Antibacterial effects of Thymbra spicata L. extracts on Escherichia coli O157:H7, Salmonella enterica subsp. enterica serovar Typhimurium and Campylobacter jejuni

In this study, the antibacterial effects of extracts acquired from the leaves of zahter (Thymbra spicata L.) plant, a traditional thyme, were investigated on Escherichia coli O157:H7, Salmonella enterica subsp. enterica serovar Typhimurium, and Campylobacter jejuni that may cause various damages to human health. For this purpose, diffusion disc assays were performed. Each of the diffusion discs was impregnated with 10 μL of 3 different (10-1, 10-2, and 10-3) dilutions that were diluted from the T. spicata extract homogenates. These discs were placed on the media that was previously cultured with E. coli O157:H7, S. enterica subsp. enterica serovar Typhimurium, and C. jejuni and growth behaviors of each bacteria were observed. According to the obtained results, both E. coli O157:H7 and S. enterica subsp. enterica serovar Typhimurium presented large inhibition zones to 10-1 and 10-2 dilutions (for E. coli O157:H7 21.3±1.7 and 17.7±1.3, respectively; and for S. enterica subsp. enterica serovar Typhimurium: 26.3±1.7 and 20.7±1.3, respectively) but low inhibition zones to 10-3 dilution (8.3±2.1 and 10.0±0.8, respectively). It was observed that the C. jejuni strain formed zones all below 17 mm in all three different dilutions