Triacylglycerol molecular species

Abbreviations nr, not reported US, US hybrids Int, International hybrids 16 0, palmitic acid 18 0, stearic acid 20 0, arachidic acid 18 1, oleic acid 18 2, linoleic acid 18 3, linolenic acid and RBD, refined, bleached, and deodorized oil. 

CHPLD-Flame Ionization Detector Values from Byrdwell et al. 2001. Abbreviations Ln, linolenic acid L, linoleic acid O, oleic acid S, stearic acid P, palmitic acid. Symbols such as LOS refer to all the possible triacylglycerols containing these three acids. 

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TABLE 6. Quantitative Anaiysis of Triacylglycerol Molecular Species in Refined Corn Germ Oil. 

Table 10.3 Triacylglycerol molecular species in refined corn germ oil...

J. E. Staggers, G. J. P. Femando-Wamakulasuriya, M. A. Wells. Studies on fat digestion, absorption and transport in the suckling rat. 11. Triacylglycerols molecular species. slereospeciftc analysis and specificity of hydrolyses oflingual lipase, i Lipid Res 22 675-679, 1981. 

Yoshida, H Yoshida, N Tomiyama, Y Mizushina, Y. Charaeteristies of lipid components, fatty acid distributions and triacylglycerol molecular species of adzuki beans (Vigna angularis). Food Chemistry, 2009, 115,1424-1429. 

Detection of the abundance of diacylglycerol and triacylglycerol molecular species in cells using neutral loss mass spectrometry. Anal. Biochem. 366, 59-70. 

Triacylglycerols. The composition of TGs refers to their structure or the identity of the fatty acids esterified to each of the three hydroxyls on glycerol and ultimately to the identity of the individual molecular species. Because there may be over 400 fatty acids in a milk sample, based on random distribution, there may be a total of 4003 or 64 x 106 individual TGs, including all positional and enantiomeric isomers. A random distribution is defined as all possible combinations resulting from expansion of the binomial equation. If we have two fatty acids, x and y, located at random in the three positions of glycerol, the equation becomes (x + y)3 or x3 + 3x2y + 3 xy2 + y3, which, when expanded further, is x3 = xxx, 3x2y = xxy, 3 xy2 = yyx, y3 = yyy yxx xyy... 

Silver ion chromatography is a useful technique for separating geometrical isomers of fatty acids (as the methyl ester derivatives) for subsequent analysis by GC. On the other hand, a stable ion-exchange column loaded with silver ions has been developed for HPLC that has proved of value in the simplification of complex mixtures of fatty acids (FAs) of natural origin for subsequent identification by GC-MS and for separating molecular species of triacylglycerols (41). 

Milk fat has presented a particular challenge to analysis in terms of the identification and separation of TGs due to their complex variety of molecular species. The most complex mixtures of natural triacylglycerols require HPLC with gradient elution. 

The purpose of their investigation was to determine the relative order of elution of the molecular species of rearranged butterfat triacylglycerols for which the exact quantitative composition can be calculated by statistical considerations. The initial part of the study was concerned with verifying that a random distribution of the fatty acids had indeed been obtained, which was established by detailed GC and HPLC resolution and MS identification of the species. 

Gresti, J., Bugaut, M., Maniogui, C., Bezard, J. 1993. Composition of molecular species of triacylglycerols in bovine milk fat. J. Dairy Sci., 76, 1850-1869. 

TABLE 4. Molecular Species of Triacylglycerols Containing only Palmitic and Oleic Acid. 

TABLE 5. Contrasting Triacylglycerol Composition of Some Commodity Oils [Molecular Species (wt%)]. 

Triacylglycerols are the most abundant lipid class found in canola oil. The combination of fatty acids on the glycerol moiety represent the most complex mixture with n possible molecular species, where n is the number of fatty acids present in the oil. 

The fatty acid composition of rice bran oil is most similar to peanut or ground nut oil (Table 14) (8). Palmitic, oleic, and hnoleic acids make up more than 90% of the fatty acids present. The major molecular species of triacylglycerols are palmi-tic-linolenic-oleic, oleic-linoleic-palmitic, pahnitic-hnoleic-linoleic, hnolenic-lino-leic-palmitic, and trioleic. As with peanut oil, rice bran oil is most suited for general frying and cooking applications. 

Yoshida, H. Y. Tomiyama S. Kanrei Y. Mizushina. Tocopherol distribution and molecular species of triacylglycerols in soybean embryonic axes. /. Am. Oil Chem. Soc. 2006b, 83, 345—351. 

Ricinoleate (R) has many industrial uses. Its only commercial source is castor oil, in which ricinoleate constitutes 90% of the fatty acids (FA) (1). Castor beans contain toxic substances and are hazardous to grow, harvest, and process. Therefore, it is desirable to produce ricinoleate from a transgenic plant lacking these toxic substances. To develop a transgenic plant capable of producing a high level of ricinoleate in its seed oil, it is essential to understand the biosynthesis of castor oil. We previously established the biosynthetic pathway of castor oil and identified the key enzymatic steps of the pathway, which drive the ricinoleate into castor oil (2,3). We report here the identification and quantification of the molecular species of triacylglycerols (TAG, end products), phosphatidylcholines (PC, intermediate) and phosphatidylethanolamines (PE, intermediate) on the pathway incorporated from various [ C]-labeled FA and the comparison of the levels of their incorporation. 

Incorporation of Various Radiolabeled Fatty Acids (FA) into Molecular Species of Triacylglycerols (TAG) and Diacylglycerols (DAG) in Castor Microsomal Incubations (60 min)... 

Molecular Species of Triacylglycerols (in mole %) of Mustard Seed Oil ... 

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