Olea europeae (Oleaceae)

  • The plant

Olea europeae (olive tree) is an evergreen tree or shrub native to the Mediterranean countries, Asia and parts of Africa. It is short and squat, and rarely exceeds 8–15 meters in height. It tolerates shallow, rocky soil, with little fertilizer, and thrives in areas with dry, hot summers epecially in coastal areas.

  • The myth

The olive tree  is known from the ancient times and is being cultivated for more than 7.000 years.
In old testimony it is mentioned that an olive branch was brought by a dove to Noah arc to demonstrate that the flood was over.

According to Greek mythology, the olive tree was Athena’s gift to the people of Attica, when she won the patronage of the city of Athens over Poseidon. As far back as 3000 BC, olives were grown commercially in Crete; and they may have been the source of the wealth of the Minoan Civilization. The age of an olive tree in Crete, claimed to be over 2,000 years old, has been determined on the basis of tree ring analysis.
Over the years, the olive has been the symbol of peace, wisdom, glory, fertility, power and pureness. Many Greek and Roman writings refer to the beneficial properties of the olives, olive oil and extracts of the leaves.

  • Culinary and Ethnopharmacology

After the 16th century, the Europeans brought the olive tree to the New World, and its cultivation began in California, Mexico, Peru, Chile and Argentina. It is estimated that there are about 800 million olive trees in the world today, and the vast majority of them are found in Mediterranean countries.
The olive tree products have many valuable uses to humans. The fruit is rich in oil which is not only used to produce olive oil for cooking, but also used in lubricants for production of soap, in cosmetic industry.

The leaf of olive tree has been used medicinally in various eras and places. The olive leaves and olive leaf extracts, are now marketed as anti-aging, immunostimulators, and even antibiotics. Clinical evidence has proven the blood pressure lowering effects of olive leaf extracts. Pharmacological tests support its antibacterial, antifungal, and anti-inflammatory effects. A liquid extract of fresh olive leaves recently attracted international attention when it was shown to have almost double antioxidant efficacy compared to the green tea extract and 400% higher efficiency than Vitamin C.

Active constituents, Pharmacological properties and traditional medical applications
In 1908, Bourquelot and Vintilesco isolated a bitter glucoside (structurally classified as an iridoid) from olive leaves and named it oleuropein. In 1960, scientists from Holland further isolated elenolic acid (a monoterpene), which was eventually determined to be the chemical constituent with the greatest activity against infectious microbes. Later in that same decade, researchers at a U.S. pharmaceutical company (Upjohn Co., Kalamazoo, MI) demonstrated that elenolic acid exhibited remarkable inhibition of viruses and bacteria without damaging the host cells in vitro.


           Oleuropein                                            Elenolic acid

The olive leaf extracts have been proved so beneficial to human health because of the presence of bioactive constituents such as the antioxidants oleuropein and hydroxytyrosol, the antimicrobial elenolic acid and several polyphenols and flavonoids including oleocanthal.  
Olive leaf products are commonly used to fight common colds and flu, yeast, and viral infections such as the hard-to-treat Epstein-Barr disease, shingles and herpes. Olive leaf reduces the low-density lipoproteins (LDL) lowers the blood pressure, increases blood flow by relaxing the arteries and in general improves condition of the heart.

Olive leaf’s antioxidant properties protect the body from the continuous activity of free radicals. Recent preliminary scientific findings on the olive leaf have shown that its antioxidants to be effective in the treatment of tumors and various types of cancer such as liver, prostate, and breast cancer.
Olive leaf are used for the preparation of liquid concentrates, dry leaf tea, leaf powder, or capsules. The fresh leaf liquid extracts are gaining popularity due to the broader range of bioactive compounds they contain.