Effect of novel synthesised policosanyl phenolates on lipid oxidation

Abstract

Lipophilic derivatisation of phenolic acids could greatly improve their antioxidant activities and solubility in hydrophobic environments, broadening their applications in food, pharmaceutical, and cosmetic industries. In this study, we conducted enzymatic lipophilisation of eight phenolates with policosanols. Vinyl phenolates were used as intermediates to improve the efficiency of enzymatic lipophilisation; and the yields of policosanyl phenolates were in the range of 1.32–20.58%. The antioxidant activities of the resulting phenolipids were compared using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assay and linoleic acid peroxidation ferric thiocyanate assay. The synthesised policosanyl phenolates showed lower ABTS radical scavenging capacities (IC<sub>50</sub>s > 15 mM); whereas they showed high lipid peroxidation inhibitory activities (IC<sub>50</sub>s of peroxidation value < 0.25 mM). The lipid oxidation inhibitory activities of policosanol phenolates were further evaluated using the total oxidation value in a linoleic acid model system and the thiobarbituric acid reactive substances value in a cooked pork model system. Finally, policosanyl 4-hydroxybenzoate, policosanyl syringate, and policosanyl 4-hydroxyphenylacetate showed the highest inhibition effects on lipid oxidation and a potential for use as lipid antioxidants.