Antioxidant activity of monooleyl and dioleyl p-coumarates in in vitro and biological model systems.

Lipase-catalysed acidolysis of p-coumaric acid with triolein was carried out, followed by separation of the synthesized phenolipids using column chromatography. The identification of synthesized phenolipids was conducted by using HPLC-MS. The antioxidant activities of the purified phenolipids were assessed in in vitro assays and biological systems. Monooleyl and dioleyl p-coumarates were identified as the phenolipid species present. The prepared phenolipids exhibited varying antioxidant activities in 1,1-diphenyl-2-picrylhydrazyl (DPPH) and peroxyl radical scavenging, reducing power, β-carotene/linoleate bleaching, human low-density lipoprotein (LDL) cholesterol oxidation as well as hydroxyl and peroxyl radical-induced DNA cleavage assays. Practical applications: In this study, the antioxidant activity of synthesized phenolipids, monooleyl and dioleyl p-coumarates obtained from p-coumaric acid and triolein, was investigated and confirmed in a number of commonly employed assays. The synthesized model phenolipids containing p-coumaric acid moiety and fatty acid chains exhibited improved lipophilicity and antioxidant activity. Extension of this work to marine omega-3 oils as starting materials is expected to produce novel phenolipids that may be used as nutraceuticals and functional food ingredients with unique stability characteristics and potentially improved health benefits. [ABSTRACT FROM AUTHOR]