The Main Phenolic Compounds in Olive Oil and Their Health Benefits

Summary: The main phenolic compounds in olive oil 

The main phenolic compounds in olive oil are tyrosol, hydroxytyrosol, oleocanthal, oleacein, ligstroside, and oleuropein. They are the responsible both for taste (the gustatory aspect) and for health benefits(the therapeutic aspect). Tyrosol and hydroxytyrosol are simple phenols, or phenolic alcohols. Oleuropein is a secoiridoid derivative of hydroxytyrosol. Oleocanthal and oleacein are dialdehydes responsible for the spicy and bitter sensations in high-polyphenol extra virgin olive oil, sensations that signal freshness and quality.

Tyrosol and hydroxytyrosol

Tyrosol is a monophenol, while hydroxytyrosol is an ortho-biphenol or ortho-diphenol. (Note that the terms biphenol and biophenol are not the same.) An ortho-biphenol has two hydroxyl groups on two adjacent carbon atoms in the benzene ring, and these catecholic structures are well known to possess antioxidant activity.

Hydroxytyrosol is one of the most potent antioxidant compounds found in olive oil. Scientific studies have reported that hydroxytyrosol can inhibit the progression of breast cancer cells in laboratory settings. It also scavenges the harmful free radicals that cause several inflammatory diseases.

Oleocanthal (OleoCanthAl): The ibuprofen compound in olive oil

Oleo, from Olea in Latin for Olive oil + Canth, from Kanthos in Greek for stinging + al, chemical suffix for an aldehyde

Oleocanthal is the polyphenol responsible for the peppery, stinging sensation at the back of the throat, the kick that makes a fresh extra virgin olive oil catch in your throat. It is the most studied phenolic compound due to its anti-inflammatory properties and other health effects.

Oleocanthal is not found in meaningful quantities in any other food, not even in the olive fruit itself. It forms only during the extraction process, when ligstroside and its aglycone derivative are converted into oleocanthal in the oil.

Research has shown that oleocanthal produces an anti-inflammatory effect similar to that of ibuprofen, a nonsteroidal anti-inflammatory drug (NSAID).

Oleacein (OleACEin)

Ole, from Olea in Latin for Olive oil + ACE refers to Angiotensin Converting Enzyme + In as in Inhibitor, which suggests its beneficial effects on cardiovascular diseases.

Oleacein is responsible for the bitterness (in Spanish, amargo) of olive oil, perceived at the back of the tongue. This bitterness is a positive quality signal, indicating a fresh, high-polyphenol oil.

It is derived from oleuropein and has a structure very similar to that of oleocanthal. It has been described as an antioxidant, anti-inflammatory, and antimicrobial compound.

Oleacein is the main extra virgin olive oil (EVOO) phenol studied for its therapeutic effect against cardiovascular diseases such as atherosclerosis.

In the stomach, under acidic conditions, it is metabolized by hydrolysis to hydroxytyrosol and elenolic acid.

Oleuropein

Oleuropein and its derivatives also contribute to the bitter sensory perception.

Oleuropein has been studied for a range of potential health benefits, including anti-inflammatory, antioxidant, antimicrobial, anticancer, and neuroprotective effects, with research interest in its potential role in early Alzheimer’s disease.

In the stomach, oleuropein is metabolized through acid-catalyzed hydrolysis. First, the glucose subunit is released, producing an aglycone called oleacein, which then hydrolyzes further into hydroxytyrosol and elenolic acid.

References

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