Digestive stability of hydroxytyrosol, hydroxytyrosyl acetate and alkyl hydroxytyrosyl ethers

Int J Food Sci Nutr. 2012 Sep;63(6):703-7. doi: 10.3109/09637486.2011.652943. Epub 2012 Jan 24.

Abstract

The digestive stability of two natural antioxidant compounds present in virgin olive oil, hydroxytyrosol (HTy) and hydroxytyrosyl acetate (HTy-Ac) and a new series of hydroxytyrosyl ethers (methyl, ethyl and butyl hydroxytyrosyl ethers) was evaluated by a simulated digestion procedure. High recovery of all compounds after gastric digestion was obtained, although they showed a statistically significant lower stability after pancreatic-bile salts digestion. HTy-Ac was partially hydrolyzed into free HTy, whereas after intestinal digestion, HTy was converted into 3,4-dihydroxyphenyl acetic acid (DOPAC), and HTy-Ac was hydrolyzed to HTy and subsequently transformed into DOPAC. In contrast, no chemical modification of hydroxytyrosyl ethers during in vitro digestion was observed. In summary, HTy, HTy-Ac and hydroxytyrosyl ethers show high and interesting digestive stability and the new synthetic hydroxytyrosyl ethers showed enhanced chemical stability compared to HTy and HTy-Ac.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3,4-Dihydroxyphenylacetic Acid / chemistry
  • Acetates / chemistry*
  • Antioxidants
  • Bile Acids and Salts / chemistry*
  • Catechols / chemistry*
  • Ethers / chemistry*
  • Hydrolysis
  • Molecular Structure
  • Olive Oil
  • Pancreatin / chemistry*
  • Pepsin A / chemistry*
  • Phenylethyl Alcohol / analogs & derivatives*
  • Phenylethyl Alcohol / chemistry
  • Plant Oils / chemistry

Substances

  • Acetates
  • Antioxidants
  • Bile Acids and Salts
  • Catechols
  • Ethers
  • Olive Oil
  • Plant Oils
  • hydroxytyrosyl acetate
  • 3,4-Dihydroxyphenylacetic Acid
  • 3,4-dihydroxyphenylethanol
  • Pancreatin
  • Pepsin A
  • Phenylethyl Alcohol