Biological activities of the natural antioxidant oleuropein: Exceeding the expectation – A mini-review

• Oleuropein source and biosynthesis.
• Biological activities, potential health benefits and mechanisms of action.
• Oleuropein is a functional ingredient for disease prevention and health promotion.

An emerging body of evidence indicates that oleuropein, a biophenol usually found in olive leaves, extra-virgin olive oil and in some species of the Oleaceae family has potent biological and pharmacological properties. Its main pharmacological activities such as anticancer, cardioprotective, neuroprotective, gastroprotective, hepato-protective, anti-diabetes, anti-obesity and radioprotective, among others, are in large part attributed to its putative antioxidant and anti-inflammatory effects. This mini-review collects and discusses the scattered data available in the literature concerning oleuropein and/or oleuropein-rich extracts and highlights its chemistry, biosynthesis, biological activities and its possible mechanisms of action.