Phenolic compounds of olives and olive oil and their bioavailability

This chapter reviews the current knowledge on the phenolic compounds present in olive and olive oil as well as the bioavailability of these compounds. The majority of studies regarding the bioavailability of olive and olive oil phenolics have focused on three major phenolics: hydroxytyrosol, tyrosol, and oleuropein. In general, these phenolics from olive and olive oil have been demonstrated to be readily bioavailable. The chapter discusses in vivo and in vitro studies regarding the bioavailability of olive and olive oil phenolics. Direct evidence on bioavailability of olive and olive oil phenolics has been achieved by measuring the concentration of the polyphenols and their metabolites in biological fluids, mainly plasma and urine, after ingestion of pure compounds or olive oil, either pure or enriched with the phenolics. The polarity of the phenolic compounds has been suggested to play an important role in the absorption of the phenolic compounds.