IN VITRO EVALUATION OF THE ANTIMICROBIAL EFFECT OF EXTRA VIRGIN OLIVE OIL (EVOO) AND OF THE ACTIVE COMPOUNDS HYDROXYTYLSOL AND OLEUROPEIN AGAINST HELICOBACTER PYLORI

SALINAS IBÁÑEZ AG; PENISSI AB; ARISMENDI SOSA AC; VEGA, A.E.

Mar del Plata

Congreso; Reunión Anual de Sociedades de Biociencia SAIC-SAFE- SAB -SAP; 2019

Helicobacter pylori colonize the human gastric mucosa of half of the world´s population. The infection can remain throughout life leading a chronic infection. Eradication therapies involve the use of a proton pump inhibitor and two antibiotics. This not always successful due to the acquired resistance to antibiotics. Natural medicine can provide new compounds that contains active principles with antimicrobial properties. The aim was to evaluate in vitro the antimicrobial effect of extra virgin olive oil (EVOO) and its main phenolic compounds Hydroxytyrosol (H) and Oleuropein (O) against H. pylori. The antibacterial activity against 2 strains of H. pylori (NCTC 11638 and HP661) was evaluated by microbroth dilution assays using Mueller Hinton broth (MHB). 15 µl of 1x108 cfu/ml inoculum of H. pylori strains were added to 100 µl of two-fold dilutions of EVOO, H and O. It was incubated for 24 h at 37°C to determine the minimum concentration of the antimicrobial agent capable of inhibiting growth (MIC). Serial dilutions of Amoxycilin were used as control in the susceptibility test.The antimicrobial effect of EVOO in both strains showed a MIC of 229,5 µg/ml. The compounds separately showed no effect. Interestingly, the combination of both compounds assayed by checkerboard method showed an inhibitory effect at values of H=19,27 µg/ml+O=2,1 µg/ml against NCTC strain, while in 661 strain, the values were H=154,16 µg/ml+O=8,44 µg/ml. The difference observed between both strains could be due to HP661 is resistant to levofloxacin.The compounds used in combination showed synergistic effect against H. pylori strains, this would potentiate the use of the EVOO. However, in this study the MIC of EVOO is higher than the combination of H-O, probably due to other compounds present.This study provides, for the first time, valuable information about the antimicrobial potential of EVOO against H. pylori. Further studies investigating the mechanism of action are needed in order to propose EVOO and its active compounds for antimicrobial therapy.