Evaluation the antimicrobial activity of Rubia Florida alcoholic extract on some pathogenic bacteria in foods

Utilizing protective and antimicrobial properties of some plants is developing due to the harmful effects of chemical drugs as well as pathogenic bacteria resistant to antibiotics. In this study, Antimicrobial effect of alcholic extract (ethyl asetate) of Rubia Florida on three bacteria (Staphylococcus aureus, Listeria monocytogenes, and Escherchia coli) were evaluated using Micro Well Dilution and Disc Diffusion methods. Also Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of all extracts were determined using Micro-Broth dillusion method. Based on obtained results, for all studied bacteria, no inhibition zones were observed in Micro Well Dilution method. When Disc Diffusion method applied, no significant difference was observed between Staphylococcus aureus and Listeria monocytogenes inhibition zone diameters where there is no inhibition zone for Escherchia coli. Minimum and maximum of MIC was obtained for Listeria monocytogenes and Escherchia coli respectively and no significant differences were observed between MBC of three bacteria. In general, gram positive bacteria were more sensitive to ethyl asetate extract of Rubia Florida than gram negative ones so it could be used against gram positive bacteria in food products.