In vitro antimicrobial activity of four Slovak medicinal plants against different strains of bacteria

Medicinal plants are traditionally used for the treatment in human medicine. The antibacterial activity of ethanol extract of four plant species (Achillea millefolium L., Agrimonia eupatoria, Melissa officinalis and Tilia platyphyllos) applied in the traditional medicine in Slovakia were tested. Extracts of certain parts of these plants were tested in vitro against six bacterial species (Bacillus cereus, Enterococcus faecalis, Escherichia coli, Lactobacillus brevis, Lactobacillus hilgardii and Serratia rubidea) strains using the disc diffusion method and microbroth dilution method. Minimum inhibitory concentrations for the extracts against all the microorganisms were determined by serial dilutions. All the extracts demonstrated antibacterial activity against Gram-positive bacteria and partially against Gram-negative bacteria.