Triacylglycerol stereospecific analysis

Breckenridge, W. C. 1978. Stereospecific analysis of triacylglycerols. In Handbook of Lipid Research, Vol. I Fatty Acids and Glycerides. A. Kuksis (Editor). Plenum Press, New York pp. 197-232. 

Myher, J.J., Kuksis, A., Gehr, K., Park, P.W. and DiersenSchade, D.A. (1996) Stereospecific analysis of triacylglycerols rich in long-chain polyunsaturated fatty acids. Lipids, 31, 207—215. 

Fig. 5. The stereospecific analysis of triacylglycerols. (From Gurr and James, 1980, reproduced by permission of Associated Book Publishers Ltd.)...

Takagi, T. and Ando, Y. (1995) Stereospecific analysis of monounsaturated triacylglycerols in cocoa... 

Table 4.7 Triacylglycerol stereospecific analysis of evening primrose and borage oils...

Stereospecific analysis of milk fat fractions containing triacylglycerols of different molecular weight have shown that, for fatty acids of chain length C4 to Ci6, the general pattern of fatty acid distribution in normal milk fat is similar to the pattern of distribution in the triacylglycerol fractions of different... 

Most natural triacylglycerols do not have a random distribution of fatty acids on the glycerol backbone. In plant oils, unsaturated acids predominate at the sn-2 position, with more saturated acids at sn-l and sn-3. The distribution of fatty acids at the sn-l and sn-3 positions is often similar, although not identical. However, a random distribution between these two positions is often assumed as full stereospecific analysis is a time-consuming specialist procedure. In animal fats, the type of fatty acid predominating at the sn-2 position is more variable for example, palmitate may be selectively incorporated as well as unsaturated acids (Table 5). 

On the other hand, the specificities of hPL and RmL are very low. RmL strongly favors positions 1 and 3 (rather independent of the type of the fatty acid) in triacylglycerols. To date it is the only lipase that has been crystallized in a complex with an inhibitor containing a short aliphatic chain (Brzozowski et al., 1991). However, the low resolution of the study does not allow for a detailed description of the molecular basis of substrate specificity. Also, no structure-based analysis of stereospecificity in lipases is possible results of purely chemical studies (Kaz-lauskas et al., 1991, and references therein Xie et al., 1990) fall outside the scope of this review. 

Santinelli, F., Damiani, R and Christie, W.W. (1992) The triacylglycerol structure of olive oil determined by silver ion high performance liquid chromatography in combination with stereospecific analysis. J. Am. Oil Chem. Soc., 69, 552-557. 

Harp, T.K. E.G. Hammond. Stereospecific analysis of soybean triacylglycerols. Lipids 1998, 33, 209-216. 

Procedures for pancreatic lipase use are described by Jensen and Pitas (1976) and for lipoprotein, lingual and hepatic lipases by Paltauf et al, (1974). Stereospecific analysis of fatty acids in triacylglycerols has been fully discussed by Brecken-ridge (1978). 

Of the other triacylglycerols, 12% contain two saturated and one nnsatu-rated fatty acid, while only 4% contain two nnsatnrated and one satnrated fatty acid. Based on equivalent carbon number (ECN), the major triacylglycerol of coconut oil is trilaurin, which is understandable becanse the dominant fatty acid is lauric acid (Lanreles et al., 2002). Stndies on stereospecific analysis, which gives information on the fatty acids attached to the three positions of the glycerol backbone, have been carried ont for coconnt oil. This information is of value for the production of strnctnred lipids (Pham and Gregorio, 2008). 

---