and works of art. They can derive from many sources, including vegetable oils, animal lipids, and waxes, and they have been used in many different ways in art and everyday activities. Lipid materials have been used extensively by ancient and modern populations as food, illuminants, waterproofing materials, binders, ingredients in medicines, cosmetics and balms. 

Plant lipids generally have an even number of carbon FAs, while animal lipids include odd-numbered carbon chain FAs, and, in some cases, branched chain FAs formed by bacterial activity in the digestive tract of ruminant mammals [5,41]. Branched FAs can also be formed in low amounts from other kind of lipids as a result of microbial activity after burial. 

Dietschy, J. M. and Turley, S. D. Thematic review series brain lipids. Cholesterol metabolism in the central nervous system during early development and in the mature animal. /. Lipid Res. 45 1375-1397,2004. 

Tetradecanoic Myristic C14 0 High in seed fat of Myristiceae, minor in most animal lipids... 

Tran. -isomers are much rarer than cis-isomers. Many different positional isomers of monoenoic acids may be present in a single, natural lipid and this is not a comprehensive list. Palmitoleic and oleic acids are quantitatively the commonest unsaturated fatty acids in most organisms. Odd-chain monoenoic acids are minor components of animal lipids but are more significant in some fish and bacterial lipids. 

The partition coefficient Kq of an organic compound in the 1-octanol/water system is used to assess the bioaccumulation potential and the distribution pattern of drugs and pollutants. The partition coefficient of imidazole and ILs strongly depends on the hydrogen bond formed by these molecules and is less than one due to the high solubility in water. The low value of the 1-octanol/water partition coefficient is required for new substances, solvents, insecticides to avoid bioaccumulation. Kqw is an extremely important quantity because it is the basis of correlations to calculate bioaccumulation, toxicity, and sorption to soils and sediments. Computing the activity of a chemical in human, fish, or animal lipid, which is where pollutants that are hydrophobic will appear, is a difficult task. Thus, it is simpler to measure the 1-octanol/water partition coefficient. This parameter is used as the primary parameter characterizing hydrophobisity. 

In the coevolutionary interactions of plants and animals, lipids play a major role. They function as ecomones (pheromones, allomones and kairomones) and have been classified by their function. Host plant resistance is partially dependent on these chemical constituents. Lipids may be subdivided into two types. Volatile lipids are generally involved in long distance interactions whereas non-volatile lipids are generally involved after the insect has contacted the host plant. Several examples of each are reviewed. Utilization of these compounds to promote increased host plant resistance could be accomplished by selection of plants rich in allomones, lacking kairomones for a particular pest or those with inducible systems of defense. Another approach is to isolate the defensive compounds of one plant and apply them to crop plants. Trap crops could also be used to lure insects away from other crops. 

If analysis is to be attempted with a detection system of only moderate selectivity, a substantial cleanup procedure may be required in order to enhance the concentration of the extracted trace residue while decreasing die concentration of possible interfering substances in the sample matrix. This is die case with most of the relatively nonspecific physicochemical detection systems used in residue analysis. Occasionally a sample may be suitable for direct physicochemical analysis after an extraction and concentration step. However, the majority of edible animal products need extensive cleanup to separate the compounds of interest from animal lipids and other natural organic substances prior to detection. For such detection systems, there has been a general rule dictating diat the cleaner sample, the better the result obtained. 

Marine lipids with their diversity of unsaturated and branched chain acid moieties are a difficult class of materials to analyze. Ruminants (sheep, goats, cows, etc.) have a bacterial "factory" in the rumen which is able to produce branched-chain partially-hydrogenated lipids from ingested plant lipids. These lipids are incorporated into the milk and meat of the animals and eventually into animals which feed upon the ruminants. As a rule animal lipids are highly complex in comparison to plant materials. Although the branched chain materials are usually present in low concentration when compared to the common fatty acid moieties, complete description of these fats requires more sophisticated GC and thus long open tubular columns in tandem with mass spectrometry and computer analysis of the data has become an important approach. Even with a 100-m column, subcutaneous lipids of barley-fed lambs were so complex that prior fractionation with urea adducts was necessary (17). 

First reported in recent marine sediments in 1967 275) have since been found in several marine basins 140, 141) Cooper and Blumer 140) suggested that the isoprenoid acids may provide markers for the contribution of animals lipids to the organic matter of recent sediments... 

Another enzyme, in addition to the isomerase, is required for the oxidation of polyunsaturated fatty acids which have a double bond at an even-numbered carbon atom. In this case the 2,4-dienoyl intermediate resulting from the action of acyl CoA dehydrogenase is acted on by 2,4-dienoyl CoA reductase to form c/s-A3-enoyl CoA (Fig. 4). This is then converted by the isomerase into the trans form which continues down the pathway. These reactions are important since over half the fatty acids of plant and animal lipids are unsaturated (and often polyunsaturated). 

Each of the studies mentioned so far is fundamentally correlative, with lipid-phase behavior and water-loss rates being measured with different animals. Lipid composition and physical properties can vary substantially within species, so a close correlation between these parameters is not necessarily expected. One possible explanation is a file drawer problem of the type alluded to by Lighton (1998) results that conflict with the... 

Brockerhoff, H., Hoyle, R.R., Hwang, P.C. and Litchfield, C. (1968) Positional distribution of fatty acids in depot triglycerides of aquatic animals. Lipids, 3, 24. 

Because octanol was selected to simulate animal lipids, A b is related to Kow the empirical relationship is... 

Numerous studies document PCBs in food suppfies as seen from the perspective of human exposure (Davies, 1988 Schecter and Piskac, 2001). Due to their hydrophobicity, PCB concentrations track closely concentrations of fat and lipids, resulting in foods rich in animal lipids, such as fatty fish, cheese and meats, having the highest concentrations, as seen in Figure 8.4 (e.g. Watanabe et al, 1979 Wilson et al, 2003 Schaeffer et al, 2006 Koizumi et al, 2005). 

The vitamin also activates serine palmitoyltransferase, the first enzyme of phosphosphingolipid synthesis, and in bacteria it can, together with inorganic phosphate, replace part of the ATP requirement of galactocerebroside sulfo-transferase (Tsaioun, 1999). In animals, lipid sulfatides are decreased in vitamin K deficiency and increased with higher intakes (Sundaram et al., 1996). 

Lipids are biological materials that are insoluble in water but soluble in nonpolar organic solvents. Here the term will be used interchangeably with acylglycerol, the primary component of animal lipids. These are classihed as either fats or oils. The former are predominantly solid at room temperature (24°C), and the latter are liquid. The depot lipids of animals are generally fats. The major animal fats (also termed meat fats) of contemporary commerce are produced from pigs Sus scrofa), in which case they are termed lard and rendered pork fat, from the fat of cattle Bos taurus) or sheep Ovis aries) and termed tallow, or from poultry (primarily chickens. Callus gallus) and termed poultry fat. Tallow... 

Examination of Table 1 shows that the prevalent fatty acids in animal depot lipids are either 16 or 18 carbons in length and are either fuUy saturated or contain one or two double bonds. Animal lipids generally contain a higher proportion of samrated fatty acids than do the lipids of temperate zone plants. 

Systematic name is based on replacing the final letter e of the parent hydrocarbon with oic. " "Most abundant fatty acids present in animal lipids. 

Palmitoleic and oleic acids, the two most abundant monounsaturated fatty acids of animal lipids, can be... 

This series is based on the number of carbon atoms present between the terminal methyl group and the nearest double bond (0-3 and (0-6 are essential fatty acids. Most abundant unsaturated fatty acids in animal lipids. 

The most common fatty acids are chains of 12 to 26 carbon atoms with a carboxylic acid group at one end. They usually have an even number of carbon atoms because they are made from smaller molecules with two carbons. Saturated fatty acids, like saturated hydrocarbons, have only single bonds connecting the carbon atoms. Monounsaturated fatty acids have one double bond between two of the carbon atoms, as you can see in Figure 19.11. Fatty acids that are polyunsaturated have two or more double bonds. In general, animal lipids are more saturated than are plant lipids. 

Describe the functions of lipids and their solubility properties. Are animal lipids or plant lipids generally more saturated ... 

Recent studies by Ross et.al. have demonstrated that resorcinolic lipids (5-alkylresorcinols) present in high fibre whole grain cereal diet can be used as biomarkers, i.e. compounds that can be used for the epidemiological studies of the effects of dietary intake in human health [412-415]. These phenolic compounds are absorbed from the ileum by animals and humans and may be determined quantitatively in the serum [416] and their metabolites also in human urine [412], Further data confirm that cereal grain 5-alkylreesorcinols modify animal lipid metabolism in vivo and in vitro [413,417] which make them very interesting in relation to the risks of diabetes, obesity, heart diseases and some cancers. 

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