Abstract
Tetraacylglycerol (an acylglycerol estolide) contains an acyl chain attached to the hydroxyl group of another acyl chain attached to the glycerol backbone. Lesquerolic acid (Ls, OH1420:111) is the main fatty acid in lesquerella oil and may be used industrially for the manufacture of biodegradable industrial products. Electrospray ionization mass spectrometry of the lithium adducts of acylglycerols in the high-performance liquid chromatography fractions from the seed oil of lesquerella (Physaria fendleri) was used to identify thirteen tetraacylglycerols. They were LsLsLsLn, LsLsLsL, LsLs-OH20:2-O, LsLsLsO, LsLsLnLn, LsLsLLn, LsLsOLn, LsLsLL, LsLsOL, LsLsOP, LsLsOO, LsLsLS and LsLsOS. The OH20:2 was auricolic acid (OH1420:211,17). For the four tetraacylglycerols containing one normal fatty acid (non-hydroxy fatty acid), LsLsLsLn, LsLsLsL, LsLs-OH20:2-O and LsLsLsO, the normal fatty acids were all directly attached to the glycerol backbone, not to the hydroxyl group of fatty acids. We propose that the biosynthetic precursors (triacylglycerol acyltransferase) of these four tetraacylglycerols were LsLsLn, LsLsL, LsLsO (Ls-OH20:2-O) and LsLsO individually. LsLsO and Ls-OH20:2-O were equally active as the biosynthetic precursors for LsLs-OH20:2-O. For LsLsLS, linoleate were all attached to the glycerol backbone and LsLsL was proposed to be the biosynthetic precursor. For LsLsOS, stearate were all attached to the glycerol backbone and LsLsS was proposed to be the biosynthetic precursor. For the other seven tetraacylglycerols containing two normal fatty acids, LsLsAB, the biosynthetic precursors could be both LsLsA and LsLsB.
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References
Gunstone FD, Alander J, Erhan SZ, McKeonTA LJT (2007) Nonfood uses of oils and fats. In: Gunstone FD, Hardwood JL, Dijkstra AJ (eds) The lipid handbook, 3rd edn. Chapman & Hall, London, pp 591–635
Lin JT, Arcinas A, Harden LR, Fagerquist CK (2006) Identification of (12-ricinoleoylricinoleoyl)diricinoleoylglycerol, an acylglycerol containing four acyl chains, in castor oil by LC-ESI-MS. J Agric Food Chem 54:3498–3504
Lin JT, Turner C, Liao LP, McKeon TA (2003) Identification and quantification of the molecular species of acylglycerols in castor oil by HPLC using ELSD. J Liq Chromatogr Relat Technol 26:773–780
Lin JT, Chen GQ (2012) Identification of minor acylglycerols less polar than triricinolein in castor oil by mass spectrometry. J Am Oil Chem Soc 89:1773–1784
Hayes DG, Kleiman R, Philips BS (1995) The triglyceride composition, structure, and presence of estolides in the oils of Lesquerella fendleri and related species. J Am Oil Chem Soc 73:267–269
Zhang H, Olson DJH, Van D, Purves RW, Smith MA (2012) Rapid identification of triacylglycerol-estolides in plant and fungal oils. Ind Crops Prod 37:186–194
Hayes DG, Kleiman R (1996) A detailed triglyceride analysis of Lesquerella fendleri oil: column chromatographic fractionation followed by supercritical fluid chromatography. J Am Oil Chem Soc 73:267–269
Lin JT, Chen GQ (2013) Identification of TAG and DAG and their FA constituents in lesquerella (Physaria fendleri) oil by HPLC and MS. J Am Oil Chem Soc (accepted, 7/21/2013)
Dierig DA, Tomasi PM, Dahlquist GH (2001) Registration of WCL-Ly2 high oil Lesquerella fendleri germplasm. Crop Sci 41:604–605
Lin JT, Woodruff CL, McKeon TA (1997) Non-aqueous reversed-phase high performance liquid chromatography of synthetic triacylglycerols and diacylglycerols. J Chromatogr A 782:41–48
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Lin, JT., Chen, G.Q. Identification of Tetraacylglycerols in Lesquerella Oil by Electrospray Ionization Mass Spectrometry of the Lithium Adducts. J Am Oil Chem Soc 90, 1831–1836 (2013). https://doi.org/10.1007/s11746-013-2332-y
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DOI: https://doi.org/10.1007/s11746-013-2332-y