at 25 °C for 18 h the growth of the bacteria was examined. The MIC was calculated as the lowest concentration of the herb extract that resulted in the absence of visually detectable growth. Each MIC was determined from three experiments. The herb extracts with the MIC values of 500 μg/
mL or more, 250 μg/mL and 125 μg/mL or less were declared to have weak, moderate and strong antimicrobial activities, respectively.