Lipophilic hydroxytyrosyl esters. Antioxidant activity in lipid matrices and biological systems.
Antioxidant activities of lipophilic hydroxytyrosyl acetate, palmitate, oleate, and linoleate were compared with those of hydroxytyrosol, alpha-tocopherol, and butylhydroxytoluene (BHT) in both glyceridic matrix and biological systems. Aliquots of a glyceridic matrix spiked with various concentrations of antioxidant were subjected to accelerated oxidation in a Rancimat apparatus operated at 90 degrees C. The relationships between induction time (IT) and antioxidant concentration (mmol/kg) presented by hydroxytyrosol and hydroxytyrosyl acetate, palmitate, oleate, and linoleate were similar. Hydroxytyrosol and its esters showed greater antioxidant activity than alpha-tocopherol or BHT. We also evaluated the capacity of hydroxytyrosyl esters to protect proteins and lipids against oxidation caused by peroxyl radicals, using a brain homogenate as an ex vivo model. All tested compounds showed a protective effect in these systems, which was greater in preventing the generation of carbonyl groups in protein than of malondialdehyde in lipid. Inclusion of a lipophilic chain in the hydroxytyrosol molecule enhanced its antioxidant capacities in this biological model.
Trujillo
Mariana
M
Departamento de Química Organica y Farmacéutica and Departamento de Bioquímica, Facultad de Farmacia, Universidad de Sevilla, C/Prof. García Gonzalez 2, 41012 Sevilla, Spain.
Mateos
Raquel
R
Collantes de Teran
Laura
L
Espartero
José L
JL
Cert
Rosa
R
Jover
Maria
M
Alcudia
Felipe
F
Bautista
Juan
J
Cert
Arturo
A
Parrado
Juan
J
D000085:Acetates / Q000494:pharmacology; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001921:Brain / Q000378:metabolism; D002084:Butylated Hydroxytoluene / Q000494:pharmacology; D004952:Esters / Q000494:pharmacology*; D019787:Linoleic Acid / Q000494:pharmacology; D015227:Lipid Peroxidation / Q000187:drug effects; D019301:Oleic Acid / Q000494:pharmacology; D010168:Palmitates / Q000494:pharmacology; D010626:Phenylethyl Alcohol / Q000031:analogs & derivatives* / Q000494:pharmacology; D011506:Proteins / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D024502:alpha-Tocopherol / Q000494:pharmacology
D000085:Acetates; D000975:Antioxidants; D004952:Esters; D010168:Palmitates; D011506:Proteins; C005975:3,4-dihydroxyphenylethanol; D002084:Butylated Hydroxytoluene; D019301:Oleic Acid; D019787:Linoleic Acid; D024502:alpha-Tocopherol; D010626:Phenylethyl Alcohol