ARS | Publication request: Preservation of polyunsaturated fatty acyl glycerides via intramolecular antioxidant coupling

Submitted to: Chemistry and Physics of Lipids
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 10, 2012
Publication Date: June 1, 2012
Citation: Laszlo, J.A., Evans, K.O., Compton, D.L. 2012. Preservation of polyunsaturated fatty acyl glycerides via intramolecular antioxidant coupling. Chemistry and Physics of Lipids. 165:530-536.

Interpretive Summary: A new plant oil derivative was found to have excellent stability so that it may be useful for delivering healthful fatty acids to human skin. Our mission is to develop new, value added uses for crop oils for the development of domestically-derived, bio-based products. The newly developed feruloyl-di-gamma-linolenoylglycerol molecule is made from a vegetable oil and designed for topical delivery of protective essential oils for improved skin health and appearance. In the present research, we demonstrate that this molecule can greatly protect polyunsaturated fatty acids from damage. We observed that this molecule works well to stop the adverse chemical events of free radical oxidation that can lead to the destruction of fatty acids. These findings provide researchers with an enhanced understanding of how such molecules may promote dermal care.

Technical Abstract: Ferulic acid and its esters are known to be effective antioxidants. Feruloyl di-gamma-linolenoylglycerol was assessed for its ability to serve as an antioxidant for preventing the oxidation of its gamma-linolenoyl polyunsaturated fatty acyl groups in model membrane phospholipid vesicles. The molecule was incorporated into single-lamellar vesicles comprised of 1,2-dioleoyl-sn-glycero-3-phosphocholine. Feruloyl di-gamma-linolenoylglycerol was found to be highly resistant to 2,2'-azobis(2-amidinopropane) dihydrochloride-initiated oxidation in comparison to di-gamma-linolenoylglycerol. Analysis of the individual fatty acyl chains indicated that degradation of gamma-linolenoyl groups from feruloyl di-gamma-linolenoylglycerol proceeded much more slowly than loss of the entire molecule, indicating that the feruloyl moiety was preferentially oxidized. In vesicles incorporating di-gamma-linolenoylglycerol and an equal amount (5 mol% each) feruloyl dioleoylglycerol, the extent of gamma-linolenoyl protection was not as great as when the gamma-linolenoyl groups were molecularly combined with a ferulate group. These findings indicate that the ferulate group of feruloyl di-gamma-linolenoylglycerol expresses intramolecular antioxidant activity. Direct coupling of polyunsaturated fatty acids with phenolic antioxidants may improve the oxidative stability of sensitive fatty acids in food or topical uses.