Oleic acid is a naturally occurring monounsaturated fatty acid found in animal and vegetable oils and can be obtained through many food sources, including cooking oils, meats (such as beef, chicken, and pork), cheese, nuts, sunflower seeds, eggs, pasta, milk, olives, and avocados. The U.S. Food and Drug Administration (FDA) has determined that there is credible evidence to support a qualified health claim that consumption of oleic acid in cooking oils (such as olive oil, sunflower oil, or canola oil) may reduce the risk of coronary heart disease.

In addition, oleic acid has been shown to have a variety of pharmacological effects. Studies have found that oleic acid is effective on both cell adhesion and invasion in terms of colony counts in cell cultures treated with 0.156 μg/ml oleic acid. In addition, mucus production was significantly inhibited in bacterial cultures treated with oleic acid. Oleic acid prevents cell attachment to bacteria and has an inhibitory effect on bacterial virulence. This activity of oleic acid may be due to its regulatory effects on cellular processes, while its virulence against bacteria may be related to its effects on bacterial metabolism.

Physiological concentrations of oleic acid inhibit C5a-induced myeloperoxidase release from neutrophils. Inhibition was immediate upon addition of oleic acid, was dependent on D5a, reached saturation, and was greater at lower C5a concentrations. Kinetic analysis of the 1/myeloperoxidase release curve versus the 1/[C5a] curve in the presence of oleic acid was consistent with a synergistic mode of interaction. The inhibitory effect persisted after repeated washing of cells preincubated with oleic acid. The effect of oleic acid was not specific to C5a-induced neutrophil activation; oleic acid also inhibited myeloperoxidase release induced by the Ca2+ ionophore A-23187, as well as serum-induced chemotaxis activated by zymosan. In an experiment to identify the site of action of oleic acid on neutrophil activation, an intracellular oleic acid-binding protein (Mr + 13 000) was isolated. The results suggest that acute changes in plasma fatty acid levels may have a major impact on neutrophil function under physiological conditions.

References:

[1] YAPRAK E, DURAN N. Activity of Oleic Acid on Biofilm Formation of S. aureus[J]. Proceedings of the 9th International Conference on Advanced Materials and Systems, 2022, 1 1: 0. DOI:10.24264/icams-2022.iii.21.

[2] ABD AL-ROOF HIGAZI  Iyad I B. Regulation of neutrophil activation by oleic acid[J]. Biochimica et biophysica acta. General subjects, 1994, 1201 3: Pages 442-446. DOI:10.1016/0304-4165(94)90074-4.