Tested bacteria Mean zone of inhibition (mm) ± SD Ginger Black cumin Thyme Clove peppermint Gram-negative: E. coli Pseudomonas aeruginosa 7.30 ± 0.11d 8.00 ± 0.15c 5.30 ± 0.11e 9.50 ± 0.41a 11.30 ± .55b 7.30 ± 0.17d 9.30 ± 0.15c 3.00 ± 0.14e 20.00 ± 0.26a 8.70 ± 0.20b Gram-postive: Bacillus cereus Lactococcus lactis   Listeria monocytogens Staphylococcus aureus 4.30 ± 0.11e 13.00 ± 0.19b 12.30 ± 0.22c 0.00 ± 0.0b 9.30 ± 0.15a 8.30 ± 0.35c 7.00 ± 0.11d 0.00 ± 0.0b 5.60 ± 0.15c 7.00 ± 0.11d 5.60 ± 0.35e 0.00 ± 0.0b 5.00 ± 0.20d 5.00 ± 0.16e 14.30 ± 0.22a 4.00 ± 0.18a 7.00 ± 0.10b 19.50 ± 1.00a 13.00 ± 0.30b 0.00 ± 0.0b a,b,c,d means in the same row with different superscript differ significantly (p<0.05)

Table 2: Antibacterial activities of decoction of medicinal plants.