Antioxidant activity of hydroxytyrosol acetate compared with that of other olive oil polyphenols.
Hydroxytyrosol acetate was synthesized, and the antioxidant activity of this olive oil component was assessed in comparison with that of other olive oil components, namely hydroxytyrosol, oleuropein, 3,4-DHPEA-EA, and alpha-tocopherol in bulk oil and oil-in-water emulsions. The activity of the compounds was also assessed by scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals. Hydroxytyrosol acetate had a weaker DPPH radical scavenging activity than hydroxytyrosol, oleuropein, or 3,4-DHPEA-EA but it had a radical scavenging activity similar to that of alpha-tocopherol. In oil, the antioxidant activity of hydroxytyrosol acetate was much higher than that of alpha-tocopherol or oleuropein, but in an emulsion 3,4-DHPEA-EA and alpha-tocopherol were more effective as antioxidants than hydroxytyrosol acetate. The antioxidant activity of hydroxytyrosol acetate was rather similar to that of hydroxytyrosol in oil and emulsions despite the difference in DPPH radical scavenging activity.
Gordon
M H
MH
Hugh Sinclair Unit of Human Nutrition, School of Food Biosciences, The University of Reading, Whiteknights P.O. Box 226, Reading RG6 6AP, UK. m.h.gordon@reading.ac.uk
Paiva-Martins
F
F
Almeida
M
M
D000085:Acetates / Q000032:analysis / Q000737:chemistry; D000975:Antioxidants / Q000032:analysis* / Q000737:chemistry; D004655:Emulsions; D016166:Free Radical Scavengers; D000069463:Olive Oil; D010636:Phenols / Q000737:chemistry; D010626:Phenylethyl Alcohol / Q000031:analogs & derivatives* / Q000032:analysis* / Q000737:chemistry; D010938:Plant Oils / Q000737:chemistry*; D013997:Time Factors
D000085:Acetates; D000975:Antioxidants; D004655:Emulsions; D016166:Free Radical Scavengers; D000069463:Olive Oil; D010636:Phenols; D010938:Plant Oils; C005975:3,4-dihydroxyphenylethanol; D010626:Phenylethyl Alcohol