Antibacterial and antifungal activities of Turkish medicinal plants

In this study, the antibacterial and antifungal activities of Rhus coriaria L. (Anacardiaceae), Stachys annua (L.) subsp. annua Ic., Stachys pumilia Banks & Sol., Laurus nobilis L. (Lauraceae), Allium neapolitanum Lyr. (Liliaceae), Salvia viridis L. (Lamiaceae), and Nicotina rustica (Solanaceae) species were investigated. The microbial effects of these plants were tested by a disk diffusion method using Bacillus megaterium DSM 32, Bacillus brevis FMC 3, Bacillus subtilis IMG 22, Bacillus cereus FMC 19, Escherichia coli DM, Enterobacter aerogenes CCM 2531, Pseudomonas aeruginosa DSM 50071, Staphylococcus aureus Cowan 1, Listeria monocytogenes Scott A and Micrococcus luteus LA 2971, Candida tropicalis and Candida albicans CCM 314. The results showed that the fruit extract of R. coriaria had the strongest antimicrobial effect with an inhibition zone of 35-51 nim against all the bacteria used, while S. viridis demonstrated the weakest antibacterial effect, inhibiting only the development of S. aureus, with an inhibition zone of 11 min. A. neapolitanum, L. nobilis and N. rustica extracts were effective only with some yeasts. The growth of S. aureus was inhibited by all the plant extracts except for S. annua subsp. annua, having an inhibition zone ranging from 7-8 mm. With the exception of B. subtilis IMG 22, L. monocytogenes Scott A and M. luteus LA 2971, the growth of the other bacteria was inhibited by all the extracts. Except for the fruit extracts of R. coriaria and A. neapolitanum, all additional extracts of generated inhibition zones smaller than those generated by several reference antibiotics.