Lipids total fatty acids

The Main Fatty Acids of Cereal Lipids (% total fatty acids)... 

Previously glycerides were usually calculated from values for total lipids, lipid phosphorus, free and esterified cholesterol. The difference between total lipids and the sum of phospholipids, free cholesterol and cholesterol esters was regarded as representing neutral lipids. For satisfactory results, non-lipid material has to be removed carefully from the lipid extracts. Since substances such as hydrocarbons, free fatty acids, fat-soluble vitamins etc. are also contained in the total lipids, they contribute to the calculated neutral fat values. Instead of total lipids, total fatty acids and total esterified fatty acids have been used. 

Lipid peroxidation is a radical-mediated chain reaction resulting in the degradation of polyunsaturated fatty acids (PUFAs) that contain more than two covalent carbon-carbon double bonds (reviewed by Esterbauer et al., 1992). One of the major carriers of plasma lipids is LDL, a spherical molecule with a molecular weight of 2.5x10 . A single LDL particle contains 1300 PUFA molecules (2700 total fatty-acid molecules) and is... 

Lipid C. pyrenoidosa % of total fatty acids C. vulagaris M. aeruginosa... 

Regarding the interference of lipids and fatty acids in preparation of LPC, Nagy et al. (15) made an extensive study of this problem and determined, as indicated in Table VII, that the lipid content and total lipid distribution in some green protein fractions is indeed significant and can present a problem with protein extractability and purification. They indicated however, most of the lipid appeared to come from extraction of cell walls and ruptured cellular contents during the maceration process. 

The effects of storage on lipids depend on potato variety (Mondy et al., 1963). Tuber storage at 4°C resulted in an initial small increase in total fatty acid content (Dobson et al., 2004). Prolonged storage resulted in a fall to the initial values detected close to harvest. The content... 

Since about 50% of C16 0 and 100% of C18 0, C18 , and C18.2 are derived from blood lipids, about 50% of the total fatty acids in ruminant milk fat originate from the blood via diet or other organs. 

Total fatty acids were liberated by subjecting Salmonella minnesota Re lipopolysaccharide (or free lipid A) to acidic (4 N HC1, 5 h, 100°C) followed by alkaline (1 N NaOH, 1 h, 100°C) hydrolysis. After extraction (chloroform), the free fatty acids were converted into their methyl esters (diazomethane) and analysed by combined gas-liquid chromatography/mass spectrometry. Alternatively, the fatty acids of lipid A are transesterified by treatment of lipopolysaccharide with methanolic HC1 (2 N HC1 in water-free CHaOH, 18 h, 85°C). By these procedures the following fatty acids were identified (in approximate amounts relative to 2 moles glucosamine) dodecanoic (12 0, 1.1 mole), tetradecanoic (14 0, 0.8 mole), hexadecanoic (16 0, 0.9 mole), 2-hydroxytetradecanoic (2-OH-l4 0, 0.1 mole), and 3-hydroxytetradecanoic acid (3-OH-14 0, 4 moles). In total, therefore, approximately 7 moles of fatty acids are present per mole of lipid A backbone. The stereochemistry of the hydroxylated fatty acids was determined by gas-liquid chromatography of their diastereomeric methoxyacyl-L-phenylethylamide derivatives (24). It was found that 2-hydroxyte-tradecanoic acid possesses the-Ts), and the predominating 3-hydroxytetradecanoic acid the (R) configuration. 

Results of chemical analysis showed that the glucosamine and total fatty acid contents of the KDO depleted, toxic lipid A and the nontoxic lipid A were essentially the same but that the nontoxic lipid A was significantly lower in the phosphorus content (Table V). The molar ratio of glucosamine phosphorus fatty acids was 2 2 4 for the toxic lipid A and 2 1 4 for the nontoxic lipid A. The relative molar distribution of normal fatty acids (lauric, myristic, and palmitic acids) and the 3-hydroxymyristic acid did not indicate a correlation between the content of these components and toxicity. The nontoxic lipid A possessed as high a tumor regression activity when combined with CWS as did the purified... 

Triglcerides Polar Lipids Beef Pork Beef Pork Fatty Acids % of Total Fatty Acid Content... 

The fatty acids of bovine milk fat arise from two sources synthesis de novo in the mammary glands and the plasma lipids originating from the feed. The fatty acids from these two sources differ in their structure. The fatty acids that are synthesised de novo are short-chain and medium-chain length acids, from 4 0 to 14 0 and also some 16 0, while the Cis fatty acids and some 16 0 arise from the plasma lipids. De novo fatty acid synthesis accounts for approximately 45% (w/w) of the total fatty acids in milk fat, while lipids of dietary origin account for the rest (Moore and Christie, 1979). 

Straight- or normal-chain (even-numbered) monoenoic fatty acids (with one double bond) amount to a significant proportion of the total fatty acids in most natural lipids. The double bond is usually of the cis- or Z-configuration, but some fatty acids with trans- or -double bonds are found. For example, a major fatty acid esterified to phosphatidylglycerol in the photosynthetic membranes of higher plants and algae is trans-3-hexadecenoic acid. Often the cis bond is present at the A9 position. 

Several studies have confirmed that the seed oil from the North American variety of cranberry contains significant levels of a-linolenic acid. In a U.S. patent, Heeg et al. (4) reported the a-linolenic acid content of cranberry seed oil to be between 30% and 35% of total fatty acids. In 2003, Parker et al. (5) found 22.3% a-linolenic acid in the cold-pressed cranberry seed oil, and in 2004, Parry et al. (3) determined the oil to contain 32.0% a-linolenic acid from two different lots of the seed oil. The ratios of n-6 to n-3 fatty acids in all were low from 1.2 1 to 2 1. Also, all of the studies documented similar ratios among the rest of the common fatty acids found in cranberry seed oil, including, in order of higher amount present linoleic, oleic, palmitic, stearic, and eicosadienoic (20 2) acids (Table 1). In addition to a-linolenic acid, cranberry seed oil is rich in natural antioxidants (8). These antioxidants may directly react with free radicals and prevent lipid oxidation in human low-density lipoprotein. 

Lipase-catalyzed hydrolysis of the vitamin esters in food samples in SCCO2 has been investigated as a pretreatment step in the analytical determination of vitamins in food samples (216, 217). Lipase-catalyzed transesterification of oils with methanol have been used for the determination of total fat content in lipid-containing samples such as oilseeds and meat samples (218, 219) and for the determination of fatty or resin acid content of tall oil products (220). Esterification of fatty acids with methanol in SCCO2 has been reported for total fatty acid analysis of soapstock (221). 

The leaves of higher plants contain upto 7% of their dry weight as fats some of which are present as surface lipids, the others as components of leaf cells, especially in the chloroplast membrane. The fatty acid composition of plant membrane lipids is very simple. Six fatty acids- palmitic, palmitoleic, stearic, oleic, linoleic and y-linolenic generally account for over 90% of the total fatty acids. 

Effect of Culture Aoe. Sample age of Skeletonema affected the fatty acid composition of batch 2 compared to batches 1, 3, and 4 (Table I). At harvest time batches 1, 3, and 4 were two weeks old whereas batch 2 was three weeks old. The total fatty acid content was 35.2, 48.7, 24.2 and 60.1 mg fatty acid/g of dried algae for batches one through four, respectively. Figure 14 indicates the difference in the fatty acid profiles between two and three week old cultures. A sharp increase was observed in the production of C14 0 (260%) and C16 l (230%) for the three week old culture compared to the two week old culture. The relative proportion of C20 5w3 for the three week old culture was smaller compared to the two week culture (0.16 versus 0.07). Ackman et al.(6) reported a decrease in the degree of unsaturation in the lipids of Skeletonema costatum with maturity. Figure 14 indicates that the overall level of lipids were 75% higher in the three week old cultures compared to the two week old cultures. It is also evident from the same figure that the proportion of polyunsaturated lipids decreased with time, and that of the saturated lipids increased. Age comparison on the lipid levels were not studied in the case of Ochromonas. 

Martinez M. Ballabriga A, Gil-Gibernau JJ. Lipids of the developing human retina I. Total fatty acids, plasmologens, and fatty acid compostition of ethanolamine and choline phosphoglycerides. J Neurosci Res 1988- 20 484-490. 

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