Antimicrobial and antioxidant activities of Turkish extra virgin olive oils.
Turkish extra virgin olive oils (EVOO) from different varieties/geographical origins and their phenolic compounds were investigated in terms of their antimicrobial and antioxidant properties in comparison to refined olive, hazelnut, and canola oils. Antimicrobial activity was tested against three foodborne pathogenic bacteria, Escherichia coli O157:H7, Listeria monocytogenes , and Salmonella Enteritidis. Although all EVOOs showed a bactericidal effect, the individual phenolic compounds demonstrated only slight antimicrobial activity. Moreover, refined oil samples did not show any antimicrobial activity. Among the phenolic compounds, cinnamic acid (2 mg/kg of oil) had the highest percent inhibition value with 0.25 log reduction against L. monocytogenes. The synergistic interactions of tyrosol, vanillin, vanillic, and cinnamic acids were also observed against Salmonella Enteritidis. The antioxidant activities of oils were tested by beta-carotene-linoleate model system and ABTS method. In both methods, EVOOs showed higher antioxidant activities, whereas refined oils had lower activity. The ABTS method provided a higher correlation (0.89) with total phenol content.
Karaosmanoglu
Hande
H
Biotechnology and Bioengineering Program, Izmir Institute of Technology, Urla-Izmir, Turkey.
Soyer
Ferda
F
Ozen
Banu
B
Tokatli
Figen
F
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000975:Antioxidants / Q000032:analysis*; D001419:Bacteria / Q000187:drug effects; D000069463:Olive Oil; D010636:Phenols / Q000494:pharmacology; D010938:Plant Oils / Q000737:chemistry*; D014421:Turkey
D000900:Anti-Bacterial Agents; D000975:Antioxidants; D000069463:Olive Oil; D010636:Phenols; D010938:Plant Oils