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activity was observed in 12 plants namely Lawsonia inermis, Eucalyptus sp. Holarrhena antidysenterica, Hemidesmus indicus, C. equistifolia, T. bellerica, T. chebula, Emblica officinalis, Camellia sinensis, S. aromaticum, Plumbago zeylanica and Punica granatum [40]. Antimicrobial activity of Allium sativum on three human pathogenic bacteria had been demonstrated . The extract showed activity against all three bacteria viz. S. aureus, S. typhimurium and Yersinia enterocolitica by disc diffusion method [48]. Petrol, acetone, chloroform and methanol extracts of the leaves and stems of two different varieties of Hypericum were tested by disc diffusion method. Both species Hypericum mysorence and Hypericum patulum showed broad spectrum activity against all six test bacteria [49]. The activity of aqueous and ethyl acetate extracts of the leaves of Piper regnellii was evaluated against Gram positive and Gram negative bacteria. Four compounds viz eupomatenoid–6, eupomatenoid-5, eupomatenoid-3 and conocarpan were isolated. The first two compounds showed very good activity with MIC of <3.12 µg/ml, while last compound showed MIC of 6.25 µg/ml against S. aureus and B. subtilis [50]. Antibacterial activity of 50 plant species of 33 families had been demonstrated which had documented in Iranian traditional medicine. Among the active plants, 32.6% were active against Gram -ve, 62% against Gram +ve and 47.3% against both groups [32]. The bactericidal activity of the whole extract of Eremophila duttonii was checked out by Time kill experiment and demonstrated that it could reduced the bacterial cells to the undetectable level [51]. Plumbago zeylanica extracts (ethyl acetate fraction) also showed the bactericidal activity against Helicobacter pylori. Four fold MIC concentrations of the extracts killed all the population with in the 4 hrs of incubation while the two fold concentration showed the similar effect in 8 hrs [52]. In-vitro inhibitory effect of roselle calyx and protocatechuic acid was found on the growth of methicillin resistant S. aureus. K. pneumoniae, P. aeruginosa and Acinetobacter brumannii. It was observed that both roselle calyx and protocatechuic acid inhibited effectively the growth of all test bacteria [53].Ten traditionally used Nigerian medicinal plants were tested against multidrug resistant S. typhi strains, of which six plants showed MIC and MBC in the range of 9-6 to 14 µg/ml and 40-33 µg/ml respectively against multi resistant S. typhi strains [54]. Recently, the antibacterial activity of medicinal plants had been reviewed against drug resistant bacteria as well as against Candida albicans. Many plants have been identified for characterizing the active principles [16].