Olive oils from Algeria: Phenolic compounds, antioxidant and antibacterial activities

Abstract

The phenolic compositions, antioxidant and antimicrobial activities against six bacteria of phenolic extracts of olive oil varieties from eleven Algerian varieties were investigated. The antioxidant activity was assessed by determining the scavenging effect on the DPPH and ABTS.+ radicals. The antimicrobial activity was measured as a zone of inhibition and minimum inhibitory concentration (MIC) on human harmful and foodborne pathogens. The results show that total phenols was significantly (p < 0.05) correlated with DPPH (r = 0.72) and ABTS.+ radicals (r = 0.76). Among the bacteria tested, S. aureus and to a lesser extent B. subtilis showed the highest sensitivity; the MIC varied from 0.6 to 1.6 mg·mL-1 and 1.2 to 1.8 mg·mL-1, respectively. The results reveal that Algerian olive oils may constitute a good source of antioxidant and antimicrobial agents.