Triglycerides, iodinated

Fatty acid No. C atoms No. double bonds Mol. wt.of acid Mol. wt. of triglyceride Saponification value of triglyceride Iodine value of acid Iodine value of triglyceride... 

Infrared spectra of fats and oils are similar regardless of their composition. The principal absorption seen is the carbonyl stretching peak which is virtually identical for all triglyceride oils. The most common appHcation of infrared spectroscopy is the determination of trans fatty acids occurring in a partially hydrogenated fat (58,59). Absorption at 965 - 975 cm is unique to the trans functionaHty. Near infrared spectroscopy has been utilized for simultaneous quantitation of fat, protein, and moisture in grain samples (60). The technique has also been reported to be useful for instmmental determination of iodine value (61). 

The iodine number is an indication of the degree of unsaturation of triglycerides, and is the amount of iodine (in mg) required to react with 1 g of lipid material. 

The oils from which factices are manufactured are unsaturated vegetable and animal oils, which react with sulphur. Fatty oils with iodine number greater than 80 (iodine number is defined as the number of grammes of iodine absorbed by 100 g of fat/oil) are generally used, i.e., oils with three or more double bonds per triglyceride molecule. Rapeseed oil is the most common oil used for general purpose grades and castor oil is used for oil resistant factice. Other oils are used in preference by other countries due to local availability and cost. 

Catalytical studies of synthesized products were tested according to the Hanus Method [18]. Since Triglycerides (fats and oils) are esters of glycerol with three fatty acids. These long chain fatty acids may contain one or more double bonds. With no double bonds, the fatty acid is termed saturated (with hydrogen), and with double bonds, it is termed unsaturated. The iodine number is an indication of the degree of unsaturation of the oil (Scheme 14.4). 

Fig. 12. Structures of iodinated triglycerides with two triiodobenzene groups [71]... 

The basis for contrast agents derived from nutrional products was Intralipid, which had been prepared from phospholipids obtained from soy bean oil and egg yolk [86]. Intralipid was chemically modified by iodination into Intraiodol, which contained 50 mgl mbThe particles formed in the emulsion were mostly taken up by the hepatocytes and to a lesser extent by the RES [87,88]. Intraiodol was better tolerated than EOE-13 or its precursor, AG 60.99. The addition of cholesterol to Intraiodol resulted in NRI 757 with an iodine concentration of 42 mg mL b Further modifications by replacing the iodinated triglycerides of Intraiodol by ethiodized poppy seed oil and reducing the cholesterol content to... 

Iodine values in pure systems (Table D1.4.3) have been reported, and it can be seen that within sets of triglycerides with fatty acids of about the same or with the same chain lengths but with increasing numbers of double bonds, there is an increase in IV. However, within a series of triglycerides with increasing chain lengths (from 10 to 24) with one double bond,... 

Iodine and saponification numbers are often determined in industries concerned with lipid products. The iodine number is defined as the number of grams of iodine (I2) that reacts with 100 g fat. The saponification number is mg KOH required to hydrolyze 1 g triglyceride. Now suppose that you have 5 g triglyceride and it required 980 mg KOH for hydrolysis and 4.45 g I2 to react with the unsaturated fatty acids therein. Calculate or determine the following ... 

Table 2-18 Triglycerides and Phospholipids of Mackerel Lipids and Calculated Iodine Values for Methyl Esters of Fatty Acid from Lipids...

When the hydrogenation function is embedded in the crystal voids of an MFI topology, the formation of trans-isomers is strongly reduced. After partial reduction of soy bean oil with such catalyst from an iodine value of 140 to 80, virtually no trans-isomers are obtained (56). This is the result of pore mouth catalysis combined with zeolite shape selectivity. Due to the bent character of the cts-isomer chains in triglycerides, trans-configured chains preferentially enter the pore mouths for hydrogenation. In this environment, metal-catalyzed cis-trans isomerization is restricted for steric reasons as multiple readsorption is minimal. 

The olive oil described in the previous problem was reacted with iodine. Exactly 578 mg of I2 were absorbed by 680 mg of the oil. (a) On the average, how many double bonds are present in a molecule of triglyceride (b) What is the iodine number of the oil ... 

Microemulsions of a series of polyiodinated triglycerides (ITG), labeled with iodine-125 and processed in a microfluidizer,were investigated for their contrast enhancement of the liver and the tumor in normal and tumor-bearing (Walker 256) rats, in rabbits bearing VX2 carcinoma, and in normal dogs in CT (911). The mean particle diameter of microemulsions was less than 300 nm. These preparations were stable and autoclavable. Thirty minutes after intravenous injection, from 66 to 78% of the injected dose remained in the liver of the rats. After 3 h the liver still retained from 46% to 93% of the dose. At dose levels ranging from 20 to 70 mg I/kg, the increase in density was reported to be about 40 HU in the rats. In a female pig, the contrast enhancement within 1 h of injection was 90 HU. The liver uptake of ITGs was partially dependent on the formulation vehicle, but the metabolism and clearance from the liver were... 

The melting point of a triglyceride decreases with an increase in double bonds or unsaturation. The iodine number is a measure of unsaturation. Therefore the higher the iodine number, the lower the melting point. 

Several examples are given. Free fatty acids present in the feed oil are reduced by 95 %, and the iodine number (a measure of unsaturation) is reduced from 191 to 66. Furthermore the melting point of the triglyceride is increased from -2 °C to 34 °C indicating that substantial hydrogenation occurred. 

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