Conjugated Linoleic Acid-Rich Soy Oil Triacylglycerol Identification

by Lall, Rahul K.; Proctor, Andrew; Jain, Vishal P.; Lay, Jackson O.

Conjugated linoleic acid (CLA)-rich soy oil has been produced by soy oil linoleic acid (LA) photoisomerization, but CLA-rich oil triacylglycerol (TAG) characterization was not described. Therefore, the objectives were to identify and quantify new TAG fractions in CLA-rich oil by nonaqueous reversed-phase high-performance liquid chromatography (NARP-HPLC). Analytical NARP-HPLC with an acetonitrile/dichloromethane (ACN/DCM) gradient and an evaporating light scattering detector/ ultraviolet (ELSD/UV) detector was used. New TAG peaks from LA-containing TAGs were observed. The LnLL, LLL, LLO, and LLP (Ln, linolenic; L, linoleic; O, oleic; and P, palmitic) peaks reduced after isomerization with an increase in adjacent peaks that coeluted with LnLnO, LnLO, LnOO, and LnPP. The newly formed peaks were wider than those of the original oil and absorbed at 233 nm, suggesting the possibility of various CLA containing TAGs. The HPLC profile showed five fractions of mixed TAGs, and fatty acid analysis showed that CLA isomers were found predominately in fractions 2 and 3, which originally contained most LA. The CLA isomers were 70-80% trans,trans and 20-30% cis, trans and trans,cis.

Journal
Journal of Agricultural and Food Chemistry
Volume
57
Issue
5
Year
2009
Start Page
1727-1734
URL
https://dx.doi.org/10.1021/jf803111e
ISBN/ISSN
1520-5118; 0021-8561
DOI
10.1021/jf803111e