RESUMO
Three extracts originating from a combination of various Latvian plant species were tested for their antibacterial activities by evaluating growth delays using a fully automated microturbidimetric method. Ten different human and bovine strains of the genera Staphylococcus and Micrococcus were used as test microorganisms. The inhibitory effect in vitro was defined as the difference between the growth rate without herbs and the growth rate in the presence of an extract. Among the tested strains, Staphylococcus aureus was found sensitive to all 3 extracts. However, extract I was the most effective in slowing the growth of all strains tested. Using appropriate tester strains it should be possible to set up a broad-range microtubidimetry assay for individual herb screening in vitro. The hemolytic effects of the individual extracts on human erythrocytes were also studied at different concentrations. Two of the herbal extracts had minimal lytic effects on eurocaryotic cells. An additional hemolysis test was conducted in the presence of coenzyme Q10 (CoQ10) as a free radical scavenger: CoQ10 had no effect on the hemolytic reaction.