Oleocanthal (OC), chemically known as 2-(4-hydroxyphenyl)ethyl (E,3R)-4-formyl-3-(2-oxoethyl)hex-4-enoate, is a rare polyphenol found in olive oil, constituting only about 10% of its composition. First discovered in 1992, this compound is garnering significant scientific interest due to its promising biological activities, particularly in cancer and nutrition research. An increasing body of evidence highlights the antioxidant, antimicrobial, anti-inflammatory, and antiproliferative properties of OC, making it an ideal candidate for dermatological applications, especially in the treatment of problematic skin conditions such as eczema and psoriasis.

The aim of this project is to elucidate the biochemical properties of oleocanthal, focusing on its effects on cell proliferation, cytotoxic profile, and its antioxidant, antimicrobial, anti-inflammatory, and wound healing properties, which could be beneficial in the treatment of various skin conditions. Our experiments utilized two human keratinocyte cell lines, HaCaT and CCD1106 KERTr. The results demonstrated a decrease in cell proliferation without compromising cell viability, suggesting that oleocanthal can act as an effective antiproliferative agent. Specifically, over a 96-hour assay, a deceleration in the growth of HaCaT cells was observed when dosed with micromolar concentration, reinforcing the potential of oleocanthal as a therapeutic agent for skin conditions such as psoriasis, where the high proliferation of keratinocytes is the main driving cause of the disease. OC displayed no toxicity on cell viability when dosed at high concentrations. In addition, an antioxidant assay using 1,1-Diphenyl-2-Picrylhydrazyl Radical (DPPH) has shown that OC has strong antioxidant activities at low doses. The antioxidant activities were further corroborated in vitro using HaCaT and CCD1106 KERTr cell lines challenged with hydrogen peroxide. OC clearly demonstrated its ability to protect the cells from the noxious oxidant activity of the peroxidase. The antimicrobial efficacy of oleocanthal was evaluated against four skin non-pathogenic bacterial strains. Results showed that it displayed clear antimicrobial activity.

This study offers promising evidence of the benefits of oleocanthal that can be applied as a cosmetic ingredient in formulations for both normal and injured skin. Further research through more extensive in vitro studies and skin disease models is warranted to fully understand the potential of the compound.