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

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 super(+) 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 super(+) 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 times mL super(-1) and 1.2 to 1.8 mg times mL super(-1), respectively. The results reveal that Algerian olive oils may constitute a good source of antioxidant and antimicrobial agents.Original Abstract: Se ha estudiado la composicion fenolica y las actividades antioxidante y antimicrobiana, contra seis bacterias, de extractos de aceites de oliva de once variedades argelinas. La actividad antioxidante se evaluo mediante la determinacion del efecto captador de radicales de DPPH y ABTS super(+). La actividad antimicrobiana se midio como zona de inhibicion y como concentracion inhibitoria minima (MIC) sobre bacterias perjudiciales humanas y agentes patogenos transmitidos por los alimentos. Los resultados mostraron que los fenoles totales esta significativamente (p< 0,05) correlacionados con DPPH (r = 0,72) y los radicales ABTS + (r= 0,76). Entre las bacterias ensayadas, S. aureus y en menor grado B. subtilis mostraron la mayor sensibilidad; el MIC vario de 0,6 a 1,6 mg[middot]mL super(-1) y 1,2 a 1,8 mg[middot]mL super(-1) respectivamente. Los resultados muestran que los aceites de oliva argelinos pueden constituir una buena fuente de antioxidantes y agentes antimicrobianos.